TY - JOUR AU - Mulder, Tiara AU - Johnson, Jennifer AU - Gonzalez-Morales, Nicanor TI - The filamins of Drosophila JF - GENOME J2 - GENOME VL - 68 PY - 2025 SP - 1 EP - 11 PG - 11 SN - 0831-2796 DO - 10.1139/gen-2024-0159 UR - https://m2.mtmt.hu/api/publication/35838026 ID - 35838026 LA - English DB - MTMT ER - TY - JOUR AU - Bíró, Péter AU - Novák, Tibor AU - Czvik, Elvira AU - Mihály, József AU - Szikora, Szilárd AU - van de Linde, Sebastian AU - Erdélyi, Miklós TI - Triggered cagedSTORM microscopy JF - BIOMEDICAL OPTICS EXPRESS J2 - BIOMED OPT EXPRESS VL - 15 PY - 2024 IS - 6 SP - 3715 EP - 3726 PG - 12 SN - 2156-7085 DO - 10.1364/BOE.517480 UR - https://m2.mtmt.hu/api/publication/34856915 ID - 34856915 N1 - Funding Agency and Grant Number: Kulturalis Technologiai Miniszterium [TKP2021-NVA-19]; Orszagos Tudomanyos Kutatasi Alapprogramok [FK138894, K132782]; Magyar Tudomanyos Akademia; Nemzeti Kutatasi, Fejlesztesi es Innovacios Alap [UNKP-22-5]; Szegedi Tudomanyegyetem Funding text: Kulturalis Technologiai Miniszterium (TKP2021-NVA-19); Orszagos Tudomanyos Kutatasi Alapprogramok (FK138894, K132782); Magyar Tudomanyos Akademia (Janos Bolyai Research Scholarship); Nemzeti Kutatasi, Fejlesztesi es Innovacios Alap (UNKP-22-5); Szegedi Tudomanyegyetem (Open Access Fund). AB - In standard SMLM methods, the photoswitching of single fluorescent molecules and the data acquisition processes are independent, which leads to the detection of single molecule blinking events on several consecutive frames. This mismatch results in several data points with reduced localization precision, and it also increases the possibilities of overlapping. Here we discuss how the synchronization of the fluorophores’ ON state to the camera exposure time increases the average intensity of the captured point spread functions and hence improves the localization precision. Simulations and theoretical results show that such synchronization leads to fewer localizations with 15% higher sum signal on average, while reducing the probability of overlaps by 10%. LA - English DB - MTMT ER - TY - JOUR AU - Douglas, C.M. AU - Bird, J.E. AU - Kopinke, D. AU - Esser, K.A. TI - An optimized approach to study nanoscale sarcomere structure utilizing super-resolution microscopy with nanobodies JF - PLOS ONE J2 - PLOS ONE VL - 19 PY - 2024 IS - 4 April SN - 1932-6203 DO - 10.1371/journal.pone.0300348 UR - https://m2.mtmt.hu/api/publication/34937889 ID - 34937889 N1 - Department of Physiology and Aging, University of Florida, Gainesville, FL, United States Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL, United States Export Date: 6 June 2024 CODEN: POLNC Correspondence Address: Esser, K.A.; Department of Physiology and Aging, United States; email: kaesser@ufl.edu AB - The sarcomere is the fundamental contractile unit in skeletal muscle, and the regularity of its structure is critical for function. Emerging data demonstrates that nanoscale changes to the regularity of sarcomere structure can affect the overall function of the protein dense ~2μm sarcomere. Further, sarcomere structure is implicated in many clinical conditions of muscle weakness. However, our understanding of how sarcomere structure changes in disease, especially at the nanoscale, has been limited in part due to the inability to robustly detect and measure at sub-sarcomere resolution. We optimized several methodological steps and developed a robust pipeline to analyze sarcomere structure using structured illumination super-resolution microscopy in conjunction with commercially-available and fluorescently-conjugated Variable Heavy-Chain only fragment secondary antibodies (nanobodies), and achieved a significant increase in resolution of z-disc width (353nm vs. 62nm) compared to confocal microscopy. The combination of these methods provides a unique approach to probe sarcomere protein localization at the nanoscale and may prove advantageous for analysis of other cellular structures. Copyright: © 2024 Douglas et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. LA - English DB - MTMT ER - TY - JOUR AU - Farkas, Dávid AU - Szikora, Szilárd AU - Jijumon, A S AU - Polgár, Tamás Ferenc AU - Patai, Roland AU - Szütsné Tóth, Mónika Ágnes AU - Bugyi, Beáta AU - Gajdos, Tamás AU - Bíró, Péter AU - Novák, Tibor AU - Erdélyi, Miklós AU - Mihály, József TI - Peripheral thickening of the sarcomeres and pointed end elongation of the thin filaments are both promoted by SALS and its formin interaction partners JF - PLOS GENETICS J2 - PLOS GENET VL - 20 PY - 2024 IS - 1 PG - 31 SN - 1553-7390 DO - 10.1371/journal.pgen.1011117 UR - https://m2.mtmt.hu/api/publication/34506131 ID - 34506131 AB - During striated muscle development the first periodically repeated units appear in the premyofibrils, consisting of immature sarcomeres that must undergo a substantial growth both in length and width, to reach their final size. Here we report that, beyond its well established role in sarcomere elongation, the Sarcomere length short (SALS) protein is involved in Z-disc formation and peripheral growth of the sarcomeres. Our protein localization data and loss-of-function studies in the Drosophila indirect flight muscle strongly suggest that radial growth of the sarcomeres is initiated at the Z-disc. As to thin filament elongation, we used a powerful nanoscopy approach to reveal that SALS is subject to a major conformational change during sarcomere development, which might be critical to stop pointed end elongation in the adult muscles. In addition, we demonstrate that the roles of SALS in sarcomere elongation and radial growth are both dependent on formin type of actin assembly factors. Unexpectedly, when SALS is present in excess amounts, it promotes the formation of actin aggregates highly resembling the ones described in nemaline myopathy patients. Collectively, these findings helped to shed light on the complex mechanisms of SALS during the coordinated elongation and thickening of the sarcomeres, and resulted in the discovery of a potential nemaline myopathy model, suitable for the identification of genetic and small molecule inhibitors. LA - English DB - MTMT ER - TY - JOUR AU - Fisher, L.A.B. AU - Carriquí-Madroñal, B. AU - Mulder, T. AU - Huelsmann, S. AU - Schöck, F. AU - González-Morales, N. TI - Filamin protects myofibrils from contractile damage through changes in its mechanosensory region JF - PLOS GENETICS J2 - PLOS GENET VL - 20 PY - 2024 IS - 6 June SN - 1553-7390 DO - 10.1371/journal.pgen.1011101 UR - https://m2.mtmt.hu/api/publication/35163084 ID - 35163084 N1 - Department of Biology, McGill