Arabidopsis trehalose-6-phosphate synthase 1 is essential for normal vegetative growth and transition to flowering

• Published in: Plant physiology (Bethesda) Vol. 135; no. 2; pp. 969 - 977
• Main Authors: Dijken, A.J.H. van, Schluepmann, H, Smeekens, S.C.M
• Format: Journal Article
• Language: English
• Published: United States American Society of Plant Biologists 01.06.2004
• Subjects: Arabidopsis - enzymology; Arabidopsis - genetics; Arabidopsis - growth & development; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Arabidopsis thaliana; Biosynthesis; Cloning, Molecular; Development and Hormone Action; DNA, Complementary - chemistry; DNA, Complementary - genetics; Embryos; Flowering; Flowers - enzymology; Flowers - growth & development; Gene Deletion; gene expression regulation; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Plant; Glucosyltransferases - genetics; Glucosyltransferases - metabolism; hexosyltransferases; molecular cloning; Mutation; Phenotypes; phenotypic variation; Plant growth; plant morphology; plant proteins; Plant roots; Plant Roots - enzymology; Plant Roots - genetics; Plant Roots - growth & development; Plant Shoots - enzymology; Plant Shoots - genetics; Plant Shoots - growth & development; Plants; promoter regions; root growth; Seedlings; Seeds; Sequence Analysis, DNA; shoots; Transgenic plants; trehalose; trehalose-6-phosphate synthase; vegetative growth
• ISSN: 0032-0889; 1532-2548
• DOI: 10.1104/pp.104.039743

In resurrection plants and yeast, trehalose has a function in stress protection, but the absence of measurable amounts of trehalose in other plants precludes such a function. The identification of a trehalose biosynthetic pathway in angiosperms raises questions on the function of trehalose metabolism in nonresurrection plants. We previously identified a mutant in the Arabidopsis trehalose biosynthesis gene AtTPS1. Plants homozygous for the tps1 mutation do not develop mature seeds (Eastmond et al., 2002). AtTPS1 expression analysis and the spatial and temporal activity of its promoter suggest that this gene is active outside the seed-filling stage of development as well. A generally low expression is observed in all organs analyzed, peaking in metabolic sinks such as flower buds, ripening siliques, and young rosette leaves. The arrested tps1/tps1 embryonic state could be rescued using a dexamethasone-inducible AtTPS1 expression system enabling generation of homozygous mutant plants. When depleted in AtTPS1 expression, such mutant plants show reduced root growth, which is correlated with a reduced root meristematic region. Moreover, tps1/tps1 plants are retarded in growth and remain generative during their lifetime. Absence of Trehalose-6-Phosphate Synthase 1 in Arabidopsis plants precludes transition to flowering.