Endocrine Abstracts

We are the first who studied the control and the role of transcription factors in the regulation of reproductive functions. Our presentation represents a short review of original data concerning external (temperature, calories restriction) and internal (hormones, protein kinases, RNA interference) in control of selected transcription factors (p53, NFkB, STAT1, CREB1), as well as their role in control of basic ovarian cell functions (proliferation, apoptosis, secretory activity, response to hormonal stimulators). It was shown, that stress (high temperatures, food restriction), hormonal regulators of reproduction (gonadotropins, GH, oxytocin, some growth factors), pharmacological or genomic regulators of protein kinases (protein kinase A, MAP kinase, CDC2 and other kinases), si RNAs and miRNAs control the expression of these transcription factors within porcine, rabbit and human ovarian cells. Furthermore, the transfection-induced overexpression of these transcription factors altered the proliferation (markers of cell cycle PCNA, cyclin B1, MAP kinase, CDC2 kinase/p34), both nuclear (TdT) and cytoplasmic (bax, bcl-2, caspase 3, p53) apoptosis, release of steroid (progesterone, testosterone, estradiol) and peptide (oxytocin, IGF-I) hormones and prostaglandins (F and G) by cultured ovarian granulosa cells, as well as their response to stress and hormonal treatments. Comparison of cDNA constructs encoding phosphorylable and non-phosphorylable CREB1 showed no substantial differences in their action on the majority of analyzed ovarian functions. These observation demonstrate (1) the presence of transcription factors in ovarian cells, (2) the hierarchy of upstream regulators of ovarian transcription factors (environmental factors – hormones-protein kinases – miRNA – transcription factors), (3) the involvement of transcription factors in control of basic ovarian cell functions (proliferation, apoptosis, secretory activity and response to hormones), and (4) that phosphorylation of some transcription factors is not necessary for their action.