Figure 7

The X chromosome is transcriptionally silenced in spermatogenesis as a result of Meiotic Sex Chromosome Inactivation. (A) The average expression of X-linked genes decreases after 12dpp, and eventually drops by a factor of ~3 in adult testes. (B), (C) Heatmaps of X-linked genes. Only genes selected for temporal clustering are shown (B). The drop in gene expression, relative to genome-wide expression, is evident starting at around 16dpp, the pachytene stage. In the adult testes, at 38dpp, many genes that have not been active during the earlier stages of the first wave of spermatogenesis are turned on. This is also evident from the deconvolution calculations (C).