University, Montreal, QC, Canada Interfaculty Institute of Cell Biology, Universität Tübingen, Tübingen, Germany Department of Biology, Dalhousie University, Halifax, NS, Canada Export Date: 8 August 2024 Correspondence Address: Schöck, F.; Department of Biology, Canada; email: frieder.schoeck@mcgill.ca Correspondence Address: González-Morales, N.; Department of Biology, Canada; email: nicanor.gonzalez@dal.ca AB - Filamins are mechanosensitive actin crosslinking proteins that organize the actin cytoskeleton in a variety of shapes and tissues. In muscles, filamin crosslinks actin filaments from opposing sarcomeres, the smallest contractile units of muscles. This happens at the Z-disc, the actin-organizing center of sarcomeres. In flies and vertebrates, filamin mutations lead to fragile muscles that appear ruptured, suggesting filamin helps counteract muscle rupturing during muscle contractions by providing elastic support and/or through signaling. An elastic region at the C-terminus of filamin is called the mechanosensitive region and has been proposed to sense and counteract contractile damage. Here we use molecularly defined mutants and microscopy analysis of the Drosophila indirect flight muscles to investigate the molecular details by which filamin provides cohesion to the Z-disc. We made novel filamin mutations affecting the C-terminal region to interrogate the mechanosensitive region and detected three Z-disc phenotypes: dissociation of actin filaments, Z-disc rupture, and Z-disc enlargement. We tested a constitutively closed filamin mutant, which prevents the elastic changes in the mechanosensitive region and results in ruptured Z-discs, and a constitutively open mutant which has the opposite elastic effect on the mechanosensitive region and gives rise to enlarged Z-discs. Finally, we show that muscle contraction is required for Z-disc rupture. We propose that filamin senses myofibril damage by elastic changes in its mechanosensory region, stabilizes the Z-disc, and counteracts contractile damage at the Z-disc. © 2024 Fisher et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. LA - English DB - MTMT ER - TY - JOUR AU - O'Brien, Amanda AU - Hayton, Alastair AU - Cutler, Keith AU - Adler, Andy AU - Shaw, Darren J. AU - Clarke, John AU - Watt, Neil AU - Harkiss, Gordon D. TI - Diagnostic accuracy of the Enferplex Bovine TB antibody test using individual milk samples from cattle JF - PLOS ONE J2 - PLOS ONE VL - 19 PY - 2024 IS - 4 PG - 17 SN - 1932-6203 DO - 10.1371/journal.pone.0301609 UR - https://m2.mtmt.hu/api/publication/34917580 ID - 34917580 LA - English DB - MTMT ER - TY - JOUR AU - González Morales, Nicanor AU - Marescal, Océane AU - Szikora, Szilárd AU - Katzemich, Anja AU - Correia-Mesquita, Tuana AU - Bíró, Péter AU - Erdélyi, Miklós AU - Mihály, József AU - Schöck, Frieder TI - The oxoglutarate dehydrogenase complex is involved in myofibril growth and Z-disc assembly in Drosophila JF - JOURNAL OF CELL SCIENCE J2 - J CELL SCI VL - 136 PY - 2023 IS - 13 PG - 12 SN - 0021-9533 DO - 10.1242/jcs.260717 UR - https://m2.mtmt.hu/api/publication/34043007 ID - 34043007 AB - Myofibrils are long intracellular cables specific to muscles, composed mainly of actin and myosin filaments. The actin and myosin filaments are organized into repeated units called sarcomeres, which form the myofibrils. Muscle contraction is achieved by the simultaneous shortening of sarcomeres, which requires all sarcomeres to be the same size. Muscles have a variety of ways to ensure sarcomere homogeneity. We have previously shown that the controlled oligomerization of Zasp proteins sets the diameter of the myofibril. Here, we looked for Zasp-binding proteins at the Z-disc to identify additional proteins coordinating myofibril growth and assembly. We found that the E1 subunit of the oxoglutarate dehydrogenase complex localizes to both the Z-disc and the mitochondria, and is recruited to the Z-disc by Zasp52. The three subunits of the oxoglutarate dehydrogenase complex are required for myofibril formation. Using super-resolution microscopy, we revealed the overall organization of the complex at the Z-disc. Metabolomics identified an amino acid imbalance affecting protein synthesis as a possible cause of myofibril defects, which is supported by OGDH-dependent localization of ribosomes at the Z-disc. LA - English DB - MTMT ER - TY - JOUR AU - Loreau, V. AU - Rees, R. AU - Chan, E.H. AU - Taxer, W. AU - Gregor, K. AU - Mußil, B. AU - Pitaval, C. AU - Luis, N.M. AU - Mangeol, P. AU - Schnorrer, F. AU - Görlich, D. TI - A nanobody toolbox to investigate localisation and dynamics of Drosophila titins and other key sarcomeric proteins JF - ELIFE J2 - ELIFE VL - 12 PY - 2023 SN - 2050-084X DO - 10.7554/eLife.79343 UR - https://m2.mtmt.hu/api/publication/33742669 ID - 33742669 N1 - Turing Centre for Living Systems, Aix-Marseille University, CNRS, IDBM, Marseille, France Department of Cellular Logistics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany Cited By :1 Export Date: 11 April 2023 Correspondence Address: Schnorrer, F.; Turing Centre for Living Systems, France; email: frank.schnorrer@univ-amu.fr Correspondence Address: Görlich, D.; Department of Cellular Logistics, Germany; email: goerlich@mpinat.mpg.de Chemicals/CAS: kanamycin, 11025-66-4, 61230-38-4, 8063-07-8; Connectin; Single-Domain Antibodies Tradenames: Zeiss LSM880, Carl Zeiss Manufacturers: Carl Zeiss Funding details: 856118, ANR-11-IDEX-0001–02 Funding details: Aix-Marseille Université, AMU Funding details: European Research Council, ERC Funding details: Human Frontier Science Program, HFSP, RGP0052/2018 Funding details: Agence Nationale de la Recherche, ANR Funding details: Max-Planck-Gesellschaft, MPG Funding details: Centre National de la Recherche Scientifique, CNRS Funding details: Fondation Bettencourt Schueller, ANR-10-INBS-04–01, ANR-16-CONV-0001 Funding text 1: We thank Stefan Raunser and Mathias Gautel and all their group members, as well as the Schnorrer and Görlich groups for their stimulating discussions within the StuDySARCOMERE ERC synergy grant. We thank Metin Aksu for help with the Octet measurements. We thank Ulrike Teichmann and her team for alpaca care and immunisations. We are grateful to the IBDM imaging and fly facilities for help with image acquisition, maintenance of the microscopes, and fly food. This work was supported by the Centre National de la Recherche Scientifique (CNRS, FS, CP, NML), the Max Planck Society (D G), Aix-Marseille University (PM), the European Research Council under the European Union’s Horizon 2020 Programme (ERC-2019-SyG 856118 to DG and FS), the excellence initiative Aix-Marseille University A*MIDEX (ANR-11-IDEX-0001–02, FS), the French National Research Agency with ANR-ACHN MUSCLE-FORCES (FS), the Human Frontier Science Program (HFSP, RGP0052/2018, FS), the Bettencourt Schueller Foundation (FS), the France-BioImaging national research infrastructure (ANR-10-INBS-04–01) and by funding from France 2030, the French Government program managed by the French National Research Agency (ANR-16-CONV-0001) and from Excellence Initiative of Aix-Marseille University-A*MIDEX (Turing Center for Living Systems) and LabEx-INFORM (FS and VL). