New member of the guanosine triphosphatase activating protein family in the human epididymis.
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 MacGAP gene encodes a protein 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.
College of Life Science, Sichuan University, Chengdu 610064, China.
Xiangqi
X
Li
Qiang
Q
Liu
Shigui
S
Liu
Jinsong
J
Zhang
Yonglian
Y
Zhang
D000328:Adult; D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D017124:Conserved Sequence; D030501:Epididymal Secretory Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004822:Epididymis / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism; D020690:GTPase-Activating Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008969:Molecular Sequence Data; D008970:Molecular Weight; D017434:Protein Structure, Tertiary / Q000235:genetics; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D012680:Sensitivity and Specificity
C542464:ARHGAP18 protein, human; D030501:Epididymal Secretory Proteins; D020690:GTPase-Activating Proteins; D011994:Recombinant Proteins