Structural highlightsFunctionNRPE1_ARATH DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Largest and catalytic component of RNA polymerase V involved in RNA-directed DNA methylation-dependent (RdDM) silencing of endogenous repeated sequences, including transposable elements. Also required for full erasure of methylation when the RNA trigger is withdrawn. Seems also involved in the synthesis of short-interfering RNAs (siRNA). Essential component of a self-reinforcing loop coupling de novo DNA methylation to siRNA production. Involved in the maintenance of post-transcriptional RNA silencing.[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12]
Publication Abstract from PubMed
De novo DNA methylation in plants relies on transcription of RNA polymerase V (Pol V) along with KTF1, which produce long non-coding RNAs for recruitment and assembly of the DNA methylation machinery. Here, we report a cryo-EM structure of the Pol V transcription elongation complex bound to KTF1. The structure reveals the conformation of the structural motifs in the active site of Pol V that accounts for its inferior RNA-extension ability. The structure also reveals structural features of Pol V that prevent it from interacting with the transcription factors of Pol II and Pol IV. The KOW5 domain of KTF1 binds near the RNA exit channel of Pol V providing a scaffold for the proposed recruitment of Argonaute proteins to initiate the assembly of the DNA methylation machinery. The structure provides insight into the Pol V transcription elongation process and the role of KTF1 during Pol V transcription-coupled DNA methylation.
A cryo-EM structure of KTF1-bound polymerase V transcription elongation complex.,Zhang HW, Huang K, Gu ZX, Wu XX, Wang JW, Zhang Y Nat Commun. 2023 May 30;14(1):3118. doi: 10.1038/s41467-023-38619-x. PMID:37253723[13]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See AlsoReferences
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- ↑ Zhang HW, Huang K, Gu ZX, Wu XX, Wang JW, Zhang Y. A cryo-EM structure of KTF1-bound polymerase V transcription elongation complex. Nat Commun. 2023 May 30;14(1):3118. PMID:37253723 doi:10.1038/s41467-023-38619-x
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