Expression Pattern of the Mitochondrial Capsule Selenoprotein mRNA in the Mouse Testis after Puberty; in situ Hybridization Study

Abstract

Mitochondrial capsule selenoprotein (MCS) has been known as a structural protein of the mitochondrial sheath in spermatozoa. In this study, to determine the expression pattern of MCS mRNA in the mouse testis after puberty, in situ hybridization using digoxigenin-labeled RNA probes for MCS was performed in the testes of 8- and 20-week-old ICR mice. In the testes of both ages, MCS mRNA first appeared in step 3 round spermatids, gradually increased during early spermiogenesis, and persisted a high level until step 14 spermatids. After the step 14 spermatids, the signal began to decline and was weakly detected in steps 15-16 spermatids. On the other hand, compared with that in the testes of 8-week-old mice, MCS mRNA level in the testes of 20-week-old mice increased over 2-fold at stages VI-III, while it slightly increased at stages IV-V. These findings suggest that MCS gene transcription may be up-regulated after puberty in the mouse testis.