Abstract
Luteinizing hormone (LH) plays a key role in the control of physiological processes such as follicle development, ovulation and luteal maintenance in the ovary acting via, LHR. The LHR expression in bovine granulosa cells is crucial for the transition of FSH/LH-dependency in antral follicles. In cattle during the growth and differentiation of granulosa cells, there is an increase on LHR mRNA abundance. Among several factors that control the ovarian development, there is an involvement of microRNAs (miRNAs). MiRNAs are small no-coding RNA molecules composed by 19-25 base pairs that control the cellular translation. Studies have characterized the presence and dual actions of miRNAs in mammalian female reproductive tract, including, deleterious effects on female fertility, as the reduction in ovulatory capacity. Inversely, there is a pro-follicular effect, as inhibition of apoptosis in ovarian follicular by in vivo administration of miRNAs. In cattle, some studies have identified the profile of miRNAs expressed in adult and fetal ovaries and characterized the regulatory effect of miRNAs on mRNA targets involved in ovarian follicular differentiation, but not in the context aimed in this work. Thus, this project using four integrated experiments, aims to investigate and characterize the profile of miRNAs expressed in the theca and granulosa cells during follicle deviation in Nelore heifers, as well as its regulation by pro-survival factors for follicles (IGF1) and gonadotropins (FSH and eCG) used in pharmacological strategies for control of the estrous cycle in cattle. Additionally, we intend to evaluate in vitro actions of miRNAs on the differentiation and steroidogenesis of ovarian follicular cells (granulosa cells) with focus on regulation of LHR expression. Therefore, it is expected that the compilation of the results generated by this study may be identify new targets for enhanced reproductive efficiency in cattle different pharmacological on strategies for the manipulation of the estrus cycle, producing a "molecular signature" of miRNAs required for the development of the follicle dominant in Nellore females, stimulating, perhaps, the development of molecular therapies through the use of miRNAs (in situ) to post transcriptional regulation in the bovine ovary in females of low fertility. (AU)
| Articles published in Agência FAPESP Newsletter about the research grant: |
| More itemsLess items |
| TITULO |
| Articles published in other media outlets ( ): |
| More itemsLess items |
| VEICULO: TITULO (DATA) |
| VEICULO: TITULO (DATA) |