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Funding text 2: We thank Stefan Raunser and Mathias Gautel and all their group members, as well as the Schnorrer and Görlich groups for their stimulating discussions within the StuDySARCOMERE ERC synergy grant. We thank Metin Aksu for help with the Octet measurements. We thank Ulrike Teichmann and her team for alpaca care and immunisations. We are grateful to the IBDM imaging and fly facilities for help with image acquisition, maintenance of the microscopes, and fly food. This work was supported by the Centre National de la Recherche Scientifique (CNRS, FS, CP, NML), the Max Planck Society (D G), Aix-Marseille University (PM), the European Research Council under the European Union’s Horizon 2020 Programme (ERC-2019-SyG 856118 to DG and FS), the excellence initiative Aix-Marseille University A*MIDEX (ANR-11-IDEX-0001–02, FS), the French National Research Agency with ANR-ACHN MUSCLE-FORCES (FS), the Human Frontier Science Program (HFSP, RGP0052/2018, FS), the Bettencourt Schueller Foundation (FS), the France-BioImaging national research infrastructure (ANR-10-INBS-04–01) and by funding from France 2030, the French Government program managed by the French National Research Agency (ANR-16-CONV-0001) and from Excellence Initiative of Aix-Marseille University - A*MIDEX (Turing Center for Living Systems) and LabEx-INFORM (FS and VL). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. AB - Measuring the positions and dynamics of proteins in intact tissues or whole animals is key to understanding protein function. However, to date, this is challenging, as the accessibility of large antibodies to dense tissues is often limited, and fluorescent proteins inserted close to a domain of interest may affect protein function. These complications apply in particular to muscle sarcomeres, arguably one of the most protein-dense assemblies in nature, which complicates studying sarcomere morphogenesis at molecular resolution. Here, we introduce a toolbox of nano-bodies recognising various domains of the two Drosophila titin homologs, Sallimus and Projectin, as well as the key sarcomeric proteins Obscurin, α-Actinin, and Zasp52. We verified the superior labelling qualities of our nanobodies in muscle tissue as compared to antibodies. By applying our toolbox to larval muscles, we found a gigantic Sallimus isoform stretching more than 2 µm to bridge the sarcomeric I-band, while Projectin covers almost the entire myosin filaments in a polar orientation. Transgenic expression of tagged nanobodies confirmed their high affinity-binding without affecting target protein function. Finally, adding a degradation signal to anti-Sallimus nanobodies suggested that it is difficult to fully degrade Sallimus in mature sarcomeres; however, expression of these nano-bodies caused developmental lethality. These results may inspire the generation of similar toolboxes for other large protein complexes in Drosophila or mammals. © Loreau et al. LA - English DB - MTMT ER - TY - JOUR AU - Schueder, Florian AU - Mangeol, Pierre AU - Chan, Eunice HoYee AU - Rees, Renate AU - Schunemann, Juergen AU - Jungmann, Ralf AU - Gorlich, Dirk AU - Schnorrer, Frank TI - Nanobodies combined with DNA-PAINT super-resolution reveal a staggered titin nanoarchitecture in flight muscles JF - ELIFE J2 - ELIFE VL - 12 PY - 2023 PG - 24 SN - 2050-084X DO - 10.7554/eLife.79344 UR - https://m2.mtmt.hu/api/publication/33932206 ID - 33932206 N1 - Faculty of Physics and Center for Nanoscience, Ludwig Maximilian University, Munich, Germany Max Planck Institute of Biochemistry, Martinsried, Germany Aix Marseille University, CNRS, IBDM, Turing Centre for Living Systems, Marseille, France Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany Cited By :2 Export Date: 12 September 2023 Correspondence Address: Jungmann, R.; Faculty of Physics and Center for Nanoscience, Germany; email: jungmann@biochem.mpg.de Correspondence Address: Görlich, D.; Max Planck Institute for Multidisciplinary SciencesGermany; email: goerlich@mpinat.mpg.de Correspondence Address: Schnorrer, F.; Aix Marseille University, France; email: frank.schnorrer@univ-amu.fr AB - Sarcomeres are the force-producing units of all striated muscles. Their nanoarchitecture critically depends on the large titin protein, which in vertebrates spans from the sarcomeric Z-disc to the M-band and hence links actin and myosin filaments stably together. This ensures sarcomeric integrity and determines the length of vertebrate sarcomeres. However, the instructive role of titins for sarcomeric architecture outside of vertebrates is not as well understood. Here, we used a series of nanobodies, the Drosophila titin nanobody toolbox, recognising specific domains of the two Drosophila titin homologs Sallimus and Projectin to determine their precise location in intact flight muscles. By combining nanobodies with DNA-PAINT super-resolution microscopy, we found that, similar to vertebrate titin, Sallimus bridges across the flight muscle I-band, whereas Projectin is located at the beginning of the A-band. Interestingly, the ends of both proteins overlap at the I-band/A-band border, revealing a staggered organisation of the two Drosophila titin homologs. This architecture may help to stably anchor Sallimus at the myosin filament and hence ensure efficient force transduction during flight. LA - English DB - MTMT ER - TY - JOUR AU - Szatmári, Dávid Zoltán AU - Bugyi, Beáta AU - Pintér, Réka AU - Lőrinczy, Dénes TI - Cyclophosphamide treatment modifies the thermal stability of profilin bound monomeric and leiomodin2 bound filamentous actin JF - JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY J2 - J THERM ANAL CALORIM VL - 148 PY - 2023 IS - 3 SP - 837 EP - 844 PG - 8 SN - 1388-6150 DO - 10.1007/s10973-022-11668-y UR - https://m2.mtmt.hu/api/publication/33299326 ID - 33299326 AB - The monomeric (G-actin) and polymer (F-actin) forms of actin play important role in muscle development and contraction, cellular