Cysteine oxidation in protamines leads to their oligomerization and contributes to sperm chromatin compaction. Here we identify the Drosophila thioredoxin Deadhead (DHD) as the factor responsible for the reduction of intermolecular disulfide bonds in protamines and their eviction from sperm during fertilization. Protamine chaperone TAP/p32 dissociates DNA-protamine complexes in vitro only when ...

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...

The mammalian spermatozoon has a unique chromatin structure where the majority of DNA is packaged by protamines, while a small fraction (∼8%) remains associated with nucleosomes. However, the chromatin affinity and repertoire of the additional proteins constituting the different sperm chromatin fractions have not yet been explored. To address this we have carried out a genomic and proteomic cha...

tau.amegroups.com © Translational Andrology and Urology. All rights reserved. Male factor subfertility is present in more than 50% of the couples treated with assisted reproductive techniques. Routine semen analysis provides information on semen volume as well as sperm concentration, motility, and morphology. Standardized methods have been published by the World Health Organization (WHO) (1). N...

Background: Cytoplasm and mitochondria are considered as the major origins of sperm ROS production. Sperm is prone to DNA damage by exposure to ROS or due impaired chromatin remodeling or low DNA protamination. Therefore, the aim of this study was to see if there is any association between impaired chromatin packaging and origin of ROS production. Materials and Methods: Cytosolic ROS, mitochond...

Sperm chromatin/DNA damage can be measured by a variety of assays. However, it has been reported that these tests may lose prognostic value in Assisted Reproductive Technology (ART) cycles when assessed in post-prepared samples, possibly due to the normalizing effect promoted by sperm preparation procedures. We have recently implemented a modified version of the Diff-Quik staining assay that al...

Sperm chromatin integrity has been being recognized as an important factor in male fertility. During normal fertilization, high quality sperm with intact chromatin are selected through natural selection in journey from vagina to fallopian tube. However, using Assisted Reproductive Techniques, particularly ICSI, the natural selection is bypassed. Therefore sperm with DNA breakage have the opport...

background: it is estimated that about 50% of causes of recurrent pregnancy loss (rpl) cases remain unknown. sperm factors are suggested to have probable role in cases with rpl. objective: the goal was to determine the possible relationship between semen bacterial contaminations with unexplained rpl. also, the correlation between number of bacterial colony and sperm chromatin condensation was e...