Sperm-associated antigen 11B explained

Sperm-associated antigen 11B is a protein that in humans is encoded by the SPAG11B gene.^{[1] [2] [3]}

Function

This gene encodes several androgen-dependent, epididymis-specific secretory proteins. The specific functions of these proteins have not been determined, but they are thought to be involved in sperm maturation. Some of the isoforms contain regions of similarity to beta-defensins, a family of antimicrobial peptides. The gene is located on chromosome 8p23 near the defensin gene cluster. Alternative splicing of this gene results in seven transcript variants encoding different isoforms. Two different N-terminal and five different C-terminal protein sequences are encoded by the splice variants. Two additional variants have been described, but their full length sequences have not been determined.

Further reading

• Krull N, Ivell R, Osterhoff C, Kirchhoff C . Region-specific variation of gene expression in the human epididymis as revealed by in situ hybridization with tissue-specific cDNAs . Molecular Reproduction and Development . 34 . 1 . 16–24 . January 1993 . 8418812 . 10.1002/mrd.1080340104 . 24008790 .
• Hamil KG, Sivashanmugam P, Richardson RT, Grossman G, Ruben SM, Mohler JL, Petrusz P, O'Rand MG, French FS, Hall SH . HE2beta and HE2gamma, new members of an epididymis-specific family of androgen-regulated proteins in the human . Endocrinology . 141 . 3 . 1245–53 . March 2000 . 10698202 . 10.1210/endo.141.3.7389 . free .
• Fröhlich O, Po C, Murphy T, Young LG . Multiple promoter and splicing mRNA variants of the epididymis-specific gene EP2 . Journal of Andrology . 21 . 3 . 421–30 . 2000 . 10.1002/j.1939-4640.2000.tb03397.x . 10819450 . 32923465 .
• Fröhlich O, Po C, Young LG . Organization of the human gene encoding the epididymis-specific EP2 protein variants and its relationship to defensin genes . Biology of Reproduction . 64 . 4 . 1072–9 . April 2001 . 11259252 . 10.1095/biolreprod64.4.1072 . free .
• von Horsten HH, Derr P, Kirchhoff C . Novel antimicrobial peptide of human epididymal duct origin . Biology of Reproduction . 67 . 3 . 804–13 . September 2002 . 12193388 . 10.1095/biolreprod.102.004564 . free .
• Légaré C, Verville N, Sullivan R . Vasectomy influences expression of HE1 but not HE2 and HE5 genes in human epididymis . Journal of Andrology . 25 . 1 . 30–43 . 2004 . 14662784 . 10.1002/j.1939-4640.2004.tb02756.x. free .
• Avellar MC, Honda L, Hamil KG, Yenugu S, Grossman G, Petrusz P, French FS, Hall SH . Differential expression and antibacterial activity of epididymis protein 2 isoforms in the male reproductive tract of human and rhesus monkey (Macaca mulatta) . Biology of Reproduction . 71 . 5 . 1453–60 . November 2004 . 15229135 . 10.1095/biolreprod.104.031740 . free .

Notes and References

1. Osterhoff C, Kirchhoff C, Krull N, Ivell R . Molecular cloning and characterization of a novel human sperm antigen (HE2) specifically expressed in the proximal epididymis . Biology of Reproduction . 50 . 3 . 516–25 . March 1994 . 8167223 . 10.1095/biolreprod50.3.516 .
2. Kirchhoff C, Osterhoff C, Habben I, Ivell R, Kirchloff C . Cloning and analysis of mRNAs expressed specifically in the human epididymis . International Journal of Andrology . 13 . 2 . 155–67 . April 1990 . 1693137 . 10.1111/j.1365-2605.1990.tb00972.x . free .
3. Web site: Entrez Gene: SPAG11 sperm associated antigen 11.