A cytosolic invertase is required for normal growth and cell development in the model legume, Lotus japonicus
Open Access
- 27 May 2009
- journal article
- research article
- Published by Oxford University Press (OUP) in Journal of Experimental Botany
- Vol. 60 (12), 3353-3365
- https://doi.org/10.1093/jxb/erp169
Abstract
Neutral/alkaline invertases are a subgroup, confined to plants and cyanobacteria, of a diverse family of enzymes. A family of seven closely-related genes, LjINV1–LjINV7, is described here and their expression in the model legume, Lotus japonicus, is examined. LjINV1 previously identified as encoding a nodule-enhanced isoform is the predominant isoform present in all parts of the plant. Mutants for two isoforms, LjINV1 and LjINV2, were isolated using TILLING. A premature stop codon allele of LjINV2 had no effect on enzyme activity nor did it show a visible phenotype. For LjINV1, premature stop codon and missense mutations were obtained and the phenotype of the mutants examined. Recovery of homozygous mutants was problematic, but their phenotype showed a severe reduction in growth of the root and the shoot, a change in cellular development, and impaired flowering. The cellular organization of both roots and leaves was altered; leaves were smaller and thicker with extra layers of cells and roots showed an extended and broader zone of cell division. Moreover, anthers contained no pollen. Both heterozygotes and homozygous mutants showed decreased amounts of enzyme activity in nodules and shoot tips. Shoot tips also contained up to a 9-fold increased level of sucrose. However, mutants were capable of forming functional root nodules. LjINV1 is therefore crucial to whole plant development, but is clearly not essential for nodule formation or function.Keywords
This publication has 29 references indexed in Scilit:
- Normal growth of Arabidopsis requires cytosolic invertase but not sucrose synthaseProceedings of the National Academy of Sciences, 2009
- An alternate sucrose binding mode in the E203Q Arabidopsis invertase mutant: An X‐ray crystallography and docking studyProteins-Structure Function and Bioinformatics, 2007
- Antisense Repression of the Medicago truncatula Nodule-Enhanced Sucrose Synthase Leads to a Handicapped Nitrogen Fixation Mirrored by Specific Alterations in the Symbiotic Transcriptome and MetabolomePlant Physiology, 2007
- TILLING Mutants of Lotus japonicus Reveal That Nitrogen Assimilation and Fixation Can Occur in the Absence of Nodule-Enhanced Sucrose SynthasePlant Physiology, 2007
- PIP5K9, an Arabidopsis Phosphatidylinositol Monophosphate Kinase, Interacts with a Cytosolic Invertase to Negatively Regulate Sugar-Mediated Root GrowthPlant Cell, 2007
- Metabolic control of seedling development by invertasesFunctional Plant Biology, 2007
- A TILLING Reverse Genetics Tool and a Web-Accessible Collection of Mutants of the Legume Lotus japonicusPlant Physiology, 2003
- Metabolism of Sugars in the Endosperm of Developing Seeds of Oilseed RapePlant Physiology, 2003
- Analysis of Relative Gene Expression Data Using Real-Time Quantitative PCR and the 2−ΔΔCT MethodMethods, 2001
- Mutations at therug4locus alter the carbon and nitrogen metabolism of pea plants through an effect on sucrose synthaseThe Plant Journal, 1999