The m6A methylation regulates gonadal sex differentiation in chicken embryo
m6A 메틸화는 닭 배아에서 생식선 성 분화를 조절합니다
La metilación de m6A regula la diferenciación sexual gonadal en embrión de pollo
La méthylation m6A régule la différenciation sexuelle gonadique chez l'embryon de poulet
Метилирование m6A регулирует половую дифференцировку гонад у куриных эмбрионов
Jianbo Li ¹, Xiuan Zhang ¹, Xiqiong Wang 王喜琼 ¹, Congjiao Sun 孙从佼 ¹, Jiangxia Zheng 郑江霞 ¹, Junying Li 李俊英 ¹, Guoqiang Yi 易国强 ², Ning Yang 杨宁 ¹
¹ National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture and Rural Affairs, China Agricultural University, Beijing, China
中国 北京 中国农业大学畜禽育种国家工程实验室 农业农村部动物遗传育种与繁殖（家畜）重点实验室
² Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
中国 深圳 中国农业科学院深圳农业基因组研究所 岭南现代农业科学与技术广东省实验室深圳分中心
Journal of Animal Science and Biotechnology, 18 May 2022
As a ubiquitous reversible epigenetic RNA modification, N6-methyladenosine (m6A) plays crucial regulatory roles in multiple biological pathways. However, its functional mechanisms in sex determination and differentiation during gonadal development of chicken embryos are not clear. Therefore, we established a transcriptome-wide m6A map in the female and male chicken left gonads of embryonic day 7 (E7) by methylated RNA immunoprecipitation sequencing (MeRIP-seq) to offer insight into the landscape of m6A methylation and investigate the post-transcriptional modification underlying gonadal differentiation.
The chicken embryonic gonadal transcriptome was extensively methylated. We found 15,191 and 16,111 m6A peaks in the female and male left gonads, respectively, which were mainly enriched in the coding sequence (CDS) and stop codon. Among these m6A peaks, we identified that 1013 and 751 were hypermethylated in females and males, respectively. These differential peaks covered 281 and 327 genes, such as BMP2, SMAD2, SOX9 and CYP19A1, which were primarily associated with development, morphogenesis and sex differentiation by functional enrichment. Further analysis revealed that the m6A methylation level was positively correlated with gene expression abundance. Furthermore, we found that YTHDC2 could regulate the expression of sex-related genes, especially HEMGN and SOX9, in male mesonephros/gonad mingle cells, which was verified by in vitro experiments, suggesting a regulatory role of m6A methylation in chicken gonad differentiation.
This work provided a comprehensive m6A methylation profile of chicken embryonic gonads and revealed YTHDC2 as a key regulator responsible for sex differentiation. Our results contribute to a better understanding of epigenetic factors involved in chicken sex determination and differentiation and to promoting the future development of sex manipulation in poultry industry.