FIG. 4.

Western blot analysis of BER proteins in nuclear extracts prepared from enriched populations of primitive type A spermatogonia (PA), type A spermatogonia (A), type B spermatogonia (B), pachytene spermatocytes (P), and round spermatids (R). Bands corresponding to DNA ligase I (130 kDa), DNA ligase III (93 kDa), Xrcc-1 (69 kDa), β-pol (39 kDa), and Ape/Ref-1 (37 kDa) proteins were visualized. Triplicate assays for each of three independent nuclear extract preparations were performed. Some variation between replicates was noted. A summary of all data is shown in Table 1. Molecular mass protein standards and purified DNA ligases I and III, β-pol, and Ape/Ref-1 (lane STD) are shown for comparison.