The regulatory region of the human desmocollin 3 promoter forms a DNA four-way junction.
Adhesion between desmosomal junctions is mediated by structural proteins of the cadherin family, viz. three desmocollins (DSC) and three desmogleins (DSG). Promoter and primer extension analysis of human DSC3 showed a TATA-less sequence initiating transcription via a cluster of sites upstream of the coding region. Deletion analysis of 1 kb of the promoter showed that expression is regulated between --303 and --203 bp upstream of the start-site of translation. Tertiary structure analysis of this cis-active region (cis 1) revealed a potential DNA 4-way junction which is notably G/C-rich in sequence. PAGE analysis of this region identified four differently migrating forms of the DNA. Structure-specific cleavage of the DNA with bacteriophage T7 endonuclease I showed the slowest migrating form to be either an extended/cruciform or stacked-X 4-way junction. DNA-binding, gel retardation assays of the cis 1 region showed distinct DNA-protein complexes and by competition experiments and using purified junction DNA we show that one of these complexes bound with both sequence and structure specificity to the 4-way junction DNA.
Gadhavi
P L
PL
Division of Membrane Biology, National Institute for Medical Research, Mill Hill, London NW7 1AA, United Kingdom.
Greenwood
M D
MD
Strom
M
M
King
I A
IA
Buxton
R S
RS
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D002478:Cells, Cultured; D003001:Cloning, Molecular; D004247:DNA / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D003850:Deoxyribonuclease I / Q000378:metabolism; D051187:Desmocollins; D006801:Humans; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000235:genetics*; D051379:Mice; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017384:Sequence Deletion; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured
C490356:DSC3 protein, human; D051187:Desmocollins; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; C090171:Dsc3 protein, mouse; D004247:DNA; D008156:Luciferases; D003850:Deoxyribonuclease I