Unknown,Transcriptomics,Genomics,Proteomics

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Characterization of small RNA-generating regions targeted by RNA polymerase V in Arabidopsis

ABSTRACT: In plants, heterochromatin is maintained by a small RNA-based gene silencing mechanism known as RNA-directed DNA methylation (RdDM). RdDM requires the non-redundant functions of two plant-specific DNA-dependent RNA polymerases (Pol) Pol IV and Pol V. Pol IV plays a major role in siRNA biogenesis, while Pol V may recruit DNA methylation machinery to target endogenous loci for silencing. Although small RNA-generating regions which are dependent on both Pol IV and Pol V have been identified previously, the genomic loci targeted Pol V for siRNA accumulation and silencing have not been described extensively. To characterize the Pol V-dependent, heterochromatic siRNA-generating regions in the Arabidopsis genome, we deeply sequenced the small RNA populations of wild-type and Pol V mutant plants. Furthermore, we characterized the siRNA-generating regions which were dependent on RdDM effectors and examined their dependency on Pol V. Small RNA libraries were generated and deeply sequenced from mutant alleles dms4-1, drd1-1, dms3-1, and rdm1-4, along with their control library (“Wt(T+S)”) which has been described previously (Kanno et al. 2004 Current Biology). More than 2,000 small RNA-generating loci were identified which were greatly suppressed in Pol V mutants. The Pol V-dependent, heterochromatic siRNA-generating regions were characterized in the Arabidopsis genome by deep sequencing the small RNA populations of wild-type and Pol V mutant plants. Deep SBS sequencing was used for small RNA profiling of immature inflorescence tissues from RNA polymerase V and RdDM mutants.

ORGANISM(S): Arabidopsis thaliana

SUBMITTER: Blake Meyers

PROVIDER: E-GEOD-36424 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

RNA polymerase V-dependent small RNAs in Arabidopsis originate from small, intergenic loci including most SINE repeats.

Lee Tzuu-fen TF Gurazada Sai Guna Ranjan SG Zhai Jixian J Li Shengben S Simon Stacey A SA Matzke Marjori A MA Chen Xuemei X Meyers Blake C BC

Epigenetics 20120701 7

In plants, heterochromatin is maintained by a small RNA-based gene silencing mechanism known as RNA-directed DNA methylation (RdDM). RdDM requires the non-redundant functions of two plant-specific DNA-dependent RNA polymerases (RNAP), RNAP IV and RNAP V. RNAP IV plays a major role in siRNA biogenesis, while RNAP V may recruit DNA methylation machinery to target endogenous loci for silencing. Although small RNA-generating regions that are dependent on both RNAP IV and RNAP V have been identified ...[more]

PMID: 22647529

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Dataset Information

Characterization of small RNA-generating regions targeted by RNA polymerase V in Arabidopsis

Publications

RNA polymerase V-dependent small RNAs in Arabidopsis originate from small, intergenic loci including most SINE repeats.

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