The role of RNA Polymerase V in RNA-directed DNA methylation

RNA 聚合酶 V 在 RNA 指导的 DNA 甲基化中的作用

基本信息

批准号：
8516534
负责人：
Ross Roland Cocklin
金额：
$ 5.39万
依托单位：
KEENE STATE COLLEGE
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-08-15 至 2014-11-14
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8516534
关键词：
Accounting Address Affinity Chromatography Amino Acid Sequence Arabidopsis Binding C-terminal Chromatin Chromatin Structure Collaborations Consensus Sequence Cytosine DNA DNA Methylation DNA Methyltransferase DNA Modification Methylases DNA Polymerase I DNA Polymerase II DNA Sequence DNA Transposable Elements DNA-Directed RNA Polymerase DRD1 gene Data Development Double-Stranded RNA Enzymes Epigenetic Process Eukaryota Fellowship Fission Yeast Fragile X Syndrome Functional RNA Gene Expression Regulation Gene Silencing Genes Genetic Transcription Genome Genomics Goals Heterochromatin Histones Human In Vitro Intercistronic Region Malignant Neoplasms Mass Spectrum Analysis Mediating Methylation Modeling Mouse-ear Cress Names Nucleotides Pathway interactions Plants Play Polymerase Process Protein Family Proteins Publications RNA RNA Polymerase I RNA Polymerase II RNA-Directed RNA Polymerase Recruitment Activity Ribonuclease III Role SWI2/SNF2 Site Small Interfering RNA Specificity System Tertiary Protein Structure Testing Transcript Work chromatin modification chromatin remodeling cis acting element cohesin condensin feeding fly genome sequencing genome-wide human DICER1 protein human disease promoter protein protein interaction reconstitution research study

项目摘要

DESCRIPTION (provided by applicant): Prior to publication of the Arabidopsis thaliana genome sequence in the year 2000, there were three known eukaryotic, multisubunit RNA Polymerases, abbreviated as Pol I, II and III. The Arabidopsis genome sequence revealed that plants have two additional RNA Polymerases, named Pol IV and V. Affinity purification and protein identification by mass spectrometry revealed that Pol IV and Pol V evolved as specialized forms of RNA Polymerase II, with six of the twelve subunits of Pol II, IV and V encoded by the same genes. Pol IV and Pol V have independent and essential roles in a pathway that ultimately contributes to proper plant morphological development, large scale heterochromatin organization and the silencing of transposable elements and other repeats. Pol IV, in collaboration with the RNA Dependent RNA Polymerase RDR2 and the Dicer-Like protein DCL3, is required to produce small interfering RNAs that interact with non-coding transcripts generated by Pol V to recruit DNA methylating and histone modifying enzymes to the adjacent chromatin. This epigenetic remodeling inhibits localized transcription by RNA Polymerases I, II and III. Three subunits differ between Pol IV and Pol V and presumably account for their unique functions. There are approximately ~6000 sites in the Arabidopsis genome that are subject to Pol IV and Pol V cytosine methylation; however, we know of very few DNA sequences bound by either Pol IV or Pol V. It is not clear whether specific DNA sequences are primarily responsible for recruiting Pol IV and Pol V to DNA or whether chromatin structure plays a primary role. It is also unclear how Pol IV and Pol V activities are coordinated with other activities within the RNA-directed DNA methylation pathway. During this fellowship period, my goal is to address many of these questions by defining the genome-wide targets of Pol V and the transcripts it produces. Furthermore, I will seek to understand the mechanism by which the Pol V polymerase selects its targets. I will also attempt to define the proteins that interact with Pol V so that we have a clearer picture of how Pol V remodels chromatin and silences genes.

描述（由申请人提供）：在2000年发布拟南芥基因组序列之前，有三种已知的真核生物，多生RNA RNA聚合酶，缩写为Pol I，II，II和III。拟南芥基因组序列表明，植物具有两个额外的RNA聚合酶，命名为Pol IV和V。通过质谱法的亲和力纯化和蛋白质鉴定表明，Pol IV和Pol v演变为RNA聚合酶II的专用形式，其中六个是十二个亚基的六个亚基。 Pol II，IV和V由相同基因编码。 Pol IV和Pol V在途径中具有独立和重要的作用，该途径最终有助于植物形态发展，大规模异染色质组织以及迁移元素和其他重复序列的沉默。 POL IV与RNA依赖性RNA聚合酶RDR2和类dicer样蛋白DCL3合作，需要产生与POL V相互作用的小型干扰RNA，以募集DNA甲基化和组蛋白将酶修改为相邻染色剂，以募集DNA甲基化和组蛋白。。这种表观遗传重塑抑制了RNA聚合酶I，II和III的局部转录。 Pol IV和Pol V之间的三个亚基不同，大概是其独特功能的解释。拟南芥基因组中大约有〜6000个位点，这些位点受Pol IV和pol V胞嘧啶甲基化的影响。但是，我们知道很少有由POL IV或POL V结合的DNA序列。目前尚不清楚特定的DNA序列是否主要负责募集Pol IV和Pol V到DNA中，或者染色质结构是否起主要作用。还不清楚在RNA指导的DNA甲基化途径中如何与Pol IV和Pol V活性与其他活性进行协调。在这个研究金期间，我的目标是通过定义Pol V的全基因组目标及其产生的成绩单来解决许多此类问题。此外，我将寻求了解POL V聚合酶选择其靶标的机制。我还将尝试定义与Pol V相互作用的蛋白质，以便更清楚地了解Pol V如何重塑染色质和沉默基因。