SIN3A Regulates Porcine Early Embryonic Development by Modulating CCNB1 Expression

Lei Luo; Yanna Dang; Yan Shi; Panpan Zhao; Yunhai Zhang; Kun Zhang

doi:10.3389/fcell.2021.604232

SIN3A Regulates Porcine Early Embryonic Development by Modulating CCNB1 Expression

Front Cell Dev Biol. 2021 Feb 22:9:604232. doi: 10.3389/fcell.2021.604232. eCollection 2021.

Authors

Lei Luo^{1

2}, Yanna Dang¹, Yan Shi¹, Panpan Zhao¹, Yunhai Zhang², Kun Zhang¹

Affiliations

¹ Laboratory of Mammalian Molecular Embryology, Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China.
² Anhui Provincial Laboratory of Local Livestock and Poultry Genetical Resource Conservation and Breeding, College of Animal Science and Technology, Anhui Agricultural University, Hefei, China.

Abstract

SIN3A is the central scaffold protein of the SIN3/histone deacetylase (HDAC) transcriptional repressor complex. SIN3A participates in the mouse preimplantation development by fine-tuning HDAC1 expression. However, it remains unresolved if this functional significance of SIN3A was conserved in other mammals. Herein, RNA-seq results show a large amount of SIN3A mRNA is present in oocytes and early embryos prior to embryonic genome activation and a low amount thereafter, suggesting a maternal origin of SIN3A in pigs, cattle, mice, and humans. Interestingly, immunofluorescence data show that SIN3A protein level peaks at four-cell stage in pigs compared with morula stage in cattle. SIN3A depletion in early embryos causes a developmental arrest at two-cell stage in pigs but does not affect bovine early embryonic development. In contrast with mouse data, SIN3A depletion results in only a slight decrease and even no difference in HDAC1 expression in porcine and bovine early embryos, respectively. In addition, HDAC1 knockdown does not cause two-cell block but leads to a reduced blastocyst rate. By using unbiased RNA-seq approach, we found that Cyclin B1 (CCNB1) transcript level is dramatically reduced. Moreover, CCNB1 knockdown results in a similar phenotype as SIN3A depletion. Injection of exogenous CCNB1 mRNA into SIN3A-depleted embryos could partly rescue embryonic development to pass two-cell stage. In conclusion, our results indicate SIN3A plays an essential role in porcine early embryonic development, which probably involves the regulation of CCNB1 expression.

Keywords: CCNB1; SIN3A; cattle; embryo; pig; preimplantation.