motility, division, and transport processes. Leiomodins 1–3 (Lmod1–3) are crucial for the development of muscle sarcomeres. Unlike tropomodulins that localize only at the pointed ends, the striated muscle specific Lmod2 shows diffuse distribution along the entire length of the thin filaments. The G-actin-binding profilin (Pro) facilitates the nucleotide exchange on monomeric actin and inhibits the polymerization at the barbed end, therefore contributes to the maintenance of the intracellular pool of polymerization competent ATP-G-actin. Cyclophosphamide (CP) is a cytostatic drug that can have potential side effects on muscle thin filaments at the level of actin in myofilaments. Here, we aimed at investigating the influence of CP on actin and its complexes with actin-binding proteins by using differential scanning calorimetry (DSC). We found that upon CP treatment, the denaturation of the Pro-G-actin and Lmod2-F-actin complexes was characterized by an increased enthalpy change. However, after the CP treatment, the melting temperature of F-actin was the same as in the presence of Lmod2, seems like Lmod2 does not have any effect on the structure of the CP alkylated F-actin. In case of Pro bound G-actin the melting temperature did not respond to the CP addition. The intracellular function of Lmod2 in muscle cells can be modified within CP drug treatment. LA - English DB - MTMT ER - TY - JOUR AU - Varga, Dániel AU - Szikora, Szilárd AU - Novák, Tibor AU - Pap, Gergely AU - Lékó, Gábor AU - Mihály, József AU - Erdélyi, Miklós TI - Machine learning framework to segment sarcomeric structures in SMLM data JF - SCIENTIFIC REPORTS J2 - SCI REP VL - 13 PY - 2023 IS - 1 PG - 10 SN - 2045-2322 DO - 10.1038/s41598-023-28539-7 UR - https://m2.mtmt.hu/api/publication/33708203 ID - 33708203 N1 - Funding Agency and Grant Number: University of Szeged Funding text: Open access funding provided by University of Szeged. AB - Object detection is an image analysis task with a wide range of applications, which is difficult to accomplish with traditional programming. Recent breakthroughs in machine learning have made significant progress in this area. However, these algorithms are generally compatible with traditional pixelated images and cannot be directly applied for pointillist datasets generated by single molecule localization microscopy (SMLM) methods. Here, we have improved the averaging method developed for the analysis of SMLM images of sarcomere structures based on a machine learning object detection algorithm. The ordered structure of sarcomeres allows us to determine the location of the proteins more accurately by superimposing SMLM images of identically assembled proteins. However, the area segmentation process required for averaging can be extremely time-consuming and tedious. In this work, we have automated this process. The developed algorithm not only finds the regions of interest, but also classifies the localizations and identifies the true positive ones. For training, we used simulations to generate large amounts of labelled data. After tuning the neural network’s internal parameters, it could find the localizations associated with the structures we were looking for with high accuracy. We validated our results by comparing them with previous manual evaluations. It has also been proven that the simulations can generate data of sufficient quality for training. Our method is suitable for the identification of other types of structures in SMLM data. LA - English DB - MTMT ER - TY - JOUR AU - Zacharchenko, Thomas AU - Dorendorf, Till AU - Locker, Nicolas AU - Van Dijk, Evert AU - Katzemich, Anja AU - Diederichs, Kay AU - Bullard, Belinda AU - Mayans, Olga TI - PK1 from Drosophila obscurin is an inactive pseudokinase with scaffolding properties JF - OPEN BIOLOGY J2 - OPEN BIOL VL - 13 PY - 2023 IS - 4 PG - 13 SN - 2046-2441 DO - 10.1098/rsob.220350 UR - https://m2.mtmt.hu/api/publication/33942654 ID - 33942654 N1 - Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, United Kingdom Department of Biology, University of Konstanz, Konstanz, 78457, Germany Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom Biosynth B.V., Zuidersluisweg 2, Lelystad, 8243 RC, Netherlands Department of Biology, University of York, York, United Kingdom Wellcome Centre for Cell-Matrix Research, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom Department of Biology, McGill University, Montreal, QC H3A 1B1, Canada Export Date: 12 September 2023 Correspondence Address: Mayans, O.; Institute of Integrative Biology, United Kingdom; email: olga.mayans@uni-konstanz.de AB - Obscurins are large filamentous proteins with crucial roles in the assembly, stability and regulation of muscle. Characteristic of these proteins is a tandem of two C-terminal kinase domains, PK1 and PK2, that are separated by a long intrinsically disordered sequence. The significance of this conserved domain arrangement is unknown. Our study of PK1 from Drosophila obscurin shows that this is a pseudokinase with features typical of the CAM-kinase family, but which carries a minimalistic regulatory tail that no longer binds calmodulin or has mechanosensory properties typical of other sarcomeric kinases. PK1 binds ATP with high affinity, but in the absence of magnesium and lacks detectable phosphotransfer activity. It also has a highly diverged active site, strictly conserved across arthropods, that might have evolved to accommodate an unconventional binder. We find that PK1 interacts with PK2, suggesting a functional relation to the latter. These findings lead us to speculate that PK1/PK2 form a pseudokinase/kinase dual system, where PK1 might act as an allosteric regulator of PK2 and where mechanosensing properties, akin to those described for regulatory tails in titin-like kinases, might now reside on the unstructured interkinase segment. We propose that the PK1-interkinase-PK2 region constitutes an integrated functional unit in obscurin proteins. LA - English DB - MTMT ER - TY - JOUR AU - Schöck, F. AU - González-Morales, N. TI - The insect perspective on Z-disc structure and biology JF - JOURNAL OF CELL SCIENCE J2 - J CELL SCI VL - 135 PY - 2022 IS - 20 SN - 0021-9533 DO - 10.1242/jcs.260179 UR - https://m2.mtmt.hu/api/publication/33550868 ID - 33550868 N1 - Export Date: 10 January 2023 CODEN: JNCSA AB - Myofibrils are the intracellular structures formed by actin and myosin filaments. They are paracrystalline contractile cables with unusually well-defined dimensions. The sliding of actin past myosin filaments powers contractions, and the entire system is held in place by a