RÉSUMÉ
Developmental programming of the embryo is controlled by both genetic information and epigenetic information. During fertilization, this information carried by sperms can be delivered to thezygote, where they can regulate early embryonic development. Mature sperms are highly abundant in epigenetic information, and including small non-coding RNAs (sncRNAs), which play important roles during spermatogenesis, fertilization, and early embryo development. Recent studies revealed that sncRNAs can regulate gene expression, mediate protein translation, transmit the epigenetic information, and so on. Recently, increasing evidences showed that parental environment exposure, such as diet, toxicant, pressure, may cause the inheritance of acquired characteristics, and they can be stored and transmitted to the next generation by epigenetic information in germ cells. Recent advances of transgenerational inheritance revealed that sncRNAs are environmentally responsive epigenetic molecules in sperms. This review summarized current knowledge about the sncRNAs information in sperms, including transfer RNA-derived small RNAs (tsRNAs), rsRNAs (risbosome-RNA derived small RNAs), microRNAs (miRNAs) and PIWI-interacting RNAs (piRNAs), that are responsive to environmental factors and are capable of affecting embryonic development and the phenotype of the offspring later in life. Furthermore, this review also delineated potential molecular mechanisms that might regulate sperm sncRNAs.
RÉSUMÉ
The mammalian epididymis not only plays a fundamental role in the maturation of spermatozoa, but also provides protection against various stressors. The foremost among these is the threat posed by oxidative stress, which arises from an imbalance in reactive oxygen species and can elicit damage to cellular lipids, proteins, and nucleic acids. In mice, the risk of oxidative damage to spermatozoa is mitigated through the expression and secretion of glutathione peroxidase 5 (GPX5) as a major luminal scavenger in the proximal caput epididymidal segment. Accordingly, the loss of GPX5-mediated protection leads to impaired DNA integrity in the spermatozoa of aged Gpx5