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A cryo-EM structure of KTF1-bound polymerase V transcription elongation complex.

ABSTRACT: 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.

SUBMITTER: Zhang HW

PROVIDER: S-EPMC10229537 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

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A cryo-EM structure of KTF1-bound polymerase V transcription elongation complex.

Zhang Hong-Wei HW Huang Kun K Gu Zhan-Xi ZX Wu Xiao-Xian XX Wang Jia-Wei JW Zhang Yu Y

Nature communications 20230530 1

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 ...[more]

PMID: 37253723

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