structure called the Z-disc, which anchors the actin filaments. Myosin filaments, in turn, are anchored to another structure called the M-line. Most of the complex architecture of myofibrils can be reduced to studying the Z-disc, and recently, important advances regarding the arrangement and function of Z-discs in insects have been published. On a very small scale, we have detailed protein structure information. At the medium scale, we have cryo-electron microscopy maps, super-resolution microscopy and protein–protein interaction networks, while at the functional scale, phenotypic data are available from precise genetic manipulations. All these data aim to answer how the Z-disc works and how it is assembled. Here, we summarize recent data from insects and explore how it fits into our view of the Z-disc, myofibrils and, ultimately, muscles. © 2022. Published by The Company of Biologists Ltd. LA - English DB - MTMT ER - TY - JOUR AU - Song, Shen AU - Shi, Anteng AU - Lian, Hong AU - Hu, Shengshou AU - Nie, Yu TI - Filamin C in cardiomyopathy: from physiological roles to DNA variants JF - HEART FAILURE REVIEWS J2 - HEART FAIL REV VL - 27 PY - 2022 IS - 4 SP - 1373 EP - 1385 PG - 13 SN - 1382-4147 DO - 10.1007/s10741-021-10172-z UR - https://m2.mtmt.hu/api/publication/32382489 ID - 32382489 N1 - Cited By :2 Export Date: 5 August 2022 CODEN: HFREF AB - Cardiomyopathy affects approximately 1 in 500 adults and is the leading cause of death. Familial cases are common, and mutations in many genes are involved in cardiomyopathy, especially those in genes encoding cytoskeletal, sarcomere, and nuclear envelope proteins. Filamin C is an actin-binding protein encoded by filamin C (FLNC) gene and participates in sarcomere stability maintenance. FLNC was first demonstrated to be a causal gene of myofibrillar myopathy; recently, it has been found that FLNC mutation plays a critical role in the pathogenesis of cardiomyopathy. In this review, we summarized the physiological roles of filamin C in cardiomyocytes and the genetic evidence for links between FLNC mutations and cardiomyopathies. Truncated FLNC is enriched in dilated cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy. Non-truncated FLNC is enriched in hypertrophic cardiomyopathy and restrictive cardiomyopathy. Two major pathomechanisms in FLNC-related cardiomyopathy have been described: protein aggregation resulting from non-truncating mutations and haploinsufficiency triggered by filamin C truncation. Therefore, it is important to understand the cellular biology and molecular regulation of FLNC to design new therapies to treat patients with FLNC-related cardiomyopathy. LA - English DB - MTMT ER - TY - JOUR AU - Sziklai, Dominik AU - Sallai, J. AU - Papp, Zsombor Mátyás AU - Kellermayer, Dalma Lucia AU - Mártonfalvi, Zsolt AU - Pires, R.H. AU - Kellermayer, Miklós TI - Nanosurgical Manipulation of Titin and Its M-Complex JF - NANOMATERIALS J2 - NANOMATERIALS-BASEL VL - 12 PY - 2022 IS - 2 PG - 17 SN - 2079-4991 DO - 10.3390/nano12020178 UR - https://m2.mtmt.hu/api/publication/32587762 ID - 32587762 N1 - Department of Biophysics and Radiation Biology, Semmelweis University, Tűzoltó Str 37-47, Budapest, H1094, Hungary Zentrum für Innovationskompetenz-Humorale Immunreaktionen bei Kardiovaskulären Erkrankungen, University of Greifswald, Greifswald, 17489, Germany Cited By :4 Export Date: 28 February 2024 Correspondence Address: Kellermayer, M.S.Z.; Department of Biophysics and Radiation Biology, Tűzoltó Str 37-47, Hungary; email: kellermayer.miklos@med.semmelweis-univ.hu LA - English DB - MTMT ER - TY - JOUR AU - Szikora, Szilárd AU - Görög, Péter AU - Mihály, József TI - The mechanisms of thin filament assembly and length regulation in muscles JF - INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES J2 - INT J MOL SCI VL - 23 PY - 2022 IS - 10 PG - 25 SN - 1661-6596 DO - 10.3390/ijms23105306 UR - https://m2.mtmt.hu/api/publication/32840276 ID - 32840276 N1 - Funding Agency and Grant Number: Hungarian Science Foundation (OTKA) [K109330, K132782, FK138894]; National Research, Development, and Innovation Office [NKFIH-871-3/2020]; OTKA Postdoctoral Fellowship [PD 128623] Funding text: This work was supported by the Hungarian Science Foundation (OTKA) (K109330 and K132782 to J.M., FK138894 to S.S.); the National Research, Development, and Innovation Office (NKFIH-871-3/2020 to J.M.); and an OTKA Postdoctoral Fellowship (PD 128623 to S.S.). AB - The actin containing tropomyosin and troponin decorated thin filaments form one of the crucial components of the contractile apparatus in muscles. The thin filaments are organized into densely packed lattices interdigitated with myosin-based thick filaments. The crossbridge interactions between these myofilaments drive muscle contraction, and the degree of myofilament overlap is a key factor of contractile force determination. As such, the optimal length of the thin filaments is critical for efficient activity, therefore, this parameter is precisely controlled according to the workload of a given muscle. Thin filament length is thought to be regulated by two major, but only partially understood mechanisms: it is set by (i) factors that mediate the assembly of filaments from monomers and catalyze their elongation, and (ii) by factors that specify their length and uniformity. Mutations affecting these factors can alter the length of thin filaments, and in human cases, many of them are linked to debilitating diseases such as nemaline myopathy and dilated cardiomyopathy. LA - English DB - MTMT ER - TY - JOUR AU - Dhanyasi, Nagaraju AU - VijayRaghavan, K. AU - Shilo, Ben-Zion AU - Schejter, Eyal D. TI - Microtubules provide guidance cues for myofibril and sarcomere assembly and growth JF - DEVELOPMENTAL DYNAMICS J2 - DEV DYNAM VL - 250 PY - 2021 IS - 1 SP - 60 EP - 73 PG - 14 SN - 1058-8388 DO - 10.1002/dvdy.227 UR - https://m2.mtmt.hu/api/publication/31693035 ID - 31693035 N1 - Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel National Centre for Biological Sciences, TIFR, Bangalore, India Cited By :7 Export Date: 16 September 2024 CODEN: DEDYE Correspondence Address: Schejter, E.D.; Department of Molecular Genetics, Israel; email: eyal.schejter@weizmann.ac.il AB - Background Muscle myofibrils and sarcomeres present exceptional examples of highly ordered cytoskeletal filament arrays, whose distinct spatial organization is an essential aspect of muscle cell functionality. We utilized ultra-structural analysis to investigate the assembly of myofibrils and sarcomeres within developing myotubes of the indirect flight musculature