Human RING finger protein ZNF645 is a novel testis-specific E3 ubiquitin ligase.
A large number of testis-specific genes are involved in the complex process of mammalian spermatogenesis. Identification of these genes and their roles is important for understanding the mechanisms underlying spermatogenesis. Here we report on a novel human RING finger protein, ZNF645, which contains a C3HC4 RING finger domain, a C2H2 zinc-finger domain, and a proline-rich region, indicating that it has a structure similar to that of the c-Cbl-like protein Hakai. ZNF645 was exclusively expressed in normal human testicular tissue. Immunohistochemical analysis confirmed that ZNF645 protein was present in spermatocytes, round and elongated spermatids, and Leydig cells. Immunofluorescence staining of mature sperms further showed that the ZNF645 protein was localized over the postacrosomal perinuclear theca region and the entire length of sperm tail. An in vitro ubiquitination assay indicated that the RING finger domain of the ZNF645 protein had E3 ubiquitin ligase activity. Therefore, we suggest that ZNF645 might act as an E3 ubiquitin-protein ligase and play a role in human sperm production and quality control.
Liu
Yun-Qiang
YQ
Department of Medical Genetics, State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China.
Bai
Gang
G
Zhang
Hao
H
Su
Dan
D
Tao
Da-Chang
DC
Yang
Yuan
Y
Ma
Yong-Xin
YX
Zhang
Si-Zhong
SZ
D000595:Amino Acid Sequence; D015870:Gene Expression; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D054829:RING Finger Domains; D013090:Spermatocytes / Q000737:chemistry*; D013091:Spermatogenesis / Q000235:genetics*; D013737:Testis / Q000737:chemistry*; D015534:Trans-Activators / Q000096:biosynthesis / Q000235:genetics*; D014157:Transcription Factors / Q000096:biosynthesis / Q000235:genetics*; D044767:Ubiquitin-Protein Ligases / Q000096:biosynthesis / Q000235:genetics*; D054875:Ubiquitination
C552601:CBLL2 protein, human; D015534:Trans-Activators; D014157:Transcription Factors; C573234:ZNF644 protein, human; D044767:Ubiquitin-Protein Ligases