Abd El Naby, Walaa Slouma Hamouda: Expression analysis of regulatory MicroRNA in bovine cumulus oocyte complex and preimplantation embryos. - Bonn, 2012. - Dissertation, Rheinische Friedrich-Wilhelms-Universität Bonn.
Online-Ausgabe in bonndoc: https://nbn-resolving.org/urn:nbn:de:hbz:5n-28566
urn: https://nbn-resolving.org/urn:nbn:de:hbz:5n-28566,
author = {{Walaa Slouma Hamouda Abd El Naby}},
title = {Expression analysis of regulatory MicroRNA in bovine cumulus oocyte complex and preimplantation embryos},
school = {Rheinische Friedrich-Wilhelms-Universität Bonn},
year = 2012,
month = jun,

volume = 160,
note = {MicroRNAs (miRNAs) are small non coding endogenous molecules which participate in gene regulation post transcriptionally. These small RNAs are shown to be involved in a wide range of biological processes including development, cell differentiation, cell proliferation and apoptosis in diverse organisms. However, little is known about their abundance in bovine oocytes and their surrounding cumulus cells during oocyte development. To elucidate this, we investigated the relative expression pattern of a set of 88 miRNAs between bovine oocytes and the surrounding cumulus cells during in vitro maturation, using miRNA PCR array related to human cell development and differentiation. Results revealed a total of 47 and 51 miRNAs to be differentially expressed (p ≤ 0.05 and fold change ≥ 2) between immature (GV) and matured (MII) oocytes, respectively compared to their surrounding cumulus cells. However, 8 and 6 miRNAs were found to be highly abundant in cumulus cells compared to oocytes at immature and matured stages, respectively. The expression analysis of six oocytes enriched miRNAs (miR-205, -150, -122, -96, -146a and -146b-5p) in bovine preimplantation embryo stages was performed. Results showed that expression of these miRNAs were highly abundant in early stages of embryo development and reduced after 8-cell until the blastocyst stage following a typical maternal transcript profile. Comparable results were obtained by in situ localization of miR-205 in preimplantation embryo stages. However, the two selected miRNAs enriched in cumulus cells (miR-210 and miR-452) showed no defined profile. The same eight miRNAs were detected at high level in fully grown oocyte (BCB+) compared to growing one (BCB-). Interestingly, the presence or absence of oocytes or cumulus cells during maturation was found to affect the expression of selected miRNAs in each of the two cell types. Furthermore, miR-205 and miR-210 were in situ localized in ovarian follicle and revealed a spatio-temporal expression during follicular development. Hence, our results evidenced the presence of distinct set of miRNAs in oocytes and cumulus cells which may have potential role in regulation of bidirectional communication between the two cell types. Moreover, maternal miRNAs were found to persist until the major genome activation in bovine.},
url = {https://hdl.handle.net/20.500.11811/5105}

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