Zhong Tao, Wang Cheng, Wang Meng, Zhan Siyuan, Freitas-de-Melo Aline, Wang Linjie, Cao Jiaxue, Dai Dinghui, Guo Jiazhong, Li Li, Zhang Hongping, Niu Lili
Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, China.
Departamento de Biociencias Veterinarias, Facultad de Veterinaria, Universidad de la República, Montevideo, Uruguay.
Front Physiol. 2022 Mar 30;13:858991. doi: 10.3389/fphys.2022.858991. eCollection 2022.
Circular RNAs (circRNAs) are key regulatory factors with vital functions in various biological activities. However, little has been reported concerning the genetic regulation of circRNAs during rumen development in goats. The aim of this study was to identify the genome-wide expression profiles of circRNAs in the rumen of goats during fetal development and before and after weaning. Histological morphology showed that from the fetal period (days 60 and 135 of gestation) to the prepuberal period (days 60 and 150 of age) the rumen papilla developed gradually, and the thickness of the rumen muscular layer increased. A total of 11,149 circRNAs were identified in the four development stages by RNA-sequencing. From this, 1,518 were differentially expressed circRNAs (DECs). Fifty-eight DECs were up-regulated from 60 to 135 days of gestation, and 93 from day 135 of pregnancy to 30 days after birth. A large proportion (598) of DECs were down-regulated from day 135 of gestation to 30 days after birth. The expression levels of six randomly selected circRNAs were validated by qPCR, and their back-splicing junction (BSJ) sites were also confirmed. Ontology and pathway analyses revealed that the parental genes of DECs were mainly involved in the signaling pathways related to cell proliferation and apoptosis. The interaction network of circRNAs with their target miRNAs showed its involvement in cell proliferation and apoptosis signaling pathways. In conclusion, we identified the genome-wide expression profiles of circRNAs in the rumen of goats during fetal development and before and after weaning. These results provide a basis for further study on the regulatory effect of circRNAs on the development of rumen tissues.
环状RNA（circRNAs）是在各种生物活动中具有重要功能的关键调控因子。然而，关于山羊瘤胃发育过程中circRNAs的遗传调控报道较少。本研究的目的是确定山羊胎儿发育期间以及断奶前后瘤胃中circRNAs的全基因组表达谱。组织学形态显示，从胎儿期（妊娠60天和135天）到青春期前（60日龄和150日龄），瘤胃乳头逐渐发育，瘤胃肌层厚度增加。通过RNA测序在四个发育阶段共鉴定出11,149个circRNAs。其中，1,518个是差异表达的circRNAs（DECs）。58个DECs在妊娠60至135天上调，93个在妊娠135天至出生后30天上调。很大一部分（598个）DECs在妊娠135天至出生后30天下调。通过qPCR验证了六个随机选择的circRNAs的表达水平，并确认了它们的反向剪接连接（BSJ）位点。本体和通路分析表明，DECs的亲本基因主要参与与细胞增殖和凋亡相关的信号通路。circRNAs与其靶miRNA的相互作用网络显示其参与细胞增殖和凋亡信号通路。总之，我们确定了山羊胎儿发育期间以及断奶前后瘤胃中circRNAs的全基因组表达谱。这些结果为进一步研究circRNAs对瘤胃组织发育的调控作用提供了依据。
