TY - JOUR
T1 - Cloning of Human Acetyl-CoA Carboxylase β Promoter and Its Regulation by Muscle Regulatory Factors
AU - Lee, Jae Jung
AU - Moon, Young Ah
AU - Ha, Joo Hun
AU - Yoon, Do Jun
AU - Ahn, Yong Ho
AU - Kim, Kyung Sup
PY - 2001/1/26
Y1 - 2001/1/26
N2 - The 280-kDa β-isoform of acetyl-CoA carboxylase (ACCβ) is predominantly expressed in heart and skeletal muscle, whereas the 265-kDa α-isoform (ACCα) is the major ACC in lipogenic tissues. The ACCβ promoter showed myoblast-specific promoter activity and was strongly induced by MyoD in NIH3T3 cells. Serial deletions of the promoter revealed that MyoD acts on the E-boxes located at positions -498 to -403 and on the proximal region including the 5′-untranslated region. Destruction of the E-boxes at positions -498 to -403 by site-directed mutagenesis resulted in a significant decrease of MyoD responsiveness. The "TGAAA" at -32 to -28 and the region around the transcription start site play important roles in basal transcription, probably as a TATA box and an Inr element, respectively. Mutations of another E-box at -14 to -9 and a "GCCTGTCA" sequence at +17 to +24 drastically decreased the MyoD responsiveness. The novel cis-element GCCTGTCA was preferentially bound by MyoD homodimer in EMSA and conferred MyoD responsiveness to a luciferase reporter, which was repressed by the overexpression of E12. This finding is unique since activation via E-boxes is mediated by heterodimers of MyoD and E-proteins. We screened a human skeletal muscle cDNA library to isolate clones expressing proteins that bind to the region around the GCCTGTCA (+8 to +27) sequence, and isolated Myf4 and Myf6 cDNAs. Electrophoretic mobility shift assay showed that recombinant Myf4 and Myf6 bind to this novel cis-element. Moreover, transient expression of Myf6 induced significant activation on the ACCβ promoter or an artificial promoter harboring this novel cis-element. These findings suggest that muscle regulatory factors, such as MyoD, Myf4, and Myf6, contribute to the muscle-specific expression of ACCβ via E-boxes and the novel cis-element GCCTGTCA.
AB - The 280-kDa β-isoform of acetyl-CoA carboxylase (ACCβ) is predominantly expressed in heart and skeletal muscle, whereas the 265-kDa α-isoform (ACCα) is the major ACC in lipogenic tissues. The ACCβ promoter showed myoblast-specific promoter activity and was strongly induced by MyoD in NIH3T3 cells. Serial deletions of the promoter revealed that MyoD acts on the E-boxes located at positions -498 to -403 and on the proximal region including the 5′-untranslated region. Destruction of the E-boxes at positions -498 to -403 by site-directed mutagenesis resulted in a significant decrease of MyoD responsiveness. The "TGAAA" at -32 to -28 and the region around the transcription start site play important roles in basal transcription, probably as a TATA box and an Inr element, respectively. Mutations of another E-box at -14 to -9 and a "GCCTGTCA" sequence at +17 to +24 drastically decreased the MyoD responsiveness. The novel cis-element GCCTGTCA was preferentially bound by MyoD homodimer in EMSA and conferred MyoD responsiveness to a luciferase reporter, which was repressed by the overexpression of E12. This finding is unique since activation via E-boxes is mediated by heterodimers of MyoD and E-proteins. We screened a human skeletal muscle cDNA library to isolate clones expressing proteins that bind to the region around the GCCTGTCA (+8 to +27) sequence, and isolated Myf4 and Myf6 cDNAs. Electrophoretic mobility shift assay showed that recombinant Myf4 and Myf6 bind to this novel cis-element. Moreover, transient expression of Myf6 induced significant activation on the ACCβ promoter or an artificial promoter harboring this novel cis-element. These findings suggest that muscle regulatory factors, such as MyoD, Myf4, and Myf6, contribute to the muscle-specific expression of ACCβ via E-boxes and the novel cis-element GCCTGTCA.
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U2 - 10.1074/jbc.M007002200
DO - 10.1074/jbc.M007002200
M3 - Article
C2 - 11076940
AN - SCOPUS:0035951861
SN - 0021-9258
VL - 276
SP - 2576
EP - 2585
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 4
ER -