ofDrosophila. Results A temporal sequence composed of three major processes was identified: subdivision of the unorganized cytoplasm of nascent, multi-nucleated myotubes into distinct organelle-rich and filament-rich domains; initial organization of the filament-rich domains into myofibrils harboring nascent sarcomeric units; and finally, maturation of the highly-ordered pattern of sarcomeric thick (myosin-based) and thin (microfilament-based) filament arrays in parallel to myofibril radial growth. Significantly, organized microtubule arrays were present throughout these stages and exhibited dynamic changes in their spatial patterns consistent with instructive roles. Genetic manipulations confirm these notions, and imply specific and critical guidance activities of the microtubule-based cytoskeleton, as well as structural interdependence between the myosin- and actin-based filament arrays. Conclusions Our observations highlight a surprisingly significant, behind-the-scenes role for microtubules in establishment of myofibril and sarcomere spatial patterns and size, and provide a detailed account of the interplay between major cytoskeletal elements in generating these essential contractile myogenic units. LA - English DB - MTMT ER - TY - JOUR AU - Kao, S.-Y. AU - Nikonova, E. AU - Chaabane, S. AU - Sabani, A. AU - Martitz, A. AU - Wittner, A. AU - Heemken, J. AU - Straub, T. AU - Spletter, M.L. TI - A candidate rnai screen reveals diverse rna‐binding protein phenotypes in drosophila flight muscle JF - CELLS J2 - CELLS-BASEL VL - 10 PY - 2021 IS - 10 SN - 2073-4409 DO - 10.3390/cells10102505 UR - https://m2.mtmt.hu/api/publication/32533998 ID - 32533998 N1 - Biomedical Center, Department of Physiological Chemistry, Ludwig‐Maximilians‐Universität München, Großhaderner Str. 9, Martinsried‐Planegg, 82152, Germany Department of Biology, University of Wisconsin at Madison, 1117 W. Johnson St., Madison, WI 53706, United States Molecular Nutrition Medicine, Else Kröner‐Fresenius Center, Technical University of Munich, Freising, 85354, Germany Biomedical Center, Bioinformatics Core Facility, Ludwig‐Maximilians‐Universität München, Großhaderner Str. 9, Martinsried‐Planegg, 82152, Germany Export Date: 13 December 2021 Correspondence Address: Spletter, M.L.; Biomedical Center, Großhaderner Str. 9, Germany; email: maria.spletter@bmc.med.lmu.de AB - The proper regulation of RNA processing is critical for muscle development and the fine-tuning of contractile ability among muscle fiber‐types. RNA binding proteins (RBPs) regulate the diverse steps in RNA processing, including alternative splicing, which generates fiber‐type specific isoforms of structural proteins that confer contractile sarcomeres with distinct biomechanical properties. Alternative splicing is disrupted in muscle diseases such as myotonic dystrophy and dilated cardiomyopathy and is altered after intense exercise as well as with aging. It is therefore important to understand splicing and RBP function, but currently, only a small fraction of the hundreds of annotated RBPs expressed in muscle have been characterized. Here, we demonstrate the utility of Drosophila as a genetic model system to investigate basic developmental mechanisms of RBP function in myogenesis. We find that RBPs exhibit dynamic temporal and fiber‐type specific expression patterns in mRNA‐Seq data and display muscle‐specific phenotypes. We performed knockdown with 105 RNAi hairpins targeting 35 RBPs and report associated lethality, flight, myofiber and sarcomere defects, including flight muscle phenotypes for Doa, Rm62, mub, mbl, sbr, and clu. Knockdown phenotypes of spliceosome components, as highlighted by phenotypes for A‐ complex components SF1 and Hrb87F (hnRNPA1), revealed level‐ and temporal‐dependent myofibril defects. We further show that splicing mediated by SF1 and Hrb87F is necessary for Z‐ disc stability and proper myofibril development, and strong knockdown of either gene results in impaired localization of kettin to the Z‐disc. Our results expand the number of RBPs with a described phenotype in muscle and underscore the diversity in myofibril and transcriptomic phenotypes associated with splicing defects. Drosophila is thus a powerful model to gain disease-relevant insight into cellular and molecular phenotypes observed when expression levels of splicing factors, spliceosome components and splicing dynamics are altered. © 2021 by the author. Licensee MDPI, Basel, Switzerland. LA - English DB - MTMT ER - TY - JOUR AU - Luis, N.M. AU - Schnorrer, F. TI - Mechanobiology of muscle and myofibril morphogenesis JF - Cells and Development VL - 168 PY - 2021 PG - 14 SN - 2667-291X DO - 10.1016/j.cdev.2021.203760 UR - https://m2.mtmt.hu/api/publication/33040388 ID - 33040388 N1 - Cited By :1 Export Date: 5 August 2022 AB - Muscles generate forces for animal locomotion. The contractile apparatus of muscles is the sarcomere, a highly regular array of large actin and myosin filaments linked by gigantic titin springs. During muscle development many sarcomeres assemble in series into long periodic myofibrils that mechanically connect the attached skeleton elements. Thus, ATP-driven myosin forces can power movement of the skeleton. Here we review muscle and myofibril morphogenesis, with a particular focus on their mechanobiology. We describe recent progress on the molecular structure of sarcomeres and their mechanical connections to the skeleton. We discuss current models predicting how tension coordinates the assembly of key sarcomeric components to periodic myofibrils that then further mature during development. This requires transcriptional feedback mechanisms that may help to coordinate myofibril assembly and maturation states with the transcriptional program. To fuel the varying energy demands of muscles we also discuss the close mechanical interactions of myofibrils with mitochondria and nuclei to optimally support powerful or enduring muscle fibers. © 2021 The Authors LA - English DB - MTMT ER - TY - JOUR AU - Russell, B. AU - Solís, C. TI - Mechanosignaling pathways alter muscle structure and function by post-translational modification of existing sarcomeric proteins to optimize energy usage JF - JOURNAL OF MUSCLE RESEARCH AND CELL MOTILITY J2 - J MUSCLE RES CELL M VL - 42 PY - 2021 IS - 2 SP - 367 EP - 380 PG - 14 SN - 0142-4319 DO - 10.1007/s10974-021-09596-9 UR - https://m2.mtmt.hu/api/publication/32010705 ID - 32010705 N1 - Export Date: 12 May 2021 CODEN: JMRMD Correspondence Address: Russell, B.; Department of Physiology and Biophysics, United States; email: russell@uic.edu AB - A transduced