A DNA Methyltransferase Homolog With a Chromodomain Exists in Multiple Polymorphic Forms in Arabidopsis

Chromodomains are thought to mediate protein-protein interactions between chromatin components. We have detected a chromodomain embedded within the catalytic region of a predicted Arabidopsis DNA methyltransferase that is diverged from other eukaryotic enzymes. The 791 residue “chromomethylase” (CMT1) is encoded by a floral transcript that is spliced from 20 exons and is present at only ~1/10−7 of total mRNA. Genomic sequencing reveals an...