日本產(chǎn)業(yè)技術(shù)綜合研究所日前發(fā)布公報(bào)說,，該所科學(xué)家發(fā)現(xiàn)過去功能一直不明確的一種細(xì)胞核內(nèi)RNA是形成核內(nèi)RNA—蛋白復(fù)合體的核心,，而后者在調(diào)節(jié)基因表達(dá)過程中發(fā)揮著重要作用。
公報(bào)說,，2002年曾有科學(xué)家報(bào)告說,，核內(nèi)RNA—蛋白復(fù)合體內(nèi)有2個(gè)能和RNA結(jié)合的控制蛋白，但科學(xué)家一直未能確認(rèn)與這兩個(gè)控制蛋白結(jié)合的RNA,。而產(chǎn)業(yè)技術(shù)綜合研究所的科學(xué)家在最新研究中發(fā)現(xiàn),，在核內(nèi)RNA—蛋白復(fù)合體中分布著一種非編碼的細(xì)胞核內(nèi)RNA，名為MENε/b RNA,，正是它和兩個(gè)控制蛋白產(chǎn)生結(jié)合,。
科學(xué)家使這種RNA分解，發(fā)現(xiàn)核內(nèi)RNA—蛋白復(fù)合體也隨之消失,。他們由此得出結(jié)論,，這種非編碼的細(xì)胞核內(nèi)RNA是核內(nèi)RNA—蛋白復(fù)合體形成的核心物質(zhì)。
公報(bào)說,，隨著基因組研究工作的推進(jìn),，科學(xué)家在人類和小鼠的細(xì)胞核內(nèi)找到了數(shù)量眾多且功能不明確的RNA。這些RNA引起了人們廣泛關(guān)注,。揭示這些RNA的功能將有助于新藥的研發(fā)工作,。（生物谷Bioon.com）
生物谷推薦原始出處：
PNAS Published online before print February 2, 2009, doi: 10.1073/pnas.0807899106
MENε/β noncoding RNAs are essential for structural integrity of nuclear paraspeckles
Yasnory T. F. Sasakia, Takashi Ideuea,b, Miho Sanoa,b, Toutai Mituyamac and Tetsuro Hirosea,1
aFunctional RNomics Team, Biomedicinal Information Research Center,
cRNA Informatics Team, Computational Biology Research Center, and
bJapan Biological Informatics Consortium, National Institute of Advanced Industrial Science and Technology, 2-42 Aomi, Koutou, Tokyo 135-0064, Japan
Abstract
Recent transcriptome analyses have shown that thousands of noncoding RNAs (ncRNAs) are transcribed from mammalian genomes. Although the number of functionally annotated ncRNAs is still limited, they are known to be frequently retained in the nucleus, where they coordinate regulatory networks of gene expression. Some subnuclear organelles or nuclear bodies include RNA species whose identity and structural roles are largely unknown. We identified 2 abundant overlapping ncRNAs, MENε and MENβ (MENε/β), which are transcribed from the corresponding site in the multiple endocrine neoplasia (MEN) I locus and which localize to nuclear paraspeckles. This finding raises the intriguing possibility that MENε/β are involved in paraspeckle organization, because paraspeckles are, reportedly, RNase-sensitive structures. Successful removal of MENε/β by a refined knockdown method resulted in paraspeckle disintegration. Furthermore, the reassembly of paraspeckles disassembled by transcriptional arrest appeared to be unsuccessful in the absence of MENε/β. RNA interference and immunoprecipitation further revealed that the paraspeckle proteins p54/nrb and PSF selectively associate with and stabilize the longer MENβ, thereby contributing to the organization of the paraspeckle structure. The paraspeckle protein PSP1 is not directly involved in either MENε/β stabilization or paraspeckle organization. We postulate a model for nuclear paraspeckle body organization where specific ncRNAs and RNA-binding proteins cooperate to maintain and, presumably, establish the structure.
