End-filling of an oligonucleotide duplex containing an MDBP site in the human HSP70 promoter inhibits protein-DNA complex formation.
A site from the promoter region of the human hsp70 gene binds with a high affinity to the ubiquitous mammalian protein called methylated DNA-binding protein (MDBP) when it is present in a CpG-methylated oligonucleotide duplex with only 14 base-pairs. Binding to this site is dependent upon CpG methylation. Surprisingly, when the same methylated sequence is present in a duplex that has 22 or more base-pairs, binding to this protein is greatly inhibited. Such a requirement for a short duplex region is seen only in certain of the cytosine methylation-dependent binding sites for this protein and is proposed to reflect differences in the conformation of the duplex due to small differences in the nucleotide sequence.
Asiedu
C K
CK
Department of Biochemistry, Tulane Medical School, New Orleans, LA 70112.
Supakar
P C
PC
Ehrlich
M
M
D001483:Base Sequence; D001665:Binding Sites; D004247:DNA / Q000302:isolation & purification / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism*; D006360:Heat-Shock Proteins / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides / Q000138:chemical synthesis; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D014157:Transcription Factors
D004268:DNA-Binding Proteins; D006360:Heat-Shock Proteins; C066141:MBD1 protein, human; D009838:Oligodeoxyribonucleotides; D014157:Transcription Factors; D004247:DNA