Functional analysis of folate polyglutamylation and its essential role in plant metabolism and development

Autor: Mehrshahi, Payam, Gonzalez-Jorge, Sabrina, Akhtar, Tariq A, Ward, Jane L, Santoyo-Castelazo, Anahi, Marcus, Susan E, Lara-Núñez, Aurora, Ravanel, Stéphane, Hawkins, Nathaniel D, Beale, Michael H, Barrett, David A, Knox, J Paul, Gregory, Jesse F, Hanson, Andrew D, Bennett, Malcolm J, Dellapenna, Dean
Přispěvatelé: Department of Biochemistry and Molecular Biology, Michigan State University [East Lansing], Michigan State University System-Michigan State University System, School of Biosciences, University of Nottingham, UK (UON), Horticultural Sciences Department, University of Florida [Gainesville] (UF), The National Centre for Plant and Microbial Metabolomics, School of Pharmacy, Centre for Plant Sciences [Leeds], University of Leeds-Faculty of Biological Sciences-Institute of Integrative and Comparative Biology, Food Science and Human Nutrition Department, Laboratoire de physiologie cellulaire végétale (LPCV), Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Recherche Agronomique (INRA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), University of Florida [Gainesville], Université Joseph Fourier - Grenoble 1 (UJF)-Institut National de la Recherche Agronomique (INRA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA)
Jazyk: angličtina
Rok vydání: 2010
Předmět:
Zdroj: Plant Journal
Plant Journal, 2010, 64 (2), pp.267-79. ⟨10.1111/j.1365-313X.2010.04336.x⟩
Plant Journal, Wiley, 2010, 64 (2), pp.267-79. ⟨10.1111/j.1365-313X.2010.04336.x⟩
ISSN: 0960-7412
1365-313X
DOI: 10.1111/j.1365-313X.2010.04336.x⟩
Popis: International audience; Cellular folates function as co-enzymes in one-carbon metabolism and are predominantly decorated with a polyglutamate tail that enhances co-enzyme affinity, subcellular compartmentation and stability. Polyglutamylation is catalysed by folylpolyglutamate synthetases (FPGSs) that are specified by three genes in Arabidopsis, FPGS1, 2 and 3, which reportedly encode plastidic, mitochondrial and cytosolic isoforms, respectively. A mutational approach was used to probe the functional importance of folate polyglutamylation in one-carbon metabolism and development. Biochemical analysis of single FPGS loss-of-function mutants established that folate polyglutamylation is essential for organellar and whole-plant folate homeostasis. However, polyglutamylated folates were still detectable, albeit at lower levels, in organelles isolated from the corresponding isozyme knockout lines, e.g. in plastids and mitochondria of the fpgs1 (plastidial) and fpgs2 (mitochondrial) mutants. This result is surprising given the purported single-compartment targeting of each FPGS isozyme. These results indicate redundancy in compartmentalised FPGS activity, which in turn explains the lack of anticipated phenotypic defects for the single FPGS mutants. In agreement with this hypothesis, fpgs1 fpgs2 double mutants were embryo-lethal, fpgs2 fpgs3 mutants exhibited seedling lethality, and fpgs1 fpgs3 mutants were dwarfed with reduced fertility. These phenotypic, metabolic and genetic observations are consistent with targeting of one or more FPGS isozymes to multiple organelles. These data confirm the importance of polyglutamylation in folate compartmentation, folate homeostasis and folate-dependent metabolic processes, including photorespiration, methionine and pantothenate biosynthesis.
Databáze: OpenAIRE
Externí odkaz: