The human S mu bp-2, a DNA-binding protein specific to the single-stranded guanine-rich sequence related to the immunoglobulin mu chain switch region.
We have cloned the cDNA encoding the human homologue of S mu bp-2, which binds to single-stranded DNA with 5'-phosphorylated guanine-rich sequences related to the immunoglobulin mu chain switch (S mu) region. The deduced amino acid sequences of the mouse and human S mu bp-2 are 76.5% homologous and contain motifs conserved among helicases. We have identified a domain essential for DNA binding at residues 638-786. The binding domain is less conserved (63% homologous) than the putative catalytic domain of N-terminal half containing most of the helicase motifs (85% homologous). The human and mouse S mu bp-2 have similar, although slightly different, binding specificities. Although the mouse S mu bp-2 preferentially binds to the mouse S mu motif (GGGGT), the human S mu bp-2 binds equally well to the human (GGGCT) and mouse S mu motifs. The human S mu bp-2 gene was mapped to chromosome 11 q13.2-q13.4 by in situ hybridization.
Fukita
Y
Y
Department of Medical Chemistry, Kyoto University Faculty of Medicine, Japan.
Mizuta
T R
TR
Shirozu
M
M
Ozawa
K
K
Shimizu
A
A
Honjo
T
T
D000595:Amino Acid Sequence; D000818:Animals; D001482:Base Composition; D001483:Base Sequence; D002460:Cell Line; D002880:Chromosomes, Human, Pair 11; D004247:DNA / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D006147:Guanine / Q000378:metabolism; D006801:Humans; D007075:Immunoglobulin M / Q000235:genetics*; D007134:Immunoglobulin Switch Region / Q000235:genetics*; D017403:In Situ Hybridization; D051379:Mice; D008969:Molecular Sequence Data; D015183:Restriction Mapping; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors
D004268:DNA-Binding Proteins; C489892:IGHMBP2 protein, human; C081225:Ighmbp2 protein, mouse; D007075:Immunoglobulin M; D014157:Transcription Factors; D006147:Guanine; D004247:DNA