The Functions And Mechanisms Of Odf Family Proteins In Asthenospermia

Background and Objectives Asthenospermia used to cause male infertility,while the etiology of asthenospermia is still unclear,resulting a poor drug treatment effect to the disease.The outer dense fibers(ODFs)are mammalian specific cytoskeleton,which wrap around the outer space of sperm axoneme.Previous studies suggest that it can passively protect the integrity of the sperm tail structure.Odf family proteins are the main components of ODFs.Studies show that abnormal Odf family proteins can lead to the defect of sperm tail structure.However,while there is little research about correlation between Odf family proteins,ODFs and sperm motility.Thus,in this study,tissues,cell line and animal test are used to analyze expression character and biological effects of Odf family proteins in asthenospermia,reveal the mechanism of Odf family proteins regulating the construction of ODFs and the effect on sperm motility,and then provide scientific basis for the treatment of asthenospermia.Materials and Methods 1.Semen samples were collected from normal humans,asthenospermia patients and three mammals.The abnormal structure of sperm tail and the expression characteristics of Odf family proteins were detected,and the correlation among ODFs,sperm length and sperm motility were also analyzed.2.The expressions and localizations of Odf family proteins were explored.Odf2 conditional knockout mouse model was made to detect the expression characteristics of mouse sperm structure and the expression of Odf2 protein;lithium chloride was used to dispose the mice,then the relevance between the expression of Odf family protein and and acetylated tubulin,together with activity of sperm protein were detected.3.Cfap58,which was identified by co-IP and protein mass spectrometry,interacted with Odf2 in the construction of ODFs;the expression,function and mechanism of Cfap58 in vivo and in vitro was confirmed by molecular and pharmacological experiments.Results 1.The percentage of defective ODFs was higher in asthenospermic samples than that in control samples and was significantly correlated with the percentage of axoneme defects;the expression levels of Odf family proteins were frequently down-regulated in asthenospermic samples;the positive relationship between size of ODFs and sperm motility existed in species.2.Conditional disruption of Odf2 expression in mice led to reduced sperm motility and the characteristics of asthenozoospermia;Odf2 was able to bind to acetylated ?-tubulin and protect the acetylation level of ?-tubulin in a cold environment;lithium elevated the expression levels of Odf family proteins and acetylated ?-tubulin as well as elongated the midpiece length and increased the percentage of motile sperm in mice.3.Cfap58 interacted with Odf2 protein and participated in the construction of ODFs;Cfap58 might promote cilium formation by Notch pathway.Conclusions1.Odf family proteins interact with acetylated ?-tubulin to stabilize the sperm axoneme and maintain the movement of the sperm.2.The interaction of Cfap58 and Odf2 protein participates in the construction of outer dense fibers and regulates ciliogenesis via Notch pathway.