Microtubule nucleation in eukaryotes is primarily promoted by gamma-tubulin and the
evolutionary conserved protein complex, gamma-Tubulin Ring Complex (gamma-TuRC). gamma-TuRC
is part of the centrosome and basal body, which are the best-known microtubule-organizing
centers. Centrosomes undergo intensive and dynamic changes during spermatogenesis,
as they turn into basal bodies, a prerequisite for axoneme formation during spermatogenesis.
Here we describe the existence of a novel, tissue-specific gamma-TuRC in Drosophila.
We characterize three genes encoding testis-specific components of gamma-TuRC (t-gamma-TuRC)
and find that presence of t-gamma-TuRC is essential to male fertility. We show the
diverse subcellular distribution of the t-gamma-TuRC proteins during post-meiotic
development, at first at the centriole adjunct and then also on the anterior tip of
the nucleus, and finally, they appear in the tail region, close to the mitochondria.
We also prove the physical interactions between the t-gamma-TuRC members, gamma-tubulin
and Mozart1. Our results further indicate heterogeneity in gamma-TuRC composition
during spermatogenesis and suggest that the different post-meiotic microtubule organizing
centers are orchestrated by testis-specific gene products, including t-gamma-TuRC.
