Muscle-specific transcriptional activation by CArG box requires either homophilic or heterophilic interactions of the CArG box binding factors.
CArG boxes (CC(A/T)6GG sequences) are present in various promoters and are able to confer two different types of transcriptional responsiveness: serum inducibility and muscle-specific activation. Inserted upstream from the ubiquitous HSV thymidine kinase promoter, multimerized HCA1 boxes (human cardiac alpha-actin proximal CArG box) behave as strong muscle-specific activating elements. Transient expression assay was used to determine whether the muscle-specific transcriptional activation by the CArG boxes depends on the presence in the vicinity of other specific cis-acting DNA elements. Our results show that no specific association between different regulatory binding sites is required for the myogenic activity of a CArG box and that CArG elements are able to stimulate transcription in myogenic cells through either homophilic or heterophilic interactions of the CArG box binding factors.
Soulez
M
M
ICGM, U129, INSERM, Paris, France.
Tuil
D
D
Kahn
A
A
Phan-Dinh-Tuy
F
F
D000199:Actins / Q000235:genetics; D000818:Animals; D001483:Base Sequence; D006528:Carcinoma, Hepatocellular; D002460:Cell Line; D002999:Clone Cells; D004268:DNA-Binding Proteins / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans; D007739:L Cells; D008113:Liver Neoplasms; D051379:Mice; D008969:Molecular Sequence Data; D009132:Muscles / Q000378:metabolism*; D010957:Plasmids; D011401:Promoter Regions, Genetic; D018139:Simplexvirus / Q000201:enzymology / Q000235:genetics; D013937:Thymidine Kinase / Q000235:genetics; D014158:Transcription, Genetic; D014162:Transfection; D014407:Tumor Cells, Cultured
D000199:Actins; D004268:DNA-Binding Proteins; D013937:Thymidine Kinase