• We are sorry, but NCBI web applications do not support your browser and may not function properly. More information
Logo of plntphysLink to Publisher's site
Plant Physiol. May 1997; 114(1): 153–160.
PMCID: PMC158289

Carbohydrate Content and Enzyme Metabolism in Developing Canola Siliques.

Abstract

Little biochemical information is available on carbohydrate metabolism in developing canola (Brassica napus L.) silique (pod) wall and seed tissues. This research examines the carbohydrate contents and sucrose (Suc) metabolic enzyme activities in different aged silique wall and seed tissues during oil filling. The silique wall partitioned photosynthate into Suc over starch and predominantly accumulated hexose. The silique wall hexose content and soluble acid invertase activity rapidly fell as embryos progressed from the early- to late-cotyledon developmental stages. A similar trend was not evident for alkaline invertase, Suc synthase (SuSy), and Suc-phosphate synthase. Silique wall SuSy activities were much higher than source leaves at all times and may serve to supply the substrate for secondary cell wall thickening. In young seeds starch was the predominant accumulated carbohydrate over the sampled developmental range. Seed hexose levels dropped as embryos developed from the early- to midcotyledon stage. Hexose and starch were localized to the testa or liquid endosperm, whereas Suc was evenly distributed among seed components. With the switch to oil accumulation, seed SuSy activity increased by 3.6-fold and soluble acid invertase activity decreased by 76%. These data provide valuable baseline knowledge for the genetic manipulation of canola seed carbon partitioning.

Full Text

The Full Text of this article is available as a PDF (848K).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Chourey PS, Nelson OE. The enzymatic deficiency conditioned by the shrunken-1 mutations in maize. Biochem Genet. 1976 Dec;14(11-12):1041–1055. [PubMed]
  • Heim U, Weber H, Bäumlein H, Wobus U. A sucrose-synthase gene of Vicia faba L.: expression pattern in developing seeds in relation to starch synthesis and metabolic regulation. Planta. 1993;191(3):394–401. [PubMed]
  • Ross HA, McRae D, Davies HV. Sucrolytic Enzyme Activities in Cotyledons of the Faba Bean (Developmental Changes and Purification of Alkaline Invertase). Plant Physiol. 1996 May;111(1):329–338. [PMC free article] [PubMed]
  • Vijayagopal P, Figueroa JE, Fontenot JD, Glancy DL. Isolation and characterization of a proteoglycan variant from human aorta exhibiting a marked affinity for low density lipoprotein and demonstration of its enhanced expression in atherosclerotic plaques. Atherosclerosis. 1996 Dec 20;127(2):195–203. [PubMed]
  • Sung SJ, Xu DP, Black CC. Identification of actively filling sucrose sinks. Plant Physiol. 1989 Apr;89(4):1117–1121. [PMC free article] [PubMed]
  • Weber H, Borisjuk L, Heim U, Buchner P, Wobus U. Seed coat-associated invertases of fava bean control both unloading and storage functions: cloning of cDNAs and cell type-specific expression. Plant Cell. 1995 Nov;7(11):1835–1846. [PMC free article] [PubMed]

Articles from Plant Physiology are provided here courtesy of American Society of Plant Biologists

Formats:

Related citations in PubMed

See reviews...See all...

Cited by other articles in PMC

See all...

Links

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...