Figure 1

Nematode MBD-2 proteins lack the methyl-binding-domain. A. Amino-terminal sequence of the H. sapiens MBD-2 protein showing the methyl-binding domain (red box) and the conserved MBD2/3 motif (blue box). Critical residues interacting with methylated DNA are highlighted in red. The secondary structure of the methyl-binding-domain is shown below the sequence. Beta-strands 1–4 (β1–4), alpha helix 1 (α1), loops 1 and 2 (L1,2). B. Schematic alignment showing the MBD2 and MBD3 proteins from mouse (Mus musculus), the two isoforms of Drosophila melanogaster MBD2/3, P. pacificus and C. elegans MBD-2. Color codes refer to the methyl-binding-domain (red), the MBD2/3 SIFPQ conserved motif (blue), coiled-coil domain (orange) and an E-rich patch (pink) found only in MBD3. C. Amino acid alignment of the amino-terminal part of the MBD-2 proteins from Brugia malayi (Bm), Haemochus contortus (Hc), Onchocerca volvulus (Ov), Meloidogyne hapla (Mh) and Nippostrongylus brasiliensis (Nb), Pristionchus pacificus (Ppa), Caenorhabditis elegans (Cel) and Caenorhabditis briggsae (Cbr). The MBD2/3 conserved motif, SIFPQ, of D. melanogaster, Apis mellifera, Danio rerio and Homo sapiens MBD2/3 proteins is highly conserved in the nematode homologues except for M. hapla and the Caenorhabditis species.