Proteomic analysis of proteins involved in spermiogenesis in mouse.
Spermiogenesis is a unique process in mammals during which haploid round spermatids mature into spermatozoa in the testis. Its successful completion is necessary for fertilization and its malfunction is an important cause of male infertility. Here, we report the high-confidence identification of 2116 proteins in mouse haploid germ cells undergoing spermiogenesis: 299 of these were testis-specific and 155 were novel. Analysis of these proteins showed many proteins possibly functioning in unique processes of spermiogenesis. Of the 84 proteins annotated to be involved in vesicle-related events, VAMP4 was shown to be important for acrosome biogenesis by in vivo knockdown experiments. Knockdown of VAMP4 caused defects of acrosomal vesicle fusion and significantly increased head abnormalities in spermatids from testis and sperm from the cauda epididymis. Analysis of chromosomal distribution of the haploid genes showed underrepresentation on the X chromosome and overrepresentation on chromosome 11, which were due to meiotic sex chromosome inactivation and expansion of testis-expressed gene families, respectively. Comparison with transcriptional data showed translational regulation during spermiogenesis. This characterization of proteins involved in spermiogenesis provides an inventory of proteins useful for understanding the mechanisms of male infertility and may provide candidates for drug targets for male contraception and male infertility.
Guo
Xuejiang
X
Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing 210029, China.
Shen
Jian
J
Xia
Zhengrong
Z
Zhang
Rui
R
Zhang
Ping
P
Zhao
Chun
C
Xing
Jun
J
Chen
Ling
L
Chen
Wen
W
Lin
Min
M
Huo
Ran
R
Su
Bing
B
Zhou
Zuomin
Z
Sha
Jiahao
J
D000177:Acrosome / Q000378:metabolism*; D000818:Animals; D016009:Chi-Square Distribution; D002923:Cilia / Q000378:metabolism; D005786:Gene Expression Regulation; D055785:Gene Knockdown Techniques; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D011506:Proteins / Q000235:genetics / Q000378:metabolism; D040901:Proteomics / Q000379:methods*; D050683:R-SNARE Proteins / Q000235:genetics / Q000378:metabolism; D018626:Retroelements; D015398:Signal Transduction; D013091:Spermatogenesis / Q000502:physiology*; D013094:Spermatozoa / Q000166:cytology / Q000378:metabolism
D011506:Proteins; D050683:R-SNARE Proteins; D018626:Retroelements; C476457:Vamp4 protein, mouse