background: stress is a cause of male infertility. although sex hormones and sperm quality have been shown to be low in stress, sperm physiology and testicular functional proteins, such as phosphotyrosine proteins, have not been documented. objective: to investigate the acrosome status and alterations of testicular proteins involved in spermatogenesis and testosterone synthesis in chronic stres...

The bovine gene for the steroidogenic acute regulatory protein (StAR) was cloned and sequenced, including 2 kb of the upstream control region of the gene. The gene comprises seven exons arranged similarly to those of the human and mouse gene sequences. The sequence analysis identified three cis elements corresponding to the binding motif for the transcription factor SF-1/Ad4BP, at - 100, - 240 ...

Transcriptional regulation of the steroidogenic acute regulatory (StAR) protein gene by cAMP-dependent mechanisms occurs in the absence of a consensus cAMP-response element (CRE; TGACGTCA) and is mediated by several sequence-specific transcription factors. We previously identified three CRE-like sites (within the -151/-1 bp cAMP-responsive region of the mouse StAR gene), of which the CRE2 site ...

BACKGROUND Until recently, the corpus luteum (CL) was considered to be the main source of progesterone (P4) during pregnancy in the domestic cat (Felis catus). However, other possible sources of P4 have not been ruled out. Although feline placental homogenates were found to be capable of synthesizing P4, expression of the respective steroidogenic enzymes has not been investigated at the molecul...

The steroidogenic acute regulatory (StAR) protein-related lipid transfer (START) domain proteins constitute a family of evolutionarily conserved and widely expressed proteins that have been implicated in lipid transport, metabolism, and signaling. The 15 well-characterized mammalian START domain-containing proteins are grouped into six subfamilies. The START domain containing 7 mRNA encodes Sta...

Interferon-gamma (IFNgamma) is an immunomodulating cytokine that has profound effects on reproductive function. IFNgamma inhibits steroidogenesis both in vivo and in vitro. The mechanism by which IFNgamma inhibits Leydig cell steroidogenesis remains unclear. In the present study, we evaluated the effect of IFNgamma on the expression and regulation of the steroidogenic acute regulatory protein (...

In adrenocortical cells, adrenocorticotropin (ACTH) promotes the activation of several protein kinases. The action of these kinases is linked to steroid production, mainly through steroidogenic acute regulatory protein (StAR), whose expression and activity are dependent on protein phosphorylation events at genomic and non-genomic levels. Hormone-dependent mitochondrial dynamics and cell prolife...