<p>(A) Relative abundance of EGFP in testes of Wildtype, <i>DAZL</i>-deficient and <i>GCS-EGFP</i> rats. <i>Left</i>: Data expressed as the equivalents of recombinant, histidine-tagged EGFP (rEGFP)/testis (+/−SEM, n = 3 testes/rat strain) as determined by fluorometry of testis extracts at 24 days of age. <i>Right</i>: Bright field (top) and green fluorescence (bottom) images of testes dissected from <i>GCS-EGFP</i>, wildtype (WT) and <i>DAZL</i>-deficient (Dazl-Def) rats at 24 days of age. Scale bar = 1 cm. (B) Spermatogenesis colony forming assays using <i>DAZL</i>-deficient rats as recipients. <i>Left</i>: Numbers of spermatogenic colonies formed/testis by donor <i>GCS-EGFP</i> rat spermatogonia in Wildtype (10.25+/−0.68 colonies/testis, +/−SEM, n = 8 testes) and <i>DAZL</i>-Deficient rats (30.69+/−0.62 colonies/testes, +/−SEM, n = 8 testes) at 30 days following transplantation; p<0.0001, unpaired two-tailed students t-test. Donor spermatogonia were transplanted at passages 15 and 17 (i.e. culture days 182 and 204) at 2000 <i>GCS-EGFP</i><sup>+</sup> cells/testis. <i>Right</i>: Images of individual colonies of spermatogenesis in Wildtype and <i>DAZL</i>-deficient recipient rats that were generated by the donor <i>GCS-EGFP</i> spermatogonia (green fluorescence is from donor cells). Images are representative of colonies scored and plotted in the <i>Left</i> panel. Scale bar = 100 µm.</p
