Sperm motility

About: Sperm motility is a research topic. Over the lifetime, 13874 publications have been published within this topic receiving 416587 citations. The topic is also known as: sperm movement & GO:0097722.

Semenogelin, the main protein of semen coagulum, inhibits human sperm capacitation by interfering with the superoxide anion generated during this process

Abstract: Semenogelin (Sg), the major protein of the human semen coagulum, is present at high concentrations in seminal vesicle secretions It is degraded by the prostate-specific antigen (PSA) to generate peptides of various biological activities that were found on and inside spermatozoa Our aim was to determine the effect of Sg on capacitation, which is the series of transformations that spermatozoa must undergo to become fertile At concentrations of 01 to 10 mg/mL (600- to 20-fold lower than those of semen), Sg did not affect sperm motility (%) but completely prevented capacitation induced by fetal cord serum ultrafiltrate; a partial inhibition of capacitation was noted with 003 mg Sg/mL There was also a dose-dependent decrease in the tyrosine phosphorylation of fibrous sheath proteins and in the O2--related chemiluminescence Ribonuclease (RNase), which has as high an isoelectric point (pI = 97) as Sg (pI = 95), also prevented sperm capacitation and O2--related chemiluminescence but to a lower extent, suggesting that one mechanism of Sg action on spermatozoa could be related to its positive charge at physiological pH Sg at 1, but not 03 or 01 mg/mL, scavenged the O2- generated by the mix of xanthine + xanthine oxidase and modified the kinetics of the reaction; RNase did not have such effects Therefore, Sg is a potential scavenger for O2- but probably also affects the sperm oxidase Spermatozoa rapidly processed Sg; a high proportion of Sg was degraded after 15 minutes of incubation The resulting polypeptide patterns were reminiscent of those obtained with PSA as a proteolytic enzyme These data suggest that Sg, its degradation products, or both may be natural regulators of sperm capacitation and could prevent this process from occurring prematurely One mechanism by which Sg acts could involve an interference with the O2- that is normally generated during this process

Deficiency of SPAG16L Causes Male Infertility Associated with Impaired Sperm Motility

Abstract: The axonemes of cilia and flagella contain a "9+2" structure of microtubules and associated proteins. Proteins associated with the central doublet pair have been identified in Chlamydomonas that result in motility defects when mutated. The murine orthologue of the Chlamydomonas PF20 gene, sperm-associated antigen 16 (Spag16), encodes two proteins of M(r) approximately 71 x 10(3) (SPAG16L) and M(r) approximately 35 x 10(3) (SPAG16S). In sperm, SPAG16L is found in the central apparatus of the axoneme. To determine the function of SPAG16L, gene targeting was used to generate mice lacking this protein but still expressing SPAG16S. Mutant animals were viable and showed no evidence of hydrocephalus, lateralization defects, sinusitis, bronchial infection, or cystic kidneys-symptoms typically associated with ciliary defects. However, males were infertile with a lower than normal sperm count. The sperm had marked motility defects, even though ultrastructural abnormalities of the axoneme were not evident. In addition, the testes of some nullizygous animals showed a spermatogenetic defect, which consisted of degenerated germ cells in the seminiferous tubules. We conclude that SPAG16L is essential for sperm flagellar function. The sperm defect is consistent with the motility phenotype of the Pf20 mutants of Chlamydomonas, but morphologically different in that the mutant algal axoneme lacks the central apparatus.