Zhang Xiaorui, Zhang Changquan, Zhou Di, Zhang Tianlei, Chen Xueqin, Ren Jinlin, He Caixia, Meng Fei, Zhou Qinwei, Yang Qiaohui, Dai Congling, Lin Ge, Zeng Sicong, Leng Lizhi
Hospital of Hunan Guangxiu, Hunan Normal University, Hunan 410001, China.
Reproductive and Genetic Hospital of Citic-Xiangya, Hunan 410008, China.
iScience. 2023 Feb 8;26(3):106158. doi: 10.1016/j.isci.2023.106158. eCollection 2023 Mar 17.
Zygotic genome activation (ZGA) is initiated once the genome chromatin state is organized in the newly formed zygote. Telomeres are specialized chromatin structures at the ends of chromosomes and are reset during early embryogenesis, while the details and significance of telomere changes in preimplantation embryos remain unclear. We demonstrated that the telomere length was shortened in the minor ZGA stage and significantly elongated in the major ZGA stage of human and mouse embryos. Expression of the ZGA pioneer factor was negatively correlated with the telomere length. ATAC sequencing data revealed that the chromatin accessibility peaks on the promoter region (i.e., the subtelomere of chromosome 4q) were transiently augmented in human minor ZGA. Reduction of telomeric heterochromatin H3K9me3 in the telomeric region also synergistically activated expression with p53 in human embryonic stem cells. We propose herein that telomeres regulate the expression of / through chromatin remodeling and are thereby involved in ZGA.
合子基因组激活（ZGA）在新形成的合子中基因组染色质状态得以组织时启动。端粒是染色体末端的特殊染色质结构，在早期胚胎发育过程中会重新设定，而植入前胚胎中端粒变化的细节和意义仍不清楚。我们证明，在人类和小鼠胚胎的小ZGA阶段端粒长度缩短，在大ZGA阶段显著延长。ZGA先驱因子的表达与端粒长度呈负相关。ATAC测序数据显示，在人类小ZGA中，启动子区域（即4号染色体q臂的亚端粒）上的染色质可及性峰短暂增强。端粒区域中端粒异染色质H3K9me3的减少也与人类胚胎干细胞中的p53协同激活表达。我们在此提出，端粒通过染色质重塑调节/的表达，从而参与ZGA。
