The human M creatine kinase gene enhancer contains multiple functional interacting domains.
Cis-elements (-933 to -641) upstream of the human M creatine kinase gene cap site contain an enhancer that confers developmental and tissue-specific expression to the chloramphenicol acetyltransferase gene in C2C12 myogenic cells transfected in culture. Division of the enhancer at -770 into a 5' fragment that includes the MyoD binding sites (-933 to -770) and a 3' fragment that includes the MEF-2 binding site (-770 to -641) resulted in two subfragments that showed minimal activity but in combination interacted in a position- and orientation-independent fashion to enhance activity of the SV40 promoter in transient transfection experiments. A 5' enhancer construct (-877 to -832) including only one (the low affinity) MyoD binding site was active when present in multiple copies. In contrast, a 3' enhancer construct (-749 to -732) including the MEF-2 binding site was inactive even when present in multiple copies. However, if the 5' construct was extended to include the high-affinity MyoD binding site (-877 to -803) the 5' and 3' constructs interacted in a position- and orientation-independent fashion to activate the SV40 promoter. Thus, the human M creatine kinase enhancer comprises multiple functional interacting domains.
Trask
R V
RV
Department of Medicine, Washington University School of Medicine, St Louis, MO 63110.
Koster
J C
JC
Ritchie
M E
ME
Billadello
J J
JJ
D016475:3T3 Cells; D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D003402:Creatine Kinase / Q000235:genetics*; D004247:DNA; D004268:DNA-Binding Proteins / Q000378:metabolism; D004742:Enhancer Elements, Genetic; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic
D004268:DNA-Binding Proteins; D004247:DNA; D003402:Creatine Kinase