Expression pattern of mitochondrial capsule selenoprotein mRNA in the hamster testis

Mitochondrial capsule selenoprotein (MCS) has been known as a structural protein of the mitochondrial sheath in spermatozoa. In the present study, to determine the expression pattern of MCS mRNA in the hamster testis, northern blot and in situ hybridization analyses using digoxigenin-labeled riboprobes for the hamster MCS were performed in the testes of 10-week-old golden hamsters. According to the northern blot analysis, hamster MCS was detected as a single transcript of about 1 kb in the testis. During spermatogenesis, the hamster MCS mRNA first appeared in step 6 spermatids, gradually increased in round spermatids during spermiogenesis, reached a peak in step 8 spermatids, and persisted a high level until step 13 spermatids. After step 14, the signal began to show a progressive decline in the spermatids and was weakly detected in the tails of step 17 spermatids. However, the signal was not observed in spermatogonia, spermatocytes, Sertoli cells, peritubular myoid cells, and interstitial cells. These findings indicate that hamster MCS is mainly related to the spermiogenesis during spermatogenesis.