title: A matrix protein silences transposons and repeats through interaction with retinoblastoma-associated proteins.
abstract: Epigenetic regulation helps to maintain genomic integrity by suppressing transposable elements (TEs) and also controls key developmental processes, such as flowering time. To prevent TEs from causing rearrangements and mutations, TE and TE-like repetitive DNA sequences are usually methylated, whereas histones are hypoacetylated and methylated on specific residues (e.g., H3 lysine 9 dimethylation [H3K9me2]). TEs and repeats can also attenuate gene expression. However, how various histone modifiers are recruited to target loci is not well understood. Here we show that knockdown of the nuclear matrix protein with AT-hook DNA binding motifs TRANSPOSABLE ELEMENT SILENCING VIA AT-HOOK (TEK) in Arabidopsis Landsberg erecta results in robust activation of various TEs, the TE-like repeat-containing floral repressor genes FLOWERING LOCUS C (FLC) and FWA. This derepression is associated with chromatin conformational changes, increased histone acetylation, reduced H3K9me2, and even TE transposition. TEK directly binds to an FLC-repressive regulatory region and the silencing repeats of FWA and associates with Arabidopsis homologs of the Retinoblastoma-associated protein 46/48, FVE and MSI5, which mediate histone deacetylation. We propose that the nuclear matrix protein TEK acts in the maintenance of genome integrity by silencing TE and repeat-containing genes.
authors: Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore 117604, Singapore.
authors: Yifeng
authors: Y
authors: Xu
authors: Yizhong
authors: Y
authors: Wang
authors: Hume
authors: H
authors: Stroud
authors: Xiaofeng
authors: X
authors: Gu
authors: Bo
authors: B
authors: Sun
authors: Eng-Seng
authors: ES
authors: Gan
authors: Kian-Hong
authors: KH
authors: Ng
authors: Steven E
authors: SE
authors: Jacobsen
authors: Yuehui
authors: Y
authors: He
authors: Toshiro
authors: T
authors: Ito
mesh_terms: D017360:Arabidopsis / Q000235:genetics*; D002843:Chromatin / Q000235:genetics / Q000378:metabolism; D019175:DNA Methylation; D004251:DNA Transposable Elements / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D044127:Epigenesis, Genetic; D018506:Gene Expression Regulation, Plant; D034521:Nuclear Matrix-Associated Proteins / Q000235:genetics*; D034622:RNA Interference; D034741:RNA, Small Interfering; D056286:Retinoblastoma Binding Proteins / Q000378:metabolism*
chemical_list: D002843:Chromatin; D004251:DNA Transposable Elements; D004268:DNA-Binding Proteins; D034521:Nuclear Matrix-Associated Proteins; D034741:RNA, Small Interfering; D056286:Retinoblastoma Binding Proteins