mechanical signal arriving at its destination in muscle alters sarcomeric structure and function. A major question addressed is how muscle mass and tension generation are optimized to match actual performance demands so that little energy is wasted. Three cases for improved energy efficiency are examined: the troponin complex for tuning force production, control of the myosin heads in a resting state, and the Z-disc proteins for sarcomere assembly. On arrival, the regulation of protein complexes is often controlled by post-translational modification (PTM), of which the most common are phosphorylation by kinases, deacetylation by histone deacetylases and ubiquitination by E3 ligases. Another branch of signals acts not through peptide covalent bonding but via ligand interactions (e.g. Ca2+ and phosphoinositide binding). The myosin head and the regulation of its binding to actin by the troponin complex is the best and earliest example of signal destinations that modify myofibrillar contractility. PTMs in the troponin complex regulate both the efficiency of the contractile function to match physiologic demand for work, and muscle mass via protein degradation. The regulation of sarcomere assembly by integration of incoming signaling pathways causing the same PTMs or ligand binding are discussed in response to mechanical loading and unloading by the Z-disc proteins CapZ, α-actinin, telethonin, titin N-termini, and others. Many human mutations that lead to cardiomyopathy and heart disease occur in the proteins discussed above, which often occur at their PTM or ligand binding sites. © 2021, The Author(s), under exclusive licence to Springer Nature Switzerland AG part of Springer Nature. LA - English DB - MTMT ER - TY - JOUR AU - Szikora, Szilárd AU - Görög, Péter AU - Kozma, Csaba AU - Mihály, József TI - Drosophila models rediscovered with super-resolution microscopy JF - CELLS J2 - CELLS-BASEL VL - 10 PY - 2021 IS - 8 PG - 22 SN - 2073-4409 DO - 10.3390/cells10081924 UR - https://m2.mtmt.hu/api/publication/32153073 ID - 32153073 N1 - Funding Agency and Grant Number: Szeged Scientists Academy under the Hungarian Ministry of Innovation and Technology [FEIF/433-4/2020-ITM_SZERZ]; Hungarian Science Foundation (OTKA)Orszagos Tudomanyos Kutatasi Alapprogramok (OTKA) [K109330, K132782, PD 128623]; National Research, Development and Innovation OfficeNational Research, Development & Innovation Office (NRDIO) - Hungary [GINOP-2.3.2-15-2016-00001, GINOP-2.3.2-15-2016-00032, GINOP-2.3.2-15-2016-00036] Funding text: This work was conducted with the support of the Szeged Scientists Academy under the sponsorship of the Hungarian Ministry of Innovation and Technology (FEIF/433-4/2020-ITM_SZERZ). This work was also supported by the Hungarian Science Foundation (OTKA) (K109330 and K132782 to J.M.), the National Research, Development and Innovation Office (GINOP-2.3.2-15-2016-00001, GINOP-2.3.2-15-2016-00032 and GINOP-2.3.2-15-2016-00036 to J.M.) and an OTKA Postdoctoral Fellowship (PD 128623, to S.S.). AB - With the advent of super-resolution microscopy, we gained a powerful toolbox to bridge the gap between the cellular- and molecular-level analysis of living organisms. Although nanoscopy is broadly applicable, classical model organisms, such as fruit flies, worms and mice, remained the leading subjects because combining the strength of sophisticated genetics, biochemistry and electrophysiology with the unparalleled resolution provided by super-resolution imaging appears as one of the most efficient approaches to understanding the basic cell biological questions and the molecular complexity of life. Here, we summarize the major nanoscopic techniques and illustrate how these approaches were used in Drosophila model systems to revisit a series of well-known cell biological phenomena. These investigations clearly demonstrate that instead of simply achieving an improvement in image quality, nanoscopy goes far beyond with its immense potential to discover novel structural and mechanistic aspects. With the examples of synaptic active zones, centrosomes and sarcomeres, we will explain the instrumental role of super-resolution imaging pioneered in Drosophila in understanding fundamental subcellular constituents. LA - English DB - MTMT ER - TY - JOUR AU - Gajdos, Tamás AU - Hopp, Béla AU - Erdélyi, Miklós TI - Hot-Band Anti-Stokes Fluorescence Properties of Alexa Fluor 568 JF - JOURNAL OF FLUORESCENCE J2 - J FLUORESC VL - 30 PY - 2020 IS - 3 SP - 437 EP - 443 PG - 7 SN - 1053-0509 DO - 10.1007/s10895-020-02496-0 UR - https://m2.mtmt.hu/api/publication/31202130 ID - 31202130 N1 - Export Date: 4 May 2020 CODEN: JOFLE Correspondence Address: Erdélyi, M.; Department of Optics and Quantum Electronics, University of Szeged, Dóm tér 9., Hungary; email: erdelyi@titan.physx.u-szeged.hu Funding details: EFOP-3.6.1-16-2016-00008 Funding text 1: This work was supported by the Hungarian Brain Research Program (2017-1.2.1-NKP-2017-00002); the GINOP-2.3.2-15-2016-00036; the EU-funded Hungarian Grant EFOP-3.6.1-16-2016-00008. We thank Gábor Laczkó for a fruitful discussion. We would like to acknowledge József Mihály and Szilárd Szikora for providing the drosophila myofibril sample. Open access funding provided by University of Szeged (SZTE). LA - English DB - MTMT ER - TY - JOUR AU - González-Morales, Nicanor AU - Schöck, Frieder TI - Commentary: Nanoscopy reveals the layered organization of the sarcomeric H-zone and I-band complexes JF - FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY J2 - FRONT CELL DEV BIOL VL - 8 PY - 2020 SN - 2296-634X DO - 10.3389/fcell.2020.00074 UR - https://m2.mtmt.hu/api/publication/31321157 ID - 31321157 N1 - Cited By :1 Export Date: 5 August 2022 LA - English DB - MTMT ER - TY - JOUR AU - Islam, Moydul AU - Diwan, Abhinav AU - Mani, Kartik TI - Come Together: Protein Assemblies, Aggregates and the Sarcostat at the Heart of Cardiac Myocyte Homeostasis JF - FRONTIERS IN PHYSIOLOGY J2 - FRONT PHYSIOL VL - 11 PY - 2020 PG - 18 SN - 1664-042X DO - 10.3389/fphys.2020.00586 UR - https://m2.mtmt.hu/api/publication/31545822 ID - 31545822 N1 - Cited By :7 Export Date: 5 August 2022 AB - Homeostasis in vertebrate systems is contingent on normal cardiac function. This, in turn, depends on intricate protein-based cellular machinery, both for contractile function, as well as, durability of cardiac myocytes. The cardiac small heat shock protein (csHsp) chaperone system, highlighted by alpha B-crystallin (CRYAB), a small heat shock protein (sHsp) that forms similar to 3-5% of total cardiac mass, plays critical roles in maintaining