Abstract: Objective To study the space-specific expression and nucleocytoplasmic shuttling of HSD1 in different spermatogenic cells. Methods Mouse spermatogenic cells were isolated and endogenous positioning of HSD1 was observed by immunofluorescence assay. pEGFP-C1-HSD1 expression plasmid was constructed and transfected into CHO cells. Confocal and electron microscopy were used to observe the positioning and nucleocytoplasmic shuttling of HSD1 in cells. Results HSD1 was expressed in the cytoplasm of primary spermatocytes and round spermatids; while it is mainly expressed in the acrosome and tail of mature sperms. There were three distribution forms of HSD1 protein in CHO cells: the nucleus type, the cytoplasm type and the nucleocytoplasmic type. Further study found that distribution of HSD1 was dynamic, and it existed nucleocytoplasmic shuttling in CHO cells. Conclusion HSD1 protein was space-specifically expressed in spermatogenic cells, and had the ability of nucleocytoplasmic shuttling.

Key words: HSD1, spermatogenesis, immunofluorescence, nucleocytoplasmic shuttling