TY - JOUR
T1 - PLEIOTROPIC REGULATORY LOCUS 1 (PRL1) Integrates the Regulation of Sugar Responses with Isoprenoid Metabolism in Arabidopsis
AU - Flores-Perez, Ursula
AU - Perez-Gil, Jordi
AU - Closa, Marta
AU - Wright, Louwrance P.
AU - Botella-Pavia, Patricia
AU - Phillips, Michael A.
AU - Ferrer, Albert
AU - Gershenzon, Jonathan
AU - Rodriguez-Concepcion, Manuel
PY - 2010/1
Y1 - 2010/1
N2 - The biosynthesis of isoprenoids in plant cells occurs from precursors produced in the cytosol by the mevalonate (MVA) pathway and in the plastid by the methylerythritol 4-phosphate (MEP) pathway, but little is known about the mechanisms coordinating both pathways. Evidence of the importance of sugar signaling for such coordination in Arabidopsis thaliana is provided here by the characterization of a mutant showing an increased accumulation of MEP-derived isoprenoid products (chlorophylls and carotenoids) without changes in the levels of relevant MEP pathway transcripts, proteins, or enzyme activities. This mutant was found to be a new loss-of-function allele of PRL1 (Pleiotropic Regulatory Locus 1), a gene encoding a conserved WD-protein that functions as a global regulator of sugar, stress, and hormone responses, in part by inhibition of SNF1-related protein kinases (SnRK1). Consistent with the reported role of SnRK1 kinases in the phosphorylation and inactivation of the main regulatory enzyme of the MVA pathway (hydroxymethylglutaryl coenzyme-A reductase), its activity but not transcript or protein levels was reduced in prl1 seedlings. However, the accumulation of MVA-derived end products (sterols) was unaltered in mutant seedlings. Sucrose supplementation to wild-type seedlings phenocopied the prl1 mutation in terms of isoprenoid metabolism, suggesting that the observed isoprenoid phenotypes result from the increased sugar accumulation in the prl1 mutant. In summary, PRL1 appears to coordinate isoprenoid metabolism with sugar, hormone, and stress responses.
AB - The biosynthesis of isoprenoids in plant cells occurs from precursors produced in the cytosol by the mevalonate (MVA) pathway and in the plastid by the methylerythritol 4-phosphate (MEP) pathway, but little is known about the mechanisms coordinating both pathways. Evidence of the importance of sugar signaling for such coordination in Arabidopsis thaliana is provided here by the characterization of a mutant showing an increased accumulation of MEP-derived isoprenoid products (chlorophylls and carotenoids) without changes in the levels of relevant MEP pathway transcripts, proteins, or enzyme activities. This mutant was found to be a new loss-of-function allele of PRL1 (Pleiotropic Regulatory Locus 1), a gene encoding a conserved WD-protein that functions as a global regulator of sugar, stress, and hormone responses, in part by inhibition of SNF1-related protein kinases (SnRK1). Consistent with the reported role of SnRK1 kinases in the phosphorylation and inactivation of the main regulatory enzyme of the MVA pathway (hydroxymethylglutaryl coenzyme-A reductase), its activity but not transcript or protein levels was reduced in prl1 seedlings. However, the accumulation of MVA-derived end products (sterols) was unaltered in mutant seedlings. Sucrose supplementation to wild-type seedlings phenocopied the prl1 mutation in terms of isoprenoid metabolism, suggesting that the observed isoprenoid phenotypes result from the increased sugar accumulation in the prl1 mutant. In summary, PRL1 appears to coordinate isoprenoid metabolism with sugar, hormone, and stress responses.
KW - Carbohydrate metabolism
KW - metabolic regulation
KW - secondary metabolism—terpenoids
KW - isoprenoids
KW - carotenoids
KW - Arabidopsis
U2 - 10.1093/mp/ssp100
DO - 10.1093/mp/ssp100
M3 - Article
C2 - 20008452
SN - 1674-2052
VL - 3
SP - 101
EP - 112
JO - Molecular Plant
JF - Molecular Plant
IS - 1
ER -