克服H3K27me3印跡障礙可提高體細胞核轉移克隆效率
作者:
小柯機器人發布時間:2020/6/22 10:57:43
中科院動物研究所周琪、李偉、中科院遺傳與發育生物學研究所陸發隆等研究人員合作發現,克服固有的H3K27me3印跡障礙能夠改善體細胞核移植後的著床後發育。該項研究成果於2020年6月18日在線發表在《細胞—幹細胞》雜誌上。
研究人員發現,通過從單倍體小鼠胚胎幹細胞中同時攜帶四個H3K27me3印跡基因的單等位基因缺失體細胞供體細胞可顯著提高體細胞核移植(SCNT)效率。 Sfmbt2、Jade1、Gab1和Smoc1的四重單等位基因缺失可正常化H3K27me3印跡的表達模式,並將成纖維細胞克隆效率提高至14%,而野生型成纖維細胞的出生率為0%,同時防止了在克隆動物中經常觀察到的胎盤和身體過度生長缺陷動物。在改善SCNT方面,Sfmbt2缺失是四個單獨基因缺失中最有效的。
這些結果表明,體細胞中H3K27me3印跡的缺乏是表觀遺傳障礙,阻礙了SCNT胚胎植入後的發育,可以通過供體細胞中的單等位基因印跡基因缺失來克服。
據了解,通過SCNT成功克隆需要克服重要的表觀遺傳障礙。儘管H3K27me3依賴型印跡在E6.5外胚層和胚外組織中差異分布,但基因組印跡通常不被視為此類障礙。
附:英文原文
Title: Overcoming Intrinsic H3K27me3 Imprinting Barriers Improves Post-implantation Development after Somatic Cell Nuclear Transfer
Author: Le-Yun Wang, Zhi-Kun Li, Li-Bin Wang, Chao Liu, Xue-Han Sun, Gui-Hai Feng, Jia-Qiang Wang, Yu-Fei Li, Lian-Yong Qiao, Hu Nie, Li-Yuan Jiang, Hao Sun, Ya-Li Xie, Si-Nan Ma, Hai-Feng Wan, Fa-Long Lu, Wei Li, Qi Zhou
Issue&Volume: 2020-06-18
Abstract: Successful cloning by somatic cell nuclear transfer (SCNT) requires overcoming significantepigenetic barriers. Genomic imprinting is not generally regarded as such a barrier,although H3K27me3-dependent imprinting is differentially distributed in E6.5 epiblastand extraembryonic tissues. Here we report significant enhancement of SCNT efficiencyby deriving somatic donor cells carrying simultaneous monoallelic deletion of fourH3K27me3-imprinted genes from haploid mouse embryonic stem cells. Quadruple monoallelicdeletion of Sfmbt2, Jade1, Gab1, and Smoc1 normalized H3K27me3-imprinted expression patterns and increased fibroblast cloningefficiency to 14% compared with a 0% birth rate from wild-type fibroblasts while preventingthe placental and body overgrowth defects frequently observed in cloned animals. Sfmbt2 deletion was the most effective of the four individual gene deletions in improvingSCNT. These results show that lack of H3K27me3 imprinting in somatic cells is an epigeneticbarrier that impedes post-implantation development of SCNT embryos and can be overcomeby monoallelic imprinting gene deletions in donor cells.
DOI: 10.1016/j.stem.2020.05.014
Source: https://www.cell.com/cell-stem-cell/fulltext/S1934-5909(20)30212-5