Systematic study of stress-inducible protein 1 (Stip1) in male reproductive system and its expression during stress response

• Stip1 was expressed in various human tissues, including the testis and epididymis.
• Stip1 showed a developmentally-regulated manner in rat testis and epididymis.
• Stip1 was up-regulated after heat shock treatment in rat testis and epididymis.
• Under oxidative stress, Stip1 was down-regulated in rat testis.

Stress-inducible protein 1 (Stip1) is one of the well-studied co-chaperones, although limited researches have been conducted in testis and epididymis. Here we found that Stip1 was ubiquitously expressed in various human tissues, including the testis and epididymis. In human testis and epididymis, Stip1 was localized in the cytoplasm of diverse cell types. Stip1 showed a developmentally-regulated manner and it was up-regulated after heat shock in rat testis and epididymis. However, the expression of Stip1 was significantly down-regulated in the testis, with tremendous histomorphological changes under oxidative stress. This study will lay the foundation for revealing the mechanism of Stip1 in the male reproductive system.