An alternative polyadenylation mechanism coopted to the Arabidopsis RPP7 gene through intronic retrotransposon domestication.
Transposable elements (TEs) can drive evolution by creating genetic and epigenetic variation. Although examples of adaptive TE insertions are accumulating, proof that epigenetic information carried by such "domesticated" TEs has been coopted to control host gene function is still limited. We show that COPIA-R7, a TE inserted into the Arabidopsis thaliana disease resistance gene RPP7 recruited the histone mark H3K9me2 to this locus. H3K9me2 levels at COPIA-R7 affect the choice between two alternative RPP7 polyadenylation sites in the pre-mRNA and, thereby, influence the critical balance between RPP7-coding and non-RPP7-coding transcript isoforms. Function of RPP7 is fully dependent on high levels of H3K9me2 at COPIA-R7. We present a direct in vivo demonstration for cooption of a TE-associated histone mark to the epigenetic control of pre-mRNA processing and establish a unique mechanism for regulation of plant immune surveillance gene expression. Our results functionally link a histone mark to alternative polyadenylation and the balance between distinct transcript isoforms from a single gene.
Center for Plant Cell Biology, Institute for Integrative Genome Biology, Department of Botany and Plant Sciences, University of California, Riverside, CA 92521.
Tokuji
T
Tsuchiya
Thomas
T
Eulgem
D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D044127:Epigenesis, Genetic; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D000076983:Histone Methyltransferases; D011495:Histone-Lysine N-Methyltransferase / Q000235:genetics / Q000378:metabolism; D006657:Histones / Q000378:metabolism; D007438:Introns; D008969:Molecular Sequence Data; D030821:Plants, Genetically Modified; D026723:Polyadenylation; D012322:RNA Precursors / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D018626:Retroelements / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
D029681:Arabidopsis Proteins; C523205:EDM2 protein, Arabidopsis; D006657:Histones; D012322:RNA Precursors; D018749:RNA, Plant; C523204:RPP7 protein, Arabidopsis; D018626:Retroelements; D014157:Transcription Factors; D000076983:Histone Methyltransferases; D011495:Histone-Lysine N-Methyltransferase
EDM2; Hyaloperonospora arabidopsidis; PHD finger; post translational histone modification