ZBED6, a novel transcription factor derived from a domesticated DNA transposon regulates IGF2 expression and muscle growth.
ZBED6, a novel transcription factor derived from a domesticated DNA transposon regulates IGF2 expression and muscle growth.
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DOI：
10.1371/journal.pbio.1000256
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发表时间：
2009-12
期刊：
影响因子：
9.8
通讯作者：
Andersson L
中科院分区：
文献类型：
--
作者：
Markljung E;Jiang L;Jaffe JD;Mikkelsen TS;Wallerman O;Larhammar M;Zhang X;Wang L;Saenz-Vash V;Gnirke A;Lindroth AM;Barrés R;Yan J;Strömberg S;De S;Pontén F;Lander ES;Carr SA;Zierath JR;Kullander K;Wadelius C;Lindblad-Toh K;Andersson G;Hjälm G;Andersson L
这项研究确定了一种以前未知的蛋白质，由一种驯化的DNA转座子编码，称为ZBED6，它调节胰岛素样生长因子2（IGF2）基因的表达，可能还有许多其他基因，在所有胎盘哺乳动物中，包括人类。猪IGF2内含子3的单核苷酸取代消除了阻遏物的结合位点，导致骨骼肌中IGF2上调3倍。这种突变对肌肉生长、心脏大小和脂肪沉积有重大影响。在这里，我们已经确定了阻遏物，并发现命名为ZBED6的蛋白质是以前未知的，对胎盘哺乳动物具有特异性，并且来自一个exapted DNA转座子。小鼠C2C12成肌细胞中Zbed6的沉默影响Igf2表达、细胞增殖、伤口愈合和肌管形成。使用C2C12细胞的染色质免疫沉淀（ChIP）测序在基因组中鉴定了约2，500个ZBED6结合位点，并且推断的共有基序与Igf2中已建立的结合位点完美匹配。与ZBED6结合位点相关的基因在某些基因本体分类中显示出高度显著的富集，包括发育和转录调控。在突变猪和ZBED6沉默的C2C12成肌细胞中的表型效应、极端序列保守性、其核仁定位、广泛的组织分布以及具有基本生物学功能的许多靶基因表明，ZBED6是胎盘哺乳动物中重要的转录因子，影响发育、细胞增殖和生长。影响复杂性状和病症的基因和突变的分子鉴定已被证明在人类以及模式生物中非常具有挑战性。这些所谓的数量性状来自两个或多个基因与其环境之间的相互作用，并且可以通过称为数量性状基因座（QTL）的紧密连锁的DNA片段映射到其潜在基因。以前，我们确定了一个单核苷酸取代在非编码区的胰岛素样生长因子2基因（IGF2）在猪是潜在的一个主要QTL影响肌肉生长，心脏大小和脂肪沉积。该突变破坏了与作为IGF2转录阻遏物的未知核蛋白的相互作用。在本研究中，我们已经分离出一个未知功能的锌指蛋白，并表明它调节IGF2的表达。我们命名为ZBED6的蛋白质由一个驯化的DNA转座子编码，该转座子在胎盘哺乳动物辐射之前插入基因组中。ZBED6是胎盘哺乳动物特有的，在物种间高度保守。我们对ZBED6的功能表征表明，它具有广泛的组织分布，并且可能影响除IGF2之外的数千种控制基本生物过程的其他基因的表达。我们假设ZBED6是一个重要的转录因子，影响胎盘哺乳动物的发育，细胞增殖和生长。
This study identifies a previously uncharacterized protein, encoded by a domesticated DNA transposon, called ZBED6 that regulates the expression of the insulin-like growth factor 2 (IGF2) gene, and possibly numerous others, in all placental mammals including human. A single nucleotide substitution in intron 3 of IGF2 in pigs abrogates a binding site for a repressor and leads to a 3-fold up-regulation of IGF2 in skeletal muscle. The mutation has major effects on muscle growth, size of the heart, and fat deposition. Here, we have identified the repressor and find that the protein, named ZBED6, is previously unknown, specific for placental mammals, and derived from an exapted DNA transposon. Silencing of Zbed6 in mouse C2C12 myoblasts affected Igf2 expression, cell proliferation, wound healing, and myotube formation. Chromatin immunoprecipitation (ChIP) sequencing using C2C12 cells identified about 2,500 ZBED6 binding sites in the genome, and the deduced consensus motif gave a perfect match with the established binding site in Igf2. Genes associated with ZBED6 binding sites showed a highly significant enrichment for certain Gene Ontology classifications, including development and transcriptional regulation. The phenotypic effects in mutant pigs and ZBED6-silenced C2C12 myoblasts, the extreme sequence conservation, its nucleolar localization, the broad tissue distribution, and the many target genes with essential biological functions suggest that ZBED6 is an important transcription factor in placental mammals, affecting development, cell proliferation, and growth. The molecular identification of genes and mutations affecting complex traits and disorders has proven to be very challenging in humans as well as in model organisms. These so-called quantitative traits arise from interactions between two or more genes and their environment, and can be mapped to their underlying genes via closely linked stretches of DNA called quantitative trait loci (QTL). Previously, we identified a single nucleotide substitution in a noncoding region of the insulin-like growth factor 2 gene (IGF2) in pigs that is underlying a major QTL affecting muscle growth, heart size, and fat deposition. The mutation disrupts interaction with an unknown nuclear protein acting as a repressor of IGF2 transcription. In the present study, we have isolated a zinc finger protein of unknown function and show that it regulates the expression of IGF2. The protein, which we named ZBED6, is encoded by a domesticated DNA transposon that was inserted into the genome prior to the radiation of placental mammals. ZBED6 is exclusive to placental mammals and highly conserved among species. Our functional characterization of ZBED6 shows that it has a broad tissue distribution and may affect the expression of thousands of other genes, besides IGF2, that control fundamental biological processes. We postulate that ZBED6 is an important transcription factor affecting development, cell proliferation, and growth in placental mammals.
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影响因子：
14.8
作者：
Ong, Shao-En;Mann, Matthias
通讯作者：
Mann, Matthias
DOI：
10.1073/pnas.1532175100
发表时间：
2003-07-08
影响因子：
11.1
作者：
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通讯作者：
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影响因子：
4.4
作者：
Braunschweig, MH;Van Laere, AS;Andersson, G
通讯作者：
Andersson, G
影响因子：
3.1
作者：
Wang, YH;Chen, YH;Tsai, HJ
通讯作者：
Tsai, HJ
影响因子：
64.8
作者：
Van Laere, AS;Nguyen, M;Andersson, L
通讯作者：
Andersson, L