Background During mammalian spermatogenesis unique and dynamic epigenetic events occur leading to chromatin condensation. Through these events, histone demethylases such as JMJD1A play important roles in compaction of sperm chromatin, due to regulation of histone methylation dynamics and alteration of chromatin structure. As �histone methylation� is one of the best-characterized modifications i...

Background: Selection of human spermatozoa prior to assisted reproduction is currently based on motility and morphology. Recently, Zeta method has been introduced for normal sperm selection based on sperm surface charges. In addition, one of the features of apoptosis is the externalization of phosphatidylserine (PS), which are normally present on the inner leaflet of the sperm plasma membrane. ...

Research on the functional properties of nucleosome structure and composition dynamics has revealed that chromatin-level regulation is an essential component of light signalling and clock function in plants, two processes that rely extensively on transcriptional controls. In particular, several types of histone post-translational modifications and chromatin-bound factors act sequentially or in ...

A critical part of generating robust chromatin immunoprecipitation (ChIP) data is the optimization of chromatin purification and size selection. This is particularly important when ChIP is combined with next-generation sequencing (ChIP-seq) to identify targets of DNA-binding proteins, genome-wide. Current protocols refined by the ENCODE consortium generally use a two-step cell lysis procedure t...

Background: Infertility is a complex medical problem. About 15% of couples are infertile, and male infertility being involved in roughly 50% of the cases. Among these, many cases are associated with a severe impairment of spermatogenesis. During the last stage of spermatogenesis (spermiogenesis), sperm chromatin endures complex modifications in which histones are lost and depositioned with tran...

Background: Chronic ethanol abuse causes reproductive organ failure and infertility in both humans and laboratory animals. Since sperm has a critical role in reproductive function, the objective of this unique study was to evaluate the effects of different doses of ethanol on sperm parameters, chromatin structure and apoptosis in adult mice. Materials and Methods: A total of 36 adult male mice ...

BACKGROUND Exposures to lead above the threshold value of 50-60 μg/dL have been linked to diminished semen quality parameters. Worldwide, the lead exposure has been diminished during the last years. Therefore, it has become of a great concern to examine the effects of lead exposures on semen quality at low levels of exposure. OBJECTIVE To evaluate the effect of low level (<20 μg/dL) blood lea...

Background: There has been a growing claim that cell phone usage may have a detrimental effect on sperm chromatin. Infertile men possess anomalies in the composition of their sperm nuclei, displaying higher levels of loosely packaged chromatin and damaged DNA. In this study we examined the relationship of cell phone radiation and the protection effect of alpha_tocopherol on human sperm DNA. Mat...

Background The aim of present study is to evaluate the effect of PolyVinyl Pyrrolidone (PVP) routinly used during ICSI procedure on sperm membrane integrity, and sperm chromatin status. MaterialsAndMethods This study was carried out on 21 semen samples from the infertile men referring to Isfahan Fertility and Infertility Center. The processed semen samples were divided into two portions. One po...