Pcdp1 mRNA expression. (A) Northern analysis of Pcdp1 mRNA in brain (br), heart (he), kidney (ki), liver (li) (38), lung (lu), muscle (mu), skin (sk), small intestine (si), spleen (sp), stomach (st), testis (te), and thymus (th). (B) RT-PCR of Pcdp1 in wild-type (WT) and nm1054 (nm) testes specimens. Reactions lacking either reverse transcriptase (-RT) or template (no cDNA) were used as negative controls. β-Actin was used as a loading control. (C to F) Radioactive in situ hybridization analysis of Pcdp1 expression in 8-week-old B6129F1 wild-type testis (C), nm1054 testis (D), wild-type sinus (E), and nm1054 sinus (F). Dusty, black, granular staining indicates Pcdp1 mRNA expression in wild-type spermatocytes and spermatids (C), as well as in wild-type sinus epithelium (E).