title: Sialylation Facilitates the Maturation of Mammalian Sperm and Affects Its Survival in Female Uterus.
abstract: Establishment of adequate levels of sialylation is crucial for sperm survival and function after insemination; however, the mechanism for the addition of the sperm sialome has not been identified. Here, we report evidence for several different mechanisms that contribute to the establishment of the mature sperm sialome. Directly quantifying the source of the nucleotide sugar CMP-beta-N-acetylneuraminic acid in epididymal fluid indicates that transsialylation occurs in the upper epididymis. Western blots for the low-molecular-mass sialoglycoprotein (around 20-50 kDa) in C57BL/6 mice epididymal fluid reflect that additional sialome could be obtained by glycosylphosphatidylinositol-anchored sialoglycopeptide incorporation during epididymal transit in the caput of the epididymis. Additionally, we found that in Cmah (CMP-N-acetylneuraminic acid hydroxylase)-/- transgenic mice, epididymal sperm obtained sialylated-CD52 from seminal vesicle fluid (SVF). Finally, we used Gfp (green fluorescent protein)+/+ mouse sperm to test the role of sialylation on sperm for protection from female leukocyte attack. There is very low phagocytosis of the epididymal sperm when compared to that of sperm coincubated with SVF. Treating sperm with Arthrobacter ureafaciens sialidase (AUS) increased phagocytosis even further. Our results highlight the different mechanisms of increasing sialylation, which lead to the formation of the mature sperm sialome, as well as reveal the sialome's function in sperm survival within the female genital tract.
authors.affiliation: Department of Pediatric Urology, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Xue
authors.initials: X
authors.lastname: Ma
authors.affiliation: Sichuan University - The Chinese University of Hong Kong Joint Laboratory for Reproductive Medicine, Key Laboratory of Obstetric, Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Pan
authors.affiliation: Sichuan University - The Chinese University of Hong Kong Joint Laboratory for Reproductive Medicine, Key Laboratory of Obstetric, Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Feng
authors.affiliation: Shanghai Key Laboratory of Reproductive Medicine, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Biswa P
authors.initials: BP
authors.lastname: Choudhury
authors.affiliation: West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, Sichuan, China m_qianhong@hotmail.com.
authors.forename: Qianhong
authors.initials: Q
authors.lastname: Ma
authors.affiliation: Glycobiology Research and Training Center and Departments of Cellular, University of California, San Diego, La Jolla, California pgagneux@gmail.com.
authors.forename: Pascal
authors.initials: P
authors.lastname: Gagneux
authors.affiliation: Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University, Chengdu, China West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, Sichuan, China Glycobiology Research and Training Center and Departments of Cellular, University of California, San Diego, La Jolla, California mafangmed@126.com.
authors.forename: Fang
authors.initials: F
authors.lastname: Ma
mesh_terms: D000818:Animals; D005260:Female; D008297:Male; D008810:Mice, Inbred C57BL; D019158:N-Acetylneuraminic Acid / Q000378:metabolism*; D013079:Sperm Maturation; D013094:Spermatozoa / Q000502:physiology*; D014599:Uterus / Q000276:immunology
chemical_list: D019158:N-Acetylneuraminic Acid
keywords: phagocytosis; sialic acid; sperm