proteostatic function via formation of self-assembled multimeric chaperones. In this work, we review these ancient proteins, from the evolutionarily preserved role of homologs in protists, fungi and invertebrate systems, as well as, the role of sHsps and chaperones in maintaining cardiac myocyte structure and function. We propose the concept of the "sarcostat" as a protein quality control mechanism in the sarcomere. The roles of the proteasomal and lysosomal proteostatic network, as well as, the roles of the aggresome, self-assembling protein complexes and protein aggregation are discussed in the context of cardiac myocyte homeostasis. Finally, we will review the potential for targeting the csHsp system as a novel therapeutic approach to prevent and treat cardiomyopathy and heart failure. LA - English DB - MTMT ER - TY - JOUR AU - Marescal, Oceane AU - Schock, Frieder AU - Gonzalez-Morales, Nicanor TI - Bimolecular Fluorescence Complementation (BiFC) for Studying Sarcomeric Protein Interactions in Drosophila JF - BIO-PROTOCOL J2 - BIO-PROTOCOL VL - 10 PY - 2020 IS - 7 PG - 15 SN - 2331-8325 DO - 10.21769/BioProtoc.3569 UR - https://m2.mtmt.hu/api/publication/31693034 ID - 31693034 N1 - Cited By :2 Export Date: 16 September 2024 Correspondence Address: González-Morales, N.; Biology, Canada; email: nicanor.gonzalez-morales@mail.mcgill.ca AB - Protein-protein interactions in Drosophila myofibrils are essential for their function and formation. Bimolecular Fluorescence Complementation (BiFC) is an effective method for studying protein interactions and localization. BiFC relies on the reconstitution of a monomeric fluorescent protein from two half-fragments when in proximity. Two proteins tagged with the different half-fragments emit a fluorescent signal when they are in physical contact, thus revealing a protein interaction and its spatial distribution. Because myofibrils are large networks of interconnected proteins, BIFC is an ideal method to study protein-protein interactions in myofibrils. Here we present a protocol for generating transgenic flies compatible with BiFC and a method for analyzing protein-protein interactions based on the fluorescent BiFC signal in myofibrils. Our protocol is applicable to the majority of Drosophila proteins and with few modifications may be used to study any tissue. LA - English DB - MTMT ER - TY - JOUR AU - Nikonova, E. AU - Kao, S.-Y. AU - Spletter, M.L. TI - Contributions of alternative splicing to muscle type development and function JF - SEMINARS IN CELL & DEVELOPMENTAL BIOLOGY J2 - SEMIN CELL DEV BIOL VL - 104 PY - 2020 SP - 65 EP - 80 PG - 16 SN - 1084-9521 DO - 10.1016/j.semcdb.2020.02.003 UR - https://m2.mtmt.hu/api/publication/31202572 ID - 31202572 N1 - Biomedical Center, Department of Physiological Chemistry, Ludwig-Maximilians-Universität München, Großhaderner Str. 9, Martinsried-Planegg, 82152, Germany Center for Integrated Protein Science Munich (CIPSM) at the Department of Chemistry, Ludwig-Maximilians-Universität München, Munich, Germany Export Date: 2 March 2020 CODEN: SCDBF Correspondence Address: Spletter, M.L.; Biomedical Center, Department of Physiological Chemistry, Ludwig-Maximilians-Universität München, Großhaderner Str. 9, Germany; email: maria.spletter@bmc.med.lmu.de AB - Animals possess a wide variety of muscle types that support different kinds of movements. Different muscles have distinct locations, morphologies and contractile properties, raising the question of how muscle diversity is generated during development. Normal aging processes and muscle disorders differentially affect particular muscle types, thus understanding how muscles normally develop and are maintained provides insight into alterations in disease and senescence. As muscle structure and basic developmental mechanisms are highly conserved, many important insights into disease mechanisms in humans as well as into basic principles of muscle development have come from model organisms such as Drosophila, zebrafish and mouse. While transcriptional regulation has been characterized to play an important role in myogenesis, there is a growing recognition of the contributions of alternative splicing to myogenesis and the refinement of muscle function. Here we review our current understanding of muscle type specific alternative splicing, using examples of isoforms with distinct functions from both vertebrates and Drosophila. Future exploration of the vast potential of alternative splicing to fine-tune muscle development and function will likely uncover novel mechanisms of isoform-specific regulation and a more holistic understanding of muscle development, disease and aging. © 2020 The Authors LA - English DB - MTMT ER - TY - JOUR AU - Szikora, Szilárd AU - Novák, Tibor AU - Gajdos, Tamás AU - Erdélyi, Miklós AU - Mihály, József TI - Superresolution Microscopy of Drosophila Indirect Flight Muscle Sarcomeres JF - BIO-PROTOCOL J2 - BIO-PROTOCOL VL - 10 PY - 2020 IS - 12 PG - 16 SN - 2331-8325 DO - 10.21769/BioProtoc.3654 UR - https://m2.mtmt.hu/api/publication/31661623 ID - 31661623 N1 - Institute of Genetics, Biological Research Centre, Szeged, Hungary Department of Optics and Quantum Electronics, University of Szeged, Szeged, Hungary Cited By :4 Export Date: 16 September 2024 Correspondence Address: Szikora, S.; Institute of Genetics, Hungary; email: szilardszikora@gmail.com Correspondence Address: Mihály, J.; Institute of Genetics, Hungary; email: mihaly.jozsef@brc.hu AB - Sarcomeres are extremely highly ordered macromolecular assemblies where proper structural organization is an absolute prerequisite to the functionality of these contractile units. Despite the wealth of information collected, the exact spatial arrangement of many of the H-zone and Z-disk proteins remained unknown. Recently, we developed a powerful nanoscopic approach to localize the sarcomeric protein components with a resolution well below the diffraction limit. The ease of sample preparation and the near crystalline structure of the Drosophila flight muscle sarcomeres make them ideally suitable for single molecule localization microscopy and structure averaging. Our approach allowed us to determine the position of dozens of H-zone and Z-disk proteins with a quasi-molecular, similar to 5-10 nm localization precision. The protocol described below provides an easy and reproducible method to prepare individual myofibrils for dSTORM imaging. In addition, it includes an in-depth description of a custom made and freely available software toolbox to process and quantitatively analyze the raw localization data. LA - English DB - MTMT ER -