The nuclear 42-kDa phosphoprotein preferentially binds promoter-containing single-stranded DNA.
The DNA-binding activity of a 42-kDa phosphoprotein from salivary gland cells and cultured epithelial cells of Chironomus tentans have been analyzed by the Southwestern technique. Both the salivary gland and the epithelial cell 42-kDa polypeptides were found to be single-stranded DNA-binding proteins. They bind to single-stranded promoter-containing restriction fragments including sequences from -204 to +74 from the ecdysterone controlled I-18C gene as well as sequences including the joint histone H2A/H2B promoters in a sequence selective manner. By contrast, the 42-kDa polypeptides show no significant binding to intragenic restriction fragments from +71 to +351 from the I-18C gene. Previous and present data taken together suggest that the 42-kDa protein has a general role in the regulation of protein coding genes.
Stigare
J
J
Department of Medical Cell Biology, Karolinska Institutet, Stockholm, Sweden.
Egyhazi
E
E
D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism*; D002478:Cells, Cultured; D002683:Chironomidae; D015342:DNA Probes; D004277:DNA, Single-Stranded / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism*; D004848:Epithelium / Q000378:metabolism; D015151:Immunoblotting; D008970:Molecular Weight; D009687:Nuclear Proteins / Q000302:isolation & purification / Q000378:metabolism*; D010750:Phosphoproteins / Q000302:isolation & purification / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D012469:Salivary Glands / Q000378:metabolism*
D015342:DNA Probes; D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins