Molecular cloning of ID4, a novel dominant negative helix-loop-helix human gene on chromosome 6p21.3-p22.
Transcription factors containing a basic helix-loop-helix (bHLH) motif regulate the expression of tissue-specific genes in a number of mammalian and insect systems. DNA-binding activity of the bHLH proteins is dependent upon formation of homo- and/or heterodimers. Dominant negative HLH proteins (Id-related genes) also contain the HLH-dimerization domain but lack the DNA-binding basic domain. Consequently, Id proteins inhibit binding to DNA and transcriptional transactivation by heterodimerization with bHLH proteins. We report here the cDNA sequence of a novel human HLH gene (HGMW-approved symbol ID4) that lacks the basic domain. ID4 is differentially expressed in adult organs in four mRNA molecules, which are presumably a result of differential splicing and/or alternative usage of the polyadenylation sites. Transfection experiments indicated that enforced expression of Id-4H protein inhibits the trans-activation of the muscle creatine kinase E-box enhancer by MyoD. Finally, we localized the ID4 gene to the chromosome 6p21-p22 region.
Pagliuca
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A
Dipartimento di Genetica, Biologia Generale e Molecolare, Università Federico II, Via Mezzocannone 8, Naples, Italy.
Bartoli
P C
PC
Saccone
S
S
Della Valle
G
G
Lania
L
L
D000595:Amino Acid Sequence; D002874:Chromosome Mapping; D002896:Chromosomes, Human, Pair 6; D003402:Creatine Kinase / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D004268:DNA-Binding Proteins; D004742:Enhancer Elements, Genetic; D005796:Genes; D005799:Genes, Dominant; D017930:Genes, Reporter; D006367:HeLa Cells; D018257:Helix-Loop-Helix Motifs / Q000235:genetics*; D006801:Humans; D051796:Inhibitor of Differentiation Proteins; D008969:Molecular Sequence Data; D017570:MyoD Protein / Q000037:antagonists & inhibitors; D011506:Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors; D014162:Transfection
D018076:DNA, Complementary; D004268:DNA-Binding Proteins; C490128:ID4 protein, human; D051796:Inhibitor of Differentiation Proteins; D017570:MyoD Protein; D011506:Proteins; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; D003402:Creatine Kinase