It is believed that the transition proteins (Tnp1 and Tnp2) participate in the removal of the nucleohistones and in the initial condensation of the spermatid nucleus. Later in spermatogenesis, Tnp1 and Tnp2 are replaced by the protamines 1 and 2. In an effort to elucidate the physiological role of Tnp2, we have disrupted its locus by homologous recombination. Breeding of the Tnp2(-/-) males on ...

Mammalian spermiogenesis is marked by the morphological and functional differentiation of round haploid spermatids into mature spermatozoa. A molecular restructuring of the chromatin accompanies this process facilitated by the transition proteins and protamines which compact and condense the genetic material within the developing spermatid. Previous studies from this laboratory have demonstrate...

Transition protein 2 (TNP2) participates in removing nucleohistones and the initial condensation of spermatid nucleus during spermiogenesis. This study investigated the relationship between the variants of the bovine TNP2 gene and the semen quality traits of Chinese Holstein bulls. We detected three single nucleotide polymorphisms (SNPs) of the TNP2 gene in 392 Chinese Holstein bulls, namely, g...

OBJECTIVE(S) Transplantation quality improvement and reduction of cellular damage are important goals that are now considered by researchers. Melatonin is secreted from the pineal gland and some organs such as testes. According to beneficial effects of melatonin (such as its antioxidant and antiapoptotic properties), researchers have proposed that the use of melatonin may improve transplantatio...

The packaging of the male haploid genome within the differentiating spermatid nucleus is facilitated by small basic nuclear proteins called protamines. Although the majority of the DNA in human sperm chromatin is bound by these proteins, a small percentage retains a nucleosomal-like component. These histone-enriched regions may possess enhanced nuclease sensitivity and have been postulated to d...

BACKGROUND Histones are replaced by protamines to condensate and package DNA into the sperm head during mammalian spermatogenesis. Protamine genes defects have been reported to cause sperm DNA damage and male infertility. OBJECTIVE In this study relationship among some protamines genes family SNPs include PRM1 (C321A), PRM2 (C248T) and TNP2 (T1019C), (G1272C), (G del in 1036 and 1046 bp) were...