2011年3月23日我所高紹榮和朱冰實(shí)驗(yàn)室合作在 Stem Cells 雜志在線發(fā)表文章。該文首次提出了Rcor2-LSD1蛋白復(fù)合物在維持胚胎干細(xì)胞特性和誘導(dǎo)體細(xì)胞重編程為iPS細(xì)胞中的重要作用,。
核小體是染色質(zhì)的基本組成形式,,其組蛋白以八聚體結(jié)構(gòu)形式將真核細(xì)胞DNA包裝形成染色質(zhì),。在染色質(zhì)研究中,,人們發(fā)現(xiàn)組蛋白不僅僅起到包裝DNA的作用,,更起著真核轉(zhuǎn)錄表達(dá)調(diào)控的重要作用,。核小體不但能夠抑制轉(zhuǎn)錄,,更能夠通過(guò)改變?nèi)旧|(zhì)的狀態(tài)來(lái)影響轉(zhuǎn)錄,。胚胎干細(xì)胞的多能性與其染色體的特殊結(jié)構(gòu),尤其是組蛋白的修飾密切相關(guān),。LSD1作為最早發(fā)現(xiàn)的組蛋白去甲基化酶,,其在胚胎干細(xì)胞中的作用機(jī)理尚不清楚。該文報(bào)道了胚胎干細(xì)胞特異表達(dá)的Rcor2與LSD1形成致密的蛋白復(fù)合體,,專一性地抹去組蛋白H3第四位賴氨酸的甲基化,,沉默基因表達(dá)。進(jìn)一步的研究發(fā)現(xiàn),,Rcor2是干細(xì)胞維持多能性所必需的,,通過(guò)改變啟動(dòng)子表觀遺傳修飾抑制早期中胚層分化基因Brachyury的表達(dá)。另外,,在胚胎干細(xì)胞自我更新和體細(xì)胞重編程中,,Rcor2參與了維持多能基因Sox2的正常表達(dá),并在小鼠和人的體細(xì)胞重編程過(guò)程可取代Sox2誘導(dǎo)形成誘導(dǎo)多能干細(xì)胞(iPS細(xì)胞),。
我所與北京大學(xué)聯(lián)合培養(yǎng)的博士研究生楊鵬和我所與北京協(xié)和醫(yī)科大學(xué)聯(lián)合培養(yǎng)的博士研究生王譯萱為該文的共同第一作者,。高紹榮博士和朱冰博士為該文的共同通訊作者。其他作者還包括研究生陳嘉瑜,,康嵐,,技術(shù)員張郁以及我所蛋白質(zhì)中心的陳涉博士和工作人員李宏。此項(xiàng)研究由科技部及北京市資助,,在北京生命科學(xué)研究所完成,。(生物谷Bioon.com)
生物谷推薦原文出處:
STEM CELLS DOI: 10.1002/stem.634
Rcor2 is a Subunit of the LSD1 Complex that Regulates ES Cell Property and Substitutes for Sox2 in Reprogramming Somatic Cells to Pluripotency
Peng Yang, Yixuan Wang, Jiayu Chen, Hong Li, Lan Kang, Yu Zhang, She Chen, Bing Zhu, Shaorong Gao
Keywords:Histone demethylase;Rcor2;Pluripotency;Reprogramming
Abstract
Histone demethylase LSD1 can form complex with different Rcor family co-repressors in different cell types. It remains unknown if cell-specific Rcor proteins function specifically in distinct cell types. Here, we report that Rcor2 is predominantly expressed in ES cells and forms a complex with LSD1 and facilitates its nucleosomal demethylation activity. Knock-down of Rcor2 in ES cells inhibited ES cell proliferation and severely impaired the pluripotency. Moreover, knock-down of Rcor2 greatly impaired the formation of induced pluripotent stem (iPS) cells. In contrast, ectopic expression of Rcor2 in somatic cells together with Oct4, Sox2 and Klf4 promoted the formation of iPS cells. Most interestingly, ectopic expression of Rcor2 in both mouse and human somatic cells effectively substituted the requirement for exogenous Sox2 expression in somatic cell reprogramming.