title: Cytosolic phosphorylating glyceraldehyde-3-phosphate dehydrogenases affect Arabidopsis cellular metabolism and promote seed oil accumulation.
abstract: The cytosolic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPC) catalyzes a key reaction in glycolysis, but its contribution to plant metabolism and growth are not well defined. Here, we show that two cytosolic GAPCs play important roles in cellular metabolism and seed oil accumulation. Knockout or overexpression of GAPCs caused significant changes in the level of intermediates in the glycolytic pathway and the ratios of ATP/ADP and NAD(P)H/NAD(P). Two double knockout seeds had ∼3% of dry weight decrease in oil content compared with that of the wild type. In transgenic seeds under the constitutive 35S promoter, oil content was increased up to 42% of dry weight compared with 36% in the wild type and the fatty acid composition was altered; however, these transgenic lines exhibited decreased fertility. Seed-specific overexpression lines had >3% increase in seed oil without compromised seed yield or fecundity. The results demonstrate that GAPC levels play important roles in the overall cellular production of reductants, energy, and carbohydrate metabolites and that GAPC levels are directly correlated with seed oil accumulation. Changes in cellular metabolites and cofactor levels highlight the complexity and tolerance of Arabidopsis thaliana cells to the metabolic perturbation. Further implications for metabolic engineering of seed oil production are discussed.
authors.affiliation: Department of Biology, University of Missouri, St. Louis, Missouri 63121 Donald Danforth Plant Science Center, St. Louis, Missouri 63132.
authors.forename: Liang
authors.initials: L
authors.lastname: Guo
authors.affiliation: Donald Danforth Plant Science Center, St. Louis, Missouri 63132.
authors.forename: Fangfang
authors.initials: F
authors.lastname: Ma
authors.affiliation: Department of Biology, University of Missouri, St. Louis, Missouri 63121 Donald Danforth Plant Science Center, St. Louis, Missouri 63132.
authors.forename: Fang
authors.initials: F
authors.lastname: Wei
authors.affiliation: Department of Biology, University of Missouri, St. Louis, Missouri 63121 Donald Danforth Plant Science Center, St. Louis, Missouri 63132.
authors.forename: Brian
authors.initials: B
authors.lastname: Fanella
authors.affiliation: Donald Danforth Plant Science Center, St. Louis, Missouri 63132 U.S. Department of Agriculture-Agricultural Research Service, Plant Genetics Research Unit, St. Louis, Missouri 63132.
authors.forename: Doug K
authors.initials: DK
authors.lastname: Allen
authors.affiliation: Department of Biology, University of Missouri, St. Louis, Missouri 63121 Donald Danforth Plant Science Center, St. Louis, Missouri 63132 swang@danforthcenter.org.
authors.forename: Xuemin
authors.identifier: http://orcid.org/0000-0002-6251-6745
authors.initials: X
authors.lastname: Wang
mesh_terms: D017360:Arabidopsis / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D003600:Cytosol / Q000201:enzymology; D005227:Fatty Acids / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D024581:Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating) / Q000235:genetics / Q000378:metabolism*; D006019:Glycolysis; D018515:Plant Leaves / Q000737:chemistry / Q000201:enzymology / Q000235:genetics; D010938:Plant Oils / Q000378:metabolism*; D030821:Plants, Genetically Modified; D012639:Seeds / Q000737:chemistry / Q000201:enzymology / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D005227:Fatty Acids; D010938:Plant Oils; C585192:GAPC1 protein, Arabidopsis; D024581:Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating)