Kisspeptins are a family of overlapping neuropeptides encoded by the Kiss1 gene that regulate the mammalian reproductive axis by a central action in the hypothalamus to stimulate GnRH release. Kisspeptins and their receptor (GPR54 also called KISS1R) are also expressed in the testes but a functional role in this tissue has not been confirmed. We examined which cell types in the testes expressed...

Androgen receptor function is required for male embryonic sexual differentiation, pubertal development and the regulation of spermatogenesis in mammals. During spermatogenesis, this requirement is thought to be mediated by Sertoli cells and its genetic and pharmacological disruption is manifested in spermatocytes as meiotic arrest. Through studies of a hypomorphic and conditional allele of the ...

Previous studies on the epigenetic regulator DNA methyltransferase 3-Like (DNMT3L), have demonstrated it is an essential regulator of paternal imprinting and early male meiosis. Dnmt3L is also a paternal effect gene, i.e., wild type offspring of heterozygous mutant sires display abnormal phenotypes suggesting the inheritance of aberrant epigenetic marks on the paternal chromosomes. In order to ...

cAMP response element modulator (CREM) is an important component of the cAMP-mediated signaling pathway and is essential for differentiation of haploid male germ cells. In the rodent, testicular expression of CREM is believed to be controlled by FSH. We studied the expression pattern of CREM and gonadotropic control in the nonhuman primate and rodent testis. Adult cynomolgus monkeys (Macaca fas...

In metazoan organisms, cytokinesis is initially driven by the purse-string-like constriction of an actomyosin-based contractile ring and its associated plasma membrane. At the end of cytokinesis, the contractile ring disassembles and the two daughter cells separate (reviewed in Satterwhite and Pollard, 1992; Fishkind and Wang, 1995). Although a large number of protein effectors of cytokinesis h...

To assess whether changes in spermatogenesis are present in men suffering from varicocele who are still normospermic, a comparative flow cytometric analysis of the left and right testicular DNA content was performed on 26 young normospermic males (sperm density > 20 x 10(6)/ml), with varying degrees of asthenospermia. Cell samples were obtained by fine needle aspiration biopsy. Flow cytometric ...

S permatogenesis is a tightly regulated process of development for the generation of mature spermatozoa. Mammalian spermatogenesis occurs in the convoluted seminiferous tubules of the testes, where spermatogenic stem cells (SSCs) reside on sustentacular Sertoli cells of somatic origin, forming a germinal epithelial structure. Spermato genesis is accomplished in a complicated, timely controlled ...

Studies of the reproductive biology of the nematode Caenorhabditis elegans are providing valuable insights into the evolution and diversity of reproductive strategies [1,2]. The successful production of progeny in any species also highlights many fundamental problems in cell biology. Research on the amoeboid sperm of nematodes addresses a number of issues of broad biological significance, inclu...