Unique CCT repeats mediate transcription of the TWIST1 gene in mesenchymal cell lines.
TWIST1, a basic helix-loop-helix transcription factor, plays critical roles in embryo development, cancer metastasis and mesenchymal progenitor differentiation. Little is known about transcriptional regulation of TWIST1 expression. Here we identified DNA sequences responsible for TWIST1 expression in mesenchymal lineage cell lines. Reporter assays with TWIST1 promoter mutants defined the -102 to -74 sequences that are essential for TWIST1 expression in human and mouse mesenchymal cell lines. Tandem repeats of CCT, but not putative CREB and NF-kappaB sites in the sequences substantially supported activity of the TWIST1 promoter. Electrophoretic mobility shift assay demonstrated that the DNA sequences with the CCT repeats formed complexes with nuclear factors, containing, at least, Sp1 and Sp3. These results suggest critical implication of the CCT repeats in association with Sp1 and Sp3 factors in sustaining expression of the TWIST1 gene in mesenchymal cells.
Ohkuma
Mizue
M
Maxillofacial Orthognathics, Graduate School, Tokyo Medical and Dental University, Tokyo 113-8549, Japan.
Funato
Noriko
N
Higashihori
Norihisa
N
Murakami
Masanori
M
Ohyama
Kimie
K
Nakamura
Masataka
M
D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D015870:Gene Expression; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding; D016329:Sp1 Transcription Factor / Q000378:metabolism; D051705:Sp3 Transcription Factor / Q000378:metabolism; D014158:Transcription, Genetic / Q000235:genetics*; D051879:Twist-Related Protein 1 / Q000235:genetics*
D009687:Nuclear Proteins; D016329:Sp1 Transcription Factor; C103173:TWIST1 protein, human; D051879:Twist-Related Protein 1; D051705:Sp3 Transcription Factor