Figures & data
Figure 1. Scheme of spermatogenesis in mouse and Drosophila. Left: Germ granules in mouse gonocytes (IMC or pi-bodies, piP-bodiesCitation13,Citation14), spermatogonia, early sprematocytes (IMC), late spermatocytes (IMC, CB precursors) and haploid round spermatids (CB) are depicted. Adapted from ref. Citation2. CB formation coincides with periods of active transcription (arrows) and emerging of abundant pachytene piRNAs. In elongating spermatids the CBs gradually degenerates. Right: Two types of germ granules are found in the Drosophila male germline. There are a lot of small nuage granules, that appear early in germline stem cells, and significantly larger structures, the piNG-bodies. The piNG-bodies form in primary spermatocytes and disappear before meiotic divisions. Arrow indicates massive transcription during spermatocyte growth and maturation. No germ granules are found in round spermatids, where transcription program dramatically ceases.
