Folic acid is metabolized in tissues to folypolyglutamates, which are coenzymes in, and potential regulators of, metabolic cycles involving the syntheses of thymidylate, purines and amino acids. The nutritional and physiological relevance of potential regulatory features that control folate accumulation by tissues and control one carbon availability for folate-dependent reactions will be investigated in the rat and in mammalian cell culture. Several approaches will be used. 1. Model cell systems defective in cytosolic and/or mitochondrial folate metabolism will be developed by transfecting mutant mammalian cells with the folypoly- glutamate synthetase gene. 2.Mitochondrial folates and folate-dependent enzymes will be identified and the metabolism of one carbon precursors studied. The role of the mitochondria in providing one carbon units for mitochondrial and cytosolic folate-dependent reactions will be assessed using mammalian cell transfectants as model systems. 3.The regulation of one carbon entry into the folate pool and the synthesis and fate of cytosolic and mitochondrial glycine will be studied in model cells. 4.The regulation of folate-dependent methionine synthesis and the role of the methionine cycle in sparing the nutritional need for methionine and in the retention of absorbed folate by tissues will be investigated. The long term goals of the project are to understand the basic mechanisms by which folate homeostasis and one carbon metabolism are regulated and to develop models explaining how these important physiological processes are disturbed under a number of nutritional conditions. The metabolic cycles under study play a central role in the de novo synthesis of the methyl group of methionine, a group that is used extensively in metabolic control processes, and in precursor availability for DNA and protein synthesis. An understanding of how these cycles are regulated should also provide information on rate limiting steps in one carbon metabolism and suggest target enzymes for anitmetabolite intervention.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK042033-05
Application #
2142057
Study Section
Nutrition Study Section (NTN)
Project Start
1990-01-01
Project End
1994-12-31
Budget Start
1994-01-01
Budget End
1994-12-31
Support Year
5
Fiscal Year
1994
Total Cost
Indirect Cost
Name
University of California Berkeley
Department
Nutrition
Type
Schools of Earth Sciences/Natur
DUNS #
094878337
City
Berkeley
State
CA
Country
United States
Zip Code
94704
Schaevitz, Laura R; Picker, Jonathan D; Rana, Jasmine et al. (2012) Glutamate carboxypeptidase II and folate deficiencies result in reciprocal protection against cognitive and social deficits in mice: implications for neurodevelopmental disorders. Dev Neurobiol 72:891-905
MacFarlane, Amanda J; Perry, Cheryll A; Girnary, Hussein H et al. (2009) Mthfd1 is an essential gene in mice and alters biomarkers of impaired one-carbon metabolism. J Biol Chem 284:1533-9
Lawrance, Andrea K; Deng, Liyuan; Brody, Lawrence C et al. (2007) Genetic and nutritional deficiencies in folate metabolism influence tumorigenicity in Apcmin/+ mice. J Nutr Biochem 18:305-12
Davis, Steven R; Quinlivan, Eoin P; Shelnutt, Karla P et al. (2005) Homocysteine synthesis is elevated but total remethylation is unchanged by the methylenetetrahydrofolate reductase 677C->T polymorphism and by dietary folate restriction in young women. J Nutr 135:1045-50
Lim, Unhee; Peng, Kun; Shane, Barry et al. (2005) Polymorphisms in cytoplasmic serine hydroxymethyltransferase and methylenetetrahydrofolate reductase affect the risk of cardiovascular disease in men. J Nutr 135:1989-94
Quinlivan, Eoin P; Davis, Steven R; Shelnutt, Karla P et al. (2005) Methylenetetrahydrofolate reductase 677C->T polymorphism and folate status affect one-carbon incorporation into human DNA deoxynucleosides. J Nutr 135:389-96
Dayal, Sanjana; Devlin, Angela M; McCaw, Ryan B et al. (2005) Cerebral vascular dysfunction in methionine synthase-deficient mice. Circulation 112:737-44
O'Leary, Valerie B; Mills, James L; Pangilinan, Faith et al. (2005) Analysis of methionine synthase reductase polymorphisms for neural tube defects risk association. Mol Genet Metab 85:220-7
Davis, Steven R; Stacpoole, Peter W; Williamson, Jerry et al. (2004) Tracer-derived total and folate-dependent homocysteine remethylation and synthesis rates in humans indicate that serine is the main one-carbon donor. Am J Physiol Endocrinol Metab 286:E272-9
Prasannan, Priya; Pike, Schuyler; Peng, Kun et al. (2003) Human mitochondrial C1-tetrahydrofolate synthase: gene structure, tissue distribution of the mRNA, and immunolocalization in Chinese hamster ovary calls. J Biol Chem 278:43178-87

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