Project/Area Number |
09680625
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Functional biochemistry
|
Research Institution | University of Tokushima |
Principal Investigator |
MOTOKAWA Yutaro University of Tokushima, Institute for Enzyme Research, Professor, 分子酵素学研究センター, 教授 (40004585)
|
Co-Investigator(Kenkyū-buntansha) |
IKEDA Kazuko University of Tokushima, Institute for Enzyme Research, Research Associate, 分子酵素学研究センター, 助手 (10108863)
|
Project Period (FY) |
1997 – 1998
|
Project Status |
Completed (Fiscal Year 1998)
|
Budget Amount *help |
¥3,400,000 (Direct Cost: ¥3,400,000)
Fiscal Year 1998: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 1997: ¥2,700,000 (Direct Cost: ¥2,700,000)
|
Keywords | lipoyltransferase / lipoic acid / genomic structure / chromosomal mapping / クローニング / 発現 / cDNA / lipoate-protein ligase |
Research Abstract |
Lipoic acid is a prosthetic group of H-proteins of the glycine cleavage system and the acyltransferase components of the pyruvate, alpha-ketoglutarate, and branched chain alpha-ketoacid dehydrogenase complexes. We have isolated lipoyltransferase that catalyzes the transfer of lipoic acid to proteins from bovine liver and characterized the enzyme. In the present study we isolated cDNAs for bovine and human lipoyltransferase, and following results were obtained. 1) We cloned lipoyltransferase cDNA from a bovine liver cDNA library. The cDNA insert contained a 1119-base pair open reading frame encoding a precursor peptide of 373 amino acids including a mitochondrial targeting signal of 26 amino acids. 2) We isolated human lipoyltransferase cDNA and genomic DNA.The cDNA insert contained a 1119-bp open reading frame encoding a precursor peptide of 373 amino acids. Predicted amino acid sequence of the protein shares 88 and 31% identity with bovine lipoyltransferase and Escherichia coli lipoate-protein ligase A.respectively. 3) Northern blot analyses of poly(A)^+ RNA indicated a major species of about 1.5 kb. mRNA levels of lipoyltransferase were highest in skeletal muscle and heart, showing good correlation with those of dihydrolipoamide acyltransfease subunits of pyruvate, alpha-ketoglutarate, and branched chain alpha-ketoacid dehydrogenase complexes and H-protein of the glycine cleavage system which accept lipoic acid as a prosthetic group. 4) The human lipoyltransferase gene is composed of four exons and three introns spanning approximately 8 kb of genomic DNA.The human lipoyltransferase gene was localized to chromosome band 2q11.2 by fluorescence in situ hybridization.
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