Sequence-specific DNA-binding of evolutionary divergent KRAB-zinc finger proteins

进化趋异的 KRAB-锌指蛋白的序列特异性 DNA 结合

• 批准号: 8324743
• 负责人: Adam Michael Blattler
• 金额: $ 3.3万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-21 至 2014-07-20
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8324743
• 关键词: Binding; Binding Sites; Biochemical; Biological Assay; Boxing; C2H2 Zinc Finger; Categories; ChIP-seq; Chromatin; Chromosomes; Chromosomes, Human, Pair 19; Chromosomes, Human, Pair 7; Communities; Complex; DNA Binding; DNA Binding Domain; Data; Development; Evolution; Family; Gene Cluster; Gene Expression; Gene Targeting; Genes; Genomics; Goals; Health; Human; Human Chromosomes; In Vitro; Malignant Neoplasms; Mammals; Mediating; Modeling; Mus; Oligonucleotides; Ontology; Phylogenetic Analysis; Physiological; Proteins; Recruitment Activity; Repression; Research; Role; Testing; Tissues; Transcription Repressor/Corepressor; Zinc Fingers; chromatin immunoprecipitation; design; human BRAF protein; human ZNF45 protein; in vivo; knock-down; public health relevance

DESCRIPTION (provided by applicant): KRAB domain-containing zinc finger proteins (KRAB-ZNFs) are a large, but poorly characterized family of transcriptional regulators in mammals. KRAB-ZNFs are thought to function as transcriptional repressors through a KRAB box-mediated interaction with the KAP1 corepressor complex. Despite much biochemical evidence, there are very few known target genes of KRAB-ZNFs and the physiological roles of these regulators remain essentially unknown. The genes encoding zinc finger proteins are typically found in clusters located on several different chromosomes. These clusters are thought to have arisen from tandem duplications and are present in much higher numbers in mammalian species. Recent phylogenetic analysis suggests that the KRAB ZNF gene clusters on human chromosome 19 and mouse chromosome 7 are highly related; it appears that a single mouse gene Zfp61 has given rise to a cluster of 10 human genes on chromosome 19. Each of these genes contains a KRAB transcriptional repressor domain and has varying numbers of C2H2 zinc finger DNA binding domains. Such lineage specific duplications of KRAB-ZNFs may have important implications for defining species-specific transcriptional networks and may have significant implications on development. I propose that the evolution of human specific KRAB-ZNF genes has a significant impact on lineage-specific transcriptional networks. Specifically, the divergence within the C2H2 regions of the cluster of KRAB-ZNF genes leads to diverse DNA binding activities of the 10 KRAB-ZNF transcriptional repressors. These separate factors are therefore capable of regulating 10 distinct subsets of genes that are otherwise only controlled by a single transcription repressor in mouse. I will express tagged versions of the 10 human genes and one mouse gene and analyze their targets using an in vivo chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq). PUBLIC HEALTH RELEVANCE: This proposal aims to study a group of poorly characterized zinc finger proteins, which are likely to be involved in regulating tissue- or species-specific transcriptional networks. Cancers have been shown to contain altered copy numbers and expression levels of zinc finger proteins structurally related to those in this study. Ultimately, this research will add to the community's understanding of the potential impact of the gain, loss, and misregulation of KRAB-ZNF genes on human health.

描述（由申请人提供）：含KRAB结构域的锌指蛋白（KRAB-ZNF）是哺乳动物中转录调节因子的一个大家族，但特征不明显。KRAB-ZNF被认为是通过KRAB盒介导的与KAP 1辅阻遏物复合物的相互作用而起转录阻遏物的作用。尽管有很多生化证据，但KRAB-ZNF的已知靶基因很少，这些调节因子的生理作用基本上仍然未知。编码锌指蛋白的基因通常在位于几个不同染色体上的簇中发现。这些簇被认为是由串联复制产生的，并且在哺乳动物物种中以更高的数量存在。最近的系统发育分析表明，人类19号染色体和小鼠7号染色体上的KRAB ZNF基因簇高度相关;似乎单个小鼠基因Zfp 61已经引起了19号染色体上的10个人类基因的簇。这些基因中的每一个都含有KRAB转录阻遏物结构域，并且具有不同数量的C2 H2锌指DNA结合结构域。KRAB-ZNF的这种谱系特异性重复可能对定义物种特异性转录网络具有重要意义，并且可能对发育具有重要意义。我认为人类特异性KRAB-ZNF基因的进化对谱系特异性转录网络有显著影响。具体而言，KRAB-ZNF基因簇的C2 H2区域内的差异导致10种KRAB-ZNF转录抑制子的不同DNA结合活性。因此，这些独立的因子能够调节10个不同的基因亚群，否则这些基因在小鼠中仅由单个转录阻遏物控制。我将表达10个人类基因和一个小鼠基因的标记版本，并使用体内染色质免疫沉淀法分析它们的靶标，然后进行高通量测序（ChIP-seq）。 公共卫生相关性：该建议旨在研究一组特征不明显的锌指蛋白，这些蛋白可能参与调节组织或物种特异性转录网络。癌症已被证明含有改变的拷贝数和表达水平的锌指蛋白的结构相关的那些在这项研究中。最终，这项研究将增加社区对KRAB-ZNF基因的获得，损失和失调对人类健康的潜在影响的理解。