Publication Date:
2009-03-03
Description:
Plants have distinct RNA polymerase complexes (Pol IV and Pol V) with largely unknown roles in maintaining small RNA-associated gene silencing. Curiously, the eudicot Arabidopsis thaliana is not affected when either function is lost. By use of mutation selection and positional cloning, we showed that the largest subunit of the presumed maize Pol IV is involved in paramutation, an inherited epigenetic change facilitated by an interaction between two alleles, as well as normal maize development. Bioinformatics analyses and nuclear run-on transcription assays indicate that Pol IV does not engage in the efficient RNA synthesis typical of the three major eukaryotic DNA-dependent RNA polymerases. These results indicate that Pol IV employs abnormal RNA polymerase activities to achieve genome-wide silencing and that its absence affects both maize development and heritable epigenetic changes.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Erhard, Karl F Jr -- Stonaker, Jennifer L -- Parkinson, Susan E -- Lim, Jana P -- Hale, Christopher J -- Hollick, Jay B -- New York, N.Y. -- Science. 2009 Feb 27;323(5918):1201-5. doi: 10.1126/science.1164508.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Plant and Microbial Biology, 111 Koshland Hall, University of California, Berkeley, CA 94720-3102, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19251626" target="_blank"〉PubMed〈/a〉
Keywords:
Alleles
;
Amino Acid Sequence
;
Base Sequence
;
Computational Biology
;
DNA-Directed RNA Polymerases/chemistry/genetics/*metabolism
;
*Epigenesis, Genetic
;
Gene Silencing
;
Genes, Plant
;
Molecular Sequence Data
;
*Mutation
;
Phylogeny
;
Protein Subunits/chemistry/genetics/metabolism
;
RNA, Plant/genetics/metabolism
;
RNA, Small Interfering/genetics/metabolism
;
Transcription, Genetic
;
Zea mays/*enzymology/*genetics/growth & development
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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