Human sperm contain similar amounts of protamine-1 (P1) and protamine-2 (P2). Although an aberrant protamine ratio have been observed in subfertile men, functional evidence is provided by protamine knockout mice exhibiting male infertility. As sperm DNA integrity is known to be linked with DNA fragmentation and apoptosis, we investigated whether the DNA fragmentation factor 40 (DFF40) ratio or ...

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. ...

DNA in mammalian, and most vertebrate sperm, is packaged by protamines into a highly condensed, biochemically inert form of chromatin. A model is proposed for the structure of this DNA-protamine complex which describes the site and mode of protamine binding to DNA and postulates, for the first time, specific inter- and intraprotamine interactions essential for the organization of this highly sp...

Chromomycin A3 binds to DNA and Protamine -deficient spermatozoa look bright yellow,whereas normal spermatozoa appear dull yellow.

In this study, we hypothesized that the life history traits of Leiothrix spiralis and L. vivipara would be linked to soil factors of the rupestrian grasslands and that rosette size would be influenced by soil moisture. Soil analyses were performed from five populations of L. spiralis and four populations of L. vivipara. In each area, three replicates were employed in 19 areas of occurrence of L...

Integrity of the sperm membrane, of which phosphatidyl serine (PS) plays a central role, is essential for fertilization. The externalisation of PS (EPS) occurs during capacitation and the acrosome reaction. EPS, from the inner to the outer membrane, is considered as a sign of early apoptosis. Therefore, EPS may have a dual function in sperm. This study has evaluated the relationship between EPS...

STUDY QUESTION Is there an association between sperm DNA damage, measured by three different assays, sperm nuclear protein content and clinical outcomes in assisted reproduction treatment (ART)? SUMMARY ANSWER Sperm DNA damage measured by terminal deoxynucleotidyltransferase-mediated dUTP nick-end labelling (TUNEL) and the Comet assay were significantly associated with ART outcomes in our sin...

Spermiogenesis includes transcriptional silencing, chromatin condensation and extensive morphological changes as spermatids transform into sperm. Chromatin condensation involves histone hyperacetylation, transitory DNA breaks, histone H2AX (also known as H2AFX) phosphorylation at Ser139 (γH2AX), and replacement of histones by protamines. Previously, we have reported that the spermatid protein k...

Background: Evaluation and comparison of total acrosin activity along with DNA integrity in the semen samples obtained from the varicocele individuals before and after the surgery and also in fertile individuals. Materials and Methods: Semen parameters, protamine deficiency, DNA fragmentation and Total acrosin activity were measured in patients with a clinical diagnosed varicocele of grade II o...

By means of qualitative staining experiments the characteristic protein changes which occur during maturation of salmon sperm can be followed. It can be observed that the replacement of histone by protamine takes place after completion of meiosis during an advanced stage of spermiogenesis.