Quantitative analysis of RNA abondance for CTCF during reprogramming of bovine embryo from oocyte to blastocyst

M Amiri Roudbar,M Tahmoorespur,S Ansari Majd,H Adeldust,A Zahmatkesh,M Daliri Joupari,H Dehghani

doi:10.5194/aab-58-171-2015

Abstract

Abstract. CTCF is a highly conserved protein among eukaryotes and it is involved in many of regulatory functions including, transcriptional repression and activation, chromatin insulation, imprinting, X chromosome inactivation, higher-order chromatin organization, and alternative splicing. Studies performed on mouse embryos indicate that CTCF can be a maternal-effect gene, and is essential for normal development of embryos. CTCF can be used as a molecular effector for the proper epigenetic establishment of embryonic development. The aim of this study was to determine changes in transcript levels of the CTCF gene in bovine preimplantation embryos. RNA was extracted from immature and mature oocytes and embryos at various developmental stages (two-cell, four-cell, eight-cell, and blastocysts). Results showed that the amounts of CTCF transcripts decreased in mature oocyte in comparison with immature oocytes, but this change was not significant. In addition, the amount of CTCF transcript in embryos at two-cell, four-cell, eight-cell, and blastocyst stages significantly increased in comparison with immature oocytes. These data show that CTCF expression in bovine embryo begins at minor embryonic genome activation.

Highlights

Linear models of studies on gene expression has developed and changed into three-dimensional models of gene expression profiling
Maternal-effect genes are necessary for normal embryonic development (Wan et al, 2008)
Depletion of the CCCTC binding factor (CTCF) caused many of genes to become misregulated at early stages of embryogenesis

Summary

Introduction

Linear models of studies on gene expression has developed and changed into three-dimensional models of gene expression profiling. These studies suggest the existence of factors that have roles in higher-order chromatin organization. CTCF is a good candidate to play this important role. These findings have led to recognizing this protein as a master weaver of the genome (Phillips and Corces, 2009). Existence of 39 609 binding sites in the genome of mouse embryonic stem cells and 28 661, 19 308, and 19 572 binding sites in the genome of human CD4+T cells, HeLa cells, and Jurkat cells, respectively, for CTCF illustrates a very important role for this binding protein (Cuddapah et al, 2009; Chen et al, 2008)

Objectives

Methods

Results

Conclusion