CLSY docking to Pol IV requires a conserved domain critical for small RNA biogenesis and transposon silencing
Year: 2024
Type: article
Abstract: Eukaryotes must balance the need for gene transcription by RNA polymerase II (Pol II) against the danger of mutations caused by transposable element (TE) proliferation. In plants, these gene expression and TE silencing activities are divided between different RNA polymerases. Specifically, RNA polymerase IV (Pol IV), which evolved from Pol II, transcribes TEs to generate small interfering RNAs (siRNAs) that guide DNA methylation and block TE transcription by Pol II. While the Pol IV complex is recruited to TEs via SNF2-like CLASSY (CLSY) proteins, how Pol IV partners with the CLSYs remains unknown. Here, we identified a conserved CYC-YPMF motif that is specific to Pol IV and is positioned on the complex exterior. Furthermore, we found that this motif is essential for the co-purification of all four CLSYs with Pol IV, but that only one CLSY is present in any given Pol IV complex. These findings support a "one CLSY per Pol IV" model where the CYC-YPMF motif acts as a CLSY-docking site. Indeed, mutations in and around this motif phenocopy pol iv null and clsy quadruple mutants. Together, these findings provide structural and functional insights into a critical protein feature that distinguishes Pol IV from other RNA polymerases, allowing it to promote genome stability by targeting TEs for silencing.
Source: Nature Communications
Institutions: Centre National de la Recherche Scientifique, Institut de Biologie Moléculaire des Plantes, Université de Strasbourg, Salk Institute for Biological Studies, Zhejiang University, Institut de Biologie Moléculaire et Cellulaire, University of California, Los Angeles, University of Basel, University of California San Diego
Language: English
Subfield: Plant Science
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $6,790
Funders: National Science Foundation, U.S. Department of Health and Human Services, Leona M. and Harry B. Helmsley Charitable Trust, Agence Nationale de la Recherche, Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, Université de Strasbourg, National Institutes of Health, National Institute on Aging, National Cancer Institute, National Institute of General Medical Sciences
Awards: G1190173965, G164444715, G1800105685, Par-delà les frontières, l'Université de Strasbourg, G2308104247, San Diego Nathan Shock Center, G2659019386, G2694206344, Façonner les talents en formation et en recherche à l'Université de Strasbourg, G2980570810, G3921339131, G4410396829, Integrative Molecular and Cellular Biology, G471331628, G4779185514, G5296751580, Epigenetic and biochemical determinants of nuclear siRNA biogenesis in Arabidopsis, Evolution of mitochondria molecular architecture across the photosynthetic tree of life, Establishment and Modulation of DNA Methylation Patterns in Arabidopsis, G6803667113, G6901549817, G6954794388, G7240651115, Proteolytic Control of Iron Metabolism by the E3 Ubiquitin Ligase FBXL5
OpenAlex ID: W4404790842