Figure 2. Expression levels of 39 spermatogenic cell-specific intronless genes are increased in later stages of spermatogenesis.

Semiquantitative RT-PCR was carried out using total RNA isolated from D7, D14, D21, and D35 testes. The number of PCR cycles increases from left to right in each panel, as described in Table S2. The β-actin band represents equal expression levels for each stage. The absence of genomic DNA in RNA samples is shown in Figure S2.