Abstract
A mutant of Arabidopsis thaliana (L.) Heynh. which lacks leaf starch was isolated by screening for plants which did not stain with iodine. The starchless phenotype, confirmed by quantitative enzymic analysis, is caused by a single recessive nuclear mutation which results in a deficiency of the chloroplast isozyme of phosphoglucomutase. When grown in a 12-h photoperiod, leaves of the wild-type accumulated substantial amounts of starch but lower levels of soluble sugars. Under these conditions, the mutant accumulated relatively high levels of soluble sugars. Rates of growth and net photosynthesis of the mutant and wild-type were indistinguishable when the plants were grown in constant illumination. However, in a short photoperiod, the growth of the mutant was severely impaired, the rate of photosynthesis was depressed relative to the wild-type, and the rate of dark respiration, which was high following the onset of darkness, exhibited an uncharacteristic decay throughout the dark period. The altered control of respiration by the mutant, which may be related to the relatively high levels of soluble carbohydrate that accumulate in the leaf and stem tissue, is believed to be partially responsible for the low growth rate of the mutant in short days. The depressed photosynthetic capacity of the mutant may also reflect a metabolic adaptation to the accumulation of high levels of soluble carbohydrate which mimics the effects of alterations in source/sink ratio. The activities of sucrose phosphate synthase and acid invertase are significantly higher in the mutant than in the wild-type whereas ADP-glucose pyrophosphorylase activity is lower. This suggests that the activities of these enzymes may be modulated in response to metabolite concentrations or flux through the pathways.
Full text
PDF






Images in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Azcón-Bieto J. Inhibition of photosynthesis by carbohydrates in wheat leaves. Plant Physiol. 1983 Nov;73(3):681–686. doi: 10.1104/pp.73.3.681. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Azcón-Bieto J., Lambers H., Day D. A. Effect of photosynthesis and carbohydrate status on respiratory rates and the involvement of the alternative pathway in leaf respiration. Plant Physiol. 1983 Jul;72(3):598–603. doi: 10.1104/pp.72.3.598. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Azcón-Bieto J., Osmond C. B. Relationship between Photosynthesis and Respiration: The Effect of Carbohydrate Status on the Rate of CO(2) Production by Respiration in Darkened and Illuminated Wheat Leaves. Plant Physiol. 1983 Mar;71(3):574–581. doi: 10.1104/pp.71.3.574. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chatterton N. J., Silvius J. E. Photosynthate Partitioning into Starch in Soybean Leaves: I. Effects of Photoperiod versus Photosynthetic Period Duration. Plant Physiol. 1979 Nov;64(5):749–753. doi: 10.1104/pp.64.5.749. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ching T. M. A sensitive and simple assay of starch synthase activity with pyruvate kinase and luciferase. Anal Biochem. 1982 May 1;122(1):139–143. doi: 10.1016/0003-2697(82)90262-7. [DOI] [PubMed] [Google Scholar]
- Doehlert D. C., Huber S. C. Regulation of Spinach Leaf Sucrose Phosphate Synthase by Glucose-6-Phosphate, Inorganic Phosphate, and pH. Plant Physiol. 1983 Dec;73(4):989–994. doi: 10.1104/pp.73.4.989. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dry I. B., Wiskich J. T. Role of the external adenosine triphosphate/adenosine diphosphate ratio in the control of plant mitochondrial respiration. Arch Biochem Biophys. 1982 Aug;217(1):72–79. doi: 10.1016/0003-9861(82)90480-5. [DOI] [PubMed] [Google Scholar]
- Gifford R. M., Thorne J. H., Hitz W. D., Giaquinta R. T. Crop productivity and photoassimilate partitioning. Science. 1984 Aug 24;225(4664):801–808. doi: 10.1126/science.225.4664.801. [DOI] [PubMed] [Google Scholar]
- Gottlieb L. D. Conservation and duplication of isozymes in plants. Science. 1982 Apr 23;216(4544):373–380. doi: 10.1126/science.216.4544.373. [DOI] [PubMed] [Google Scholar]
- Huber S. C. Biochemical basis for effects of k-deficiency on assimilate export rate and accumulation of soluble sugars in soybean leaves. Plant Physiol. 1984 Oct;76(2):424–430. doi: 10.1104/pp.76.2.424. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Huber S. C. Role of sucrose-phosphate synthase in partitioning of carbon in leaves. Plant Physiol. 1983 Apr;71(4):818–821. doi: 10.1104/pp.71.4.818. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mondal M. H., Brun W. A., Brenner M. L. Effects of Sink Removal on Photosynthesis and Senescence in Leaves of Soybean (Glycine max L.) Plants. Plant Physiol. 1978 Mar;61(3):394–397. doi: 10.1104/pp.61.3.394. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Outlaw W. H., Tarczynski M. C. Guard Cell Starch Biosynthesis Regulated by Effectors of ADP-Glucose Pyrophosphorylase. Plant Physiol. 1984 Feb;74(2):424–429. doi: 10.1104/pp.74.2.424. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Potter J. R. Maintenance of High Photosynthetic Rates during the Accumulation of High Leaf Starch Levels in Sunflower and Soybean. Plant Physiol. 1980 Sep;66(3):528–531. doi: 10.1104/pp.66.3.528. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Robinson J. M. Photosynthetic Carbon Metabolism in Leaves and Isolated Chloroplasts from Spinach Plants Grown under Short and Intermediate Photosynthetic Periods. Plant Physiol. 1984 Jun;75(2):397–409. doi: 10.1104/pp.75.2.397. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rufty T. W., Huber S. C. Changes in Starch Formation and Activities of Sucrose Phosphate Synthase and Cytoplasmic Fructose-1,6-bisphosphatase in Response to Source-Sink Alterations. Plant Physiol. 1983 Jun;72(2):474–480. doi: 10.1104/pp.72.2.474. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Shaw C. R., Prasad R. Starch gel electrophoresis of enzymes--a compilation of recipes. Biochem Genet. 1970 Apr;4(2):297–320. doi: 10.1007/BF00485780. [DOI] [PubMed] [Google Scholar]
- Sowokinos J. R. Pyrophosphorylases in Solanum tuberosum: I. Changes in ADP-Glucose and UDP-Glucose Pyrophosphorylase Activities Associated with Starch Biosynthesis during Tuberization, Maturation, and Storage of Potatoes. Plant Physiol. 1976 Jan;57(1):63–68. doi: 10.1104/pp.57.1.63. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stitt M., Herzog B., Heldt H. W. Control of Photosynthetic Sucrose Synthesis by Fructose 2,6-Bisphosphate : I. Coordination of CO(2) Fixation and Sucrose Synthesis. Plant Physiol. 1984 Jul;75(3):548–553. doi: 10.1104/pp.75.3.548. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tetley R. M., Thimann K. V. The Metabolism of Oat Leaves during Senescence: I. Respiration, Carbohydrate Metabolism, and the Action of Cytokinins. Plant Physiol. 1974 Sep;54(3):294–303. doi: 10.1104/pp.54.3.294. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wintermans J. F., de Mots A. Spectrophotometric characteristics of chlorophylls a and b and their pheophytins in ethanol. Biochim Biophys Acta. 1965 Nov 29;109(2):448–453. doi: 10.1016/0926-6585(65)90170-6. [DOI] [PubMed] [Google Scholar]

