Figure 2.

Expression during spermatogenesis of autosomal germ-cell-specific genes initiating expression in spermatocytes. Relative levels of transcripts were assessed in specific spermatogenic cell preparations as described for Figure 1. Actb serves as a positive control for ubiquitous expression and Prm1 as a control for significant expression initiated in round spermatids. Relative transcript levels for 20 germ-cell-specific genes that initiate significant levels of expression at the onset of meiosis in primary spermatocytes, plus one other germ-cell-specific gene (Prm1) that initiates low-level expression in spermatocytes and higher expression in round spermatids, are shown below these controls. All these genes are autosomal. Primer sequences and PCR conditions have been deposited in GenBank under accession numbers as described in Materials and Methods.