Skip to main content
NCBI home page
Plant Physiology logoLink to Plant Physiology
. 1992 Dec;100(4):1815–1822. doi: 10.1104/pp.100.4.1815

Physiological Aspects of Sugar Exchange between the Gametophyte and the Sporophyte of Polytrichum formosum

Sylvie Renault 1,2,3, Jean Louis Bonnemain 1,2,3, Loïc Faye 1,2,3, Jean Pierre Gaudillere 1,2,3
PMCID: PMC1075869  PMID: 16653202

Abstract

The sporophyte of bryophytes is dependent on the gametophyte for its carbon nutrition. This is especially true of the sporophytes of Polytrichum species, and it was generally thought that sucrose was the main form of sugar for long distance transport in the leptom. In Polytrichum formosum, sucrose was the main soluble sugar of the sporophyte and gametophyte tissues, and the highest concentration (about 230 mm) was found in the haustorium. In contrast, sugars collected from the vaginula apoplast were mainly hexoses, with traces of sucrose and trehalose. p-Chloromercuribenzene sulfonate, a nonpermeant inhibitor of the cell wall invertase, strongly reduced the hexose to sucrose ratio. The highest cell wall invertase activity (pH 4.5) was located in the vaginula, whereas the highest activity of a soluble invertase (pH 7.0) was found in both the vaginula and the haustorium. Glucose uptake was carrier-mediated but only weakly dependent on the external pH and the transmembrane electrical gradient, in contrast to amino acid uptake (S. Renault, C. Despeghel-Caussin, J.L. Bonnemain, S. Delrot [1989] Plant Physiol 90: 913-920). Furthermore, addition of 5 or 50 mm glucose to the incubation medium induced a marginal depolarization of the transmembrane potential difference of the transfer cells and had no effect on the pH of this medium. Glucose was converted to sucrose after its absorption into the haustorium. These results demonstrate the noncontinuity of sucrose at the gametophyte/sporophyte interface. They suggest that its conversion to glucose and fructose at this interface, and the subsequent reconversion to sucrose after hexose absorption by haustorium cells, mainly governs sugar accumulation in this latter organ.

Full text

PDF
1815

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Boller T., Kende H. Hydrolytic enzymes in the central vacuole of plant cells. Plant Physiol. 1979 Jun;63(6):1123–1132. doi: 10.1104/pp.63.6.1123. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Giaquinta R. T., Lin W., Sadler N. L., Franceschi V. R. Pathway of Phloem unloading of sucrose in corn roots. Plant Physiol. 1983 Jun;72(2):362–367. doi: 10.1104/pp.72.2.362. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Giaquinta R. Source and sink leaf metabolism in relation to Phloem translocation: carbon partitioning and enzymology. Plant Physiol. 1978 Mar;61(3):380–385. doi: 10.1104/pp.61.3.380. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Gussin A. E., McCormack J. H., Waung L. Y., Gluckin D. S. Trehalase: a new pollen enzyme. Plant Physiol. 1969 Aug;44(8):1163–1168. doi: 10.1104/pp.44.8.1163. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Hatch M. D., Sacher J. A., Glasziou K. T. Sugar Accumulation Cycle in Sugar Cane. I. Studies on Enzymes of the Cycle. Plant Physiol. 1963 May;38(3):338–343. doi: 10.1104/pp.38.3.338. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Hubbard N. L., Huber S. C., Pharr D. M. Sucrose Phosphate Synthase and Acid Invertase as Determinants of Sucrose Concentration in Developing Muskmelon (Cucumis melo L.) Fruits. Plant Physiol. 1989 Dec;91(4):1527–1534. doi: 10.1104/pp.91.4.1527. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Renault S., Despeghel-Caussin C., Bonnemain J. L., Delrot S. The Proton Electrochemical Transmembrane Gradients Generated by the Transfer Cells of the Haustorium of Polytrichum formosum and Their Use in the Uptake of Amino Acids. Plant Physiol. 1989 Jul;90(3):913–920. doi: 10.1104/pp.90.3.913. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Veluthambi K., Mahadevan S., Maheshwari R. Trehalose Toxicity in Cuscuta reflexa: CORRELATION WITH LOW TREHALASE ACTIVITY. Plant Physiol. 1981 Dec;68(6):1369–1374. doi: 10.1104/pp.68.6.1369. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Wyse R. Enzymes Involved in the Postharvest Degradation of Sucrose in Beta vulgaris L. Root Tissue. Plant Physiol. 1974 Mar;53(3):507–508. doi: 10.1104/pp.53.3.507. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Plant Physiology are provided here courtesy of Oxford University Press

RESOURCES