Open AccessNew member of the guanosine triphosphatase activating protein family in the human epididymis
Author(s) -
Li Xiangqi,
Liu Qiang,
Liu Shigui,
Zhang Jinsong,
Zhang Yonglian
Publication year - 2008
Publication title -
acta biochimica et biophysica sinica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.771
H-Index - 57
eISSN - 1745-7270
pISSN - 1672-9145
DOI - 10.1111/j.1745-7270.2008.00468.x
Subject(s) - epididymis , triphosphatase , guanosine , adenosine triphosphatase , chemistry , biology , microbiology and biotechnology , biochemistry , atpase , genetics , enzyme , sperm
The effect of the guanosine triphosphatase activating proteins (GAPs) on spermatogenesis has been studied for years, though no GAPs have been explored in epididymis, an essential organ for sperm maturation. In this study, a new GAP member, designated as MacGAP, was cloned in human epididymis. The Mac GAP geneencodesaprotein of 618 amino acids with a putative size of 70 kDa and harbors the conserved RhoGAP domain. The N‐terminal and C‐terminal peptides of MacGAP were expressed and their corresponding antisera were prepared. The antisera against N‐terminal peptide could detect antigen as low as 0.3 ng, and its specificity was also confirmed. However, the antisera against C‐terminal peptide failed to detect its antigen because of its low sensitivity. Immunohistochemistry showed that the MacGAP protein was dependent on epididymis and had a region‐specific expression pattern, with high expression in the epithelial cells’ basal section in the caput region. The results have created a foundation for further interpretation of the biological effects of GAPs in sperm maturation.