Combined Chaetocin/Trichostatin A Treatment Improves the Epigenetic Modification and Developmental Competence of Porcine Somatic Cell Nuclear Transfer Embryos

Pil-Soo Jeong; Hae-Jun Yang; Soo-Hyun Park; Min Ah Gwon; Ye Eun Joo; Min Ju Kim; Hyo-Gu Kang; Sanghoon Lee; Young-Ho Park; Bong-Seok Song; Sun-Uk Kim; Deog-Bon Koo; Bo-Woong Sim

doi:10.3389/fcell.2021.709574

Combined Chaetocin/Trichostatin A Treatment Improves the Epigenetic Modification and Developmental Competence of Porcine Somatic Cell Nuclear Transfer Embryos

Front Cell Dev Biol. 2021 Oct 6:9:709574. doi: 10.3389/fcell.2021.709574. eCollection 2021.

Authors

Pil-Soo Jeong^{1

2}, Hae-Jun Yang¹, Soo-Hyun Park^{1

3}, Min Ah Gwon^{1

2}, Ye Eun Joo^{1

3}, Min Ju Kim^{1

3}, Hyo-Gu Kang^{1

4}, Sanghoon Lee¹, Young-Ho Park¹, Bong-Seok Song¹, Sun-Uk Kim^{1

5}, Deog-Bon Koo², Bo-Woong Sim¹

Affiliations

¹ Futuristic Animal Resource and Research Center (FARRC), Korea Research Institute of Bioscience and Biotechnology (KRIBB), Cheongju, South Korea.
² Department of Biotechnology, College of Engineering, Daegu University, Gyeongsan, South Korea.
³ Department of Animal Science, College of Natural Resources and Life Science, Pusan National University, Miryang, South Korea.
⁴ Department of Animal Science and Biotechnology, College of Agriculture and Life Science, Chungnam National University, Daejeon, South Korea.
⁵ Department of Functional Genomics, University of Science and Technology, Daejeon, South Korea.

Abstract

Developmental defects in somatic cell nuclear transfer (SCNT) embryos are principally attributable to incomplete epigenetic reprogramming. Small-molecule inhibitors such as histone methyltransferase inhibitors (HMTi) and histone deacetylase inhibitors (HDACi) have been used to improve reprogramming efficiency of SCNT embryos. However, their possible synergistic effect on epigenetic reprogramming has not been studied. In this study, we explored whether combined treatment with an HMTi (chaetocin) and an HDACi (trichostatin A; TSA) synergistically enhanced epigenetic reprogramming and the developmental competence of porcine SCNT embryos. Chaetocin, TSA, and the combination significantly increased the cleavage and blastocyst formation rate, hatching/hatched blastocyst rate, and cell numbers and survival rate compared to control embryos. In particular, the combined treatment improved the rate of development to blastocysts more so than chaetocin or TSA alone. TSA and combined chaetocin/TSA significantly reduced the H3K9me3 levels and increased the H3K9ac levels in SCNT embryos, although chaetocin alone significantly reduced only the H3K9me3 levels. Moreover, these inhibitors also decreased global DNA methylation in SCNT embryos. In addition, the expression of zygotic genome activation- and imprinting-related genes was increased by chaetocin or TSA, and more so by the combination, to levels similar to those of in vitro-fertilized embryos. These results suggest that combined chaetocin/TSA have synergistic effects on improving the developmental competences by regulating epigenetic reprogramming and correcting developmental potential-related gene expression in porcine SCNT embryos. Therefore, these strategies may contribute to the generation of transgenic pigs for biomedical research.

Keywords: chaetocin; epigenetic reprogramming; genomic imprinting; porcine embryonic development; somatic cell nuclear transfer (SCNT); trichostatin A (TSA); zygotic genome activation.