Protein complex formation in methionine chain-elongation and leucine biosynthesis
Open Access
- 10 February 2021
- journal article
- research article
- Published by Springer Science and Business Media LLC in Scientific Reports
- Vol. 11 (1), 1-8
- https://doi.org/10.1038/s41598-021-82790-4
Abstract
During the past two decades, glucosinolate (GLS) metabolic pathways have been under extensive studies because of the importance of the specialized metabolites in plant defense against herbivores and pathogens. The studies have led to a nearly complete characterization of biosynthetic genes in the reference plant Arabidopsis thaliana. Before methionine incorporation into the core structure of aliphatic GLS, it undergoes chain-elongation through an iterative three-step process recruited from leucine biosynthesis. Although enzymes catalyzing each step of the reaction have been characterized, the regulatory mode is largely unknown. In this study, using three independent approaches, yeast two-hybrid (Y2H), coimmunoprecipitation (Co-IP) and bimolecular fluorescence complementation (BiFC), we uncovered the presence of protein complexes consisting of isopropylmalate isomerase (IPMI) and isopropylmalate dehydrogenase (IPMDH). In addition, simultaneous decreases in both IPMI and IPMDH activities in a leuc:ipmdh1 double mutants resulted in aggregated changes of GLS profiles compared to either leuc or ipmdh1 single mutants. Although the biological importance of the formation of IPMI and IPMDH protein complexes has not been documented in any organisms, these complexes may represent a new regulatory mechanism of substrate channeling in GLS and/or leucine biosynthesis. Since genes encoding the two enzymes are widely distributed in eukaryotic and prokaryotic genomes, such complexes may have universal significance in the regulation of leucine biosynthesis.Funding Information
- National Science Foundation (0845162)
This publication has 31 references indexed in Scilit:
- Integrated Proteomics and Metabolomics of Arabidopsis Acclimation to Gene-Dosage Dependent Perturbation of Isopropylmalate DehydrogenasesPLOS ONE, 2013
- Biochemical and Structural Characterization of the Arabidopsis Bifunctional Enzyme Dethiobiotin Synthetase–Diaminopelargonic Acid Aminotransferase: Evidence for Substrate Channeling in Biotin SynthesisTHE PLANT CELL ONLINE, 2012
- Structural and Functional Evolution of Isopropylmalate Dehydrogenases in the Leucine and Glucosinolate Pathways of Arabidopsis thalianaOnline Journal of Public Health Informatics, 2011
- From Amino Acid to Glucosinolate Biosynthesis: Protein Sequence Changes in the Evolution of Methylthioalkylmalate Synthase in ArabidopsisTHE PLANT CELL ONLINE, 2011
- Arabidopsis thaliana encodes a bacterial-type heterodimeric isopropylmalate isomerase involved in both Leu biosynthesis and the Met chain elongation pathway of glucosinolate formationPlant Molecular Biology, 2009
- Omics-Based Approaches to Methionine Side Chain Elongation in Arabidopsis: Characterization of the Genes Encoding Methylthioalkylmalate Isomerase and Methylthioalkylmalate DehydrogenasePlant and Cell Physiology, 2009
- Enzymology and Evolution of the Pyruvate Pathway to 2-Oxobutyrate in Methanocaldococcus jannaschiiJournal of Bacteriology, 2007
- MAM3 Catalyzes the Formation of All Aliphatic Glucosinolate Chain Lengths in ArabidopsisPlant Physiology, 2007
- Two Arabidopsis Genes (IPMS1 and IPMS2) Encode Isopropylmalate Synthase, the Branchpoint Step in the Biosynthesis of LeucinePlant Physiology, 2006
- Rice XA21 Binding Protein 3 Is a Ubiquitin Ligase Required for Full Xa21-Mediated Disease ResistanceTHE PLANT CELL ONLINE, 2006