| DOI | Resolve DOI: https://doi.org/10.1104/pp.122.4.1193 |
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| Author | Search for: Periappuram, Cyril1; Search for: Steinhauer, Lee1; Search for: Barton, Dennis L.1; Search for: Taylor, David1; Search for: Chatson, Brock1; Search for: Zou, Jitao1 |
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| Affiliation | - National Research Council Canada. NRC Plant Biotechnology Institute
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| Format | Text, Article |
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| Abstract | An Arabidopsis cDNA (AtPGMp) encoding the plastidic phosphoglucomutase (PGM) predicted a 623-amino acid protein with an N-terminal sequence typical of a plastid signal peptide. Expression of a recombinant protein inEscherichia coli confirmed its enzyme activity. The recombinant enzyme had an apparent Kₘ value of 98.5 μM and a Vₘₐₓ of 4.48 μmol min⁻¹ (mg protein)⁻¹. The Calvin cycle intermediates fructose-1,6-bisphosphate and ribulose-1,5-bisphosphate exerted an inhibitory effect on PGM activity, supporting its proposed involvement in controlling photosynthetic carbon flow. A point mutation was identified in the AtPGMp gene of the Arabidopsis pgm-1 mutant. The mutation in the mutant transcript generated a stop codon at about one third of the wild-type open reading frame, and thus rendered the polypeptide nonfunctional. Storage lipid analysis of the pgm-1 mutant seeds showed a 40% reduction in oil content compared with that of wild type. Our results indicate that plastidic PGM is an important factor affecting carbon flux in triacylglycerol accumulation in oilseed plants, most likely through its essential role in starch synthesis. |
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| Publication date | 2000-04-01 |
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| Publisher | Oxford Academic
American Society of Plant Biologists |
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| In | |
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| Language | English |
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| Peer reviewed | Yes |
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| NPARC number | 13052560 |
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| Export citation | Export as RIS |
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| Report a correction | Report a correction (opens in a new tab) |
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| Record identifier | b8ea1e6d-6b54-405c-9a64-5a026a8c709d |
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| Record created | 2009-11-25 |
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| Record modified | 2023-04-14 |
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