Structural organization and regulatory regions of the human medium-chain acyl-CoA dehydrogenase gene.
Structural organization and regulatory regions of the human medium-chain acyl-CoA dehydrogenase gene.
复制标题
人类中链酰基辅酶A脱氢酶基因的结构组织和调控区域。
DOI：
10.1021/bi00116a013
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发表时间：
1992
期刊：
影响因子：
2.9
通讯作者：
Strauss,AW
中科院分区：
文献类型：
--
作者：
Zhang,ZF;Kelly,DP;Kim,JJ;Zhou,YQ;Ogden,ML;Whelan,AJ;Strauss,AW
Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin53226, and Departments of Pediatrics, Biochemistry and Molecular Biophysics, and Medicine, Washington University School of Medicine, St. Louis, Missouri 63110 Received July 16, 1991; Revised Manuscript Received September 24, 1991 abstract: Medium-chain acyl-CoA dehydrogenase (MCAD) is a highly regulated mitochondrial flavo-enzyme that catalyzes the initial reaction in fatty acid/3-oxidation. Deficiency of MCAD is a common inherited defect in energy metabolism. We have previously shown that the mRNA encoding MCAD in an MCAD-deficient child is homozygous for the point mutation A985 to G [Kelly et al.(1990) Proc. Natl. Acad. Sci. USA 87, 9236-9420]. To define the molecular basis of MCAD deficiency and as an initial step in the study of the regulation of MCAD gene expression, we determined the structure and organization of the human MCAD gene. The gene is comprised of 12 exons which span 44 kb of DNA. Comparison of the MCAD gene to MCAD mRNAs from the MCAD-deficient child revealed that missplicing was common, resulting in a variety of exon deletions and intron insertions. The MCAD gene promoter region is extremely GC-rich and lacks prototypical TATA and CAAT boxes. Several regions upstream of the promoter are homologous with mitochondrial enhancers purportedly involved in coordinate expression of nuclear genes encoding mitochondrial proteins. Transfection of chimeric plasmid constructs with 299 bp of upstream sequence into HepG2 cells revealed high-leveltranscriptional activity. We conclude that the precursor MCAD mRNA is misspliced to a high degree and complexity in association with the G985 mutation and the MCAD gene contains a strong promoter which shares some structural features with other “housekeeping” genes encoding mitochondrial proteins.IV^ edium-chain acyl-CoA dehydrogenase (MCAD; 2, 3-oxidoreductase, EC 1.3. 99.3) 1 is a mitochondrial matrix flavoprotein which catalyzes the first reaction in the/3-oxidation of straight-chain fatty acids (Beinert, 1963). It forms an enzyme family with short-and long-chain acyl-CoA dehydrogenases. These three enzymes are homotetramers with subunits of similar size, but they are immunologically distinct with different amino acid sequences (Ikeda et al., 1985). MCAD requires medium-chain-length acyl-coenzyme A
