Protein
DNA-directed RNA polymerases IV and V subunit 2
Organism
Arabidopsis thaliana
Function
DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Second largest component of RNA polymerases IV and V which mediate short-interfering RNAs (siRNA) accumulation and subsequent RNA-directed DNA methylation-dependent (RdDM) transcriptional gene silencing (TGS) of endogenous repeated sequences, including transposable elements. Proposed to contribute to the polymerase catalytic activity and forms the polymerase active center together with the largest subunit. Also required for full erasure of methylation when the RNA trigger is withdrawn. Required for intercellular RNA interference (RNAi) leading to systemic post-transcriptional gene silencing. Involved in the maintenance of post-transcriptional RNA silencing. During interphase, mediates siRNA-independent heterochromatin association and methylation into chromocenters and condensation and cytosine methylation at pericentromeric major repeats. Required for complete maintenance of the 35S promoter homology-dependent TGS in transgenic plants and for the initial establishment of DNA methylation.
Similarity
Belongs to the RNA polymerase beta chain family.
Sequence
MPDMDIDVKDLEEFEATTGEINLSELGEGFLQSFCKKAATSFFDKYGLISHQLNSYNYFIEHGLQNVFQSFGEMLVEPSFDVVKKKDNDWRYATVKFGEVTVEKPTFFSDDKELEFLPWHARLQNMTYSARIKVNVQVEVFKNTVVKSDKFKTGQDNYVEKKILDVKKQDILIGSIPVMVKSILCKTSEKGKENCKKGDCAFDQGGYFVIKGAEKVFIAQEQMCTKRLWISNSPWTVSFRSENKRNRFIVRLSENEKAEDYKRREKVLTVYFLSTEIPVWLLFFALGVSSDKEAMDLIAFDGDDASITNSLIASIHVADAVCEAFRCGNNALTYVEQQIKSTKFPPAESVDECLHLYLFPGLQSLKKKARFLGYMVKCLLNSYAGKRKCENRDSFRNKRIELAGELLEREIRVHLAHARRKMTRAMQKHLSGDGDLKPIEHYLDASVITNGLSRAFSTGAWSHPFRKMERVSGVVANLGRANPLQTLIDLRRTRQQVLYTGKVGDARYPHPSHWGRVCFLSTPDGENCGLVKNMSLLGLVSTQSLESVVEKLFACGMEELMDDTCTPLFGKHKVLLNGDWVGLCADSESFVAELKSRRRQSELPREMEIKRDKDDNEVRIFTDAGRLLRPLLVVENLQKLKQEKPSQYPFDHLLDHGILELIGIEEEEDCNTAWGIKQLLKEPKIYTHCELDLSFLLGVSCAVVPFANHDHGRRVLYQSQKHCQQAIGFSSTNPNIRCDTLSQQLFYPQKPLFKTLASECLKKEVLFNGQNAIVAVNVHLGYNQEDSIVMNKASLERGMFRSEQIRSYKAEVDAKDSEKRKKMDELVQFGKTHSKIGKVDSLEDDGFPFIGANMSTGDIVIGRCTESGADHSIKLKHTERGIVQKVVLSSNDEGKNFAAVSLRQVRSPCLGDKFSSMHGQKGVLGYLEEQQNFPFTIQGIVPDIVINPHAFPSRQTPGQLLEAALSKGIACPIQKEGSSAAYTKLTRHATPFSTPGVTEITEQLHRAGFSRWGNERVYNGRSGEMMRSMIFMGPTFYQRLVHMSEDKVKFRNTGPVHPLTRQPVADRKRFGGIKFGEMERDCLIAHGASANLHERLFTLSDSSQMHICRKCKTYANVIERTPSSGRKIRGPYCRVCVSSDHVVRVYVPYGAKLLCQELFSMGITLNFDTKLC