Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


  • NSF Public Access
  • Search Results
  • The serine–glycine–one-carbon metabolic network orchestrates changes in nitrogen and sulfur metabolism and shapes plant development
Title: The serine–glycine–one-carbon metabolic network orchestrates changes in nitrogen and sulfur metabolism and shapes plant development
Abstract L-serine (Ser) and L-glycine (Gly) are critically important for the overall functioning of primary metabolism. We investigated the interaction of the phosphorylated pathway of Ser biosynthesis (PPSB) with the photorespiration-associated glycolate pathway of Ser biosynthesis (GPSB) using Arabidopsis thaliana PPSB-deficient lines, GPSB-deficient mutants, and crosses of PPSB with GPSB mutants. PPSB-deficient lines mainly showed retarded primary root growth. Mutation of the photorespiratory enzyme Ser-hydroxymethyltransferase 1 (SHMT1) in a PPSB-deficient background resumed primary root growth and induced a change in the plant metabolic pattern between roots and shoots. Grafting experiments demonstrated that metabolic changes in shoots were responsible for the changes in double mutant development. PPSB disruption led to a reduction in nitrogen (N) and sulfur (S) contents in shoots and a general transcriptional response to nutrient deficiency. Disruption of SHMT1 boosted the Gly flux out of the photorespiratory cycle, which increased the levels of the one-carbon (1C) metabolite 5,10-methylene-tetrahydrofolate and S-adenosylmethionine. Furthermore, disrupting SHMT1 reverted the transcriptional response to N and S deprivation and increased N and S contents in shoots of PPSB-deficient lines. Our work provides genetic evidence of the biological relevance of the Ser–Gly–1C metabolic network in N and S metabolism and in interorgan metabolic homeostasis.  more » « less
Award ID(s):
2015828
PAR ID:
10526410
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Oxford Academic
Date Published:
Journal Name:
The Plant Cell
Volume:
36
Issue:
2
ISSN:
1040-4651
Page Range / eLocation ID:
404 to 426
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; ; ; ; ; ; ; (, Journal of Experimental Botany)
    Gibon, Yves (Ed.)
    Abstract The growth and development of maize (Zea mays L.) largely depends on its nutrient uptake through the root. Hence, studying its growth, response, and associated metabolic reprogramming to stress conditions is becoming an important research direction. A genome-scale metabolic model (GSM) for the maize root was developed to study its metabolic reprogramming under nitrogen stress conditions. The model was reconstructed based on the available information from KEGG, UniProt, and MaizeCyc. Transcriptomics data derived from the roots of hydroponically grown maize plants were used to incorporate regulatory constraints in the model and simulate nitrogen-non-limiting (N+) and nitrogen-deficient (N−) condition. Model-predicted flux-sum variability analysis achieved 70% accuracy compared with the experimental change of metabolite levels. In addition to predicting important metabolic reprogramming in central carbon, fatty acid, amino acid, and other secondary metabolism, maize root GSM predicted several metabolites (l-methionine, l-asparagine, l-lysine, cholesterol, and l-pipecolate) playing a regulatory role in the root biomass growth. Furthermore, this study revealed eight phosphatidylcholine and phosphatidylglycerol metabolites which, even though not coupled with biomass production, played a key role in the increased biomass production under N-deficient conditions. Overall, the omics-integrated GSM provides a promising tool to facilitate stress condition analysis for maize root and engineer better stress-tolerant maize genotypes. 
    more » « less
  2. ; ; ; ; ; ; ; ; ; ; et al (, Science)
    Strigolactones (SLs) are methylbutenolide molecules derived from β-carotene through an intermediate carlactonoic acid (CLA). Canonical SLs act as signals to microbes and plants, whereas noncanonical SLs are primarily plant hormones. The cytochrome P450 CYP722C catalyzes a critical step, converting CLA to canonical SLs in most angiosperms. Using synthetic biology, we investigated the function ofCYP722A, an evolutionary predecessor ofCYP722C. CYP722A converts CLA into 16-hydroxy-CLA (16-OH-CLA), a noncanonical SL detected exclusively in the shoots of various flowering plants. 16-OH-CLA application restores control of shoot branching to SL-deficient mutants inArabidopsis thalianaand is perceived by the SL signaling pathway. We hypothesize that biosynthesis of 16-OH-CLA by CYP722A was a metabolic stepping stone in the evolution of canonical SLs that mediate rhizospheric signaling in many flowering plants. 
    more » « less
  3. ; ; (, Frontiers in Plant Science)
    Plants synthesize a diverse array of specialized metabolites that contribute to plant development, growth, protection from biotic and abiotic stressors, and attracting pollinators and seed dispersers. Specialized metabolites are often derived from primary metabolites, such as amino acids, but also can be redirected from intermediates in primary metabolic pathways. In the L-tryptophan (Trp) biosynthetic pathway, the intermediate anthranilate is siphoned away to synthesize volatiles and specialized metabolites. Methyltransferases can produce the O-methyl ester of anthranilate, a grape aroma volatile produced in species such as grapevine, strawberry, citrus, maize, and soybean. O-Methyl anthranilate serves context-dependent roles in attracting insects and deterring herbivores. Methylation at the amine generates N-methyl anthranilate, a precursor for N-methyl anthranilate esters in citrus and antimicrobial avenacins in black oat. This Mini Review explores the regulation of anthranilate within the context of the Trp pathway and its contributions to the biosynthesis of anthranilate-containing volatiles and specialized metabolites. Also highlighted are the roles of anthranilates in plant defensive metabolism and the substrate specificity of anthranilate-using enzymes, as well as unanswered questions about the synthesis, transport, and physiological role of anthranilates. 
    more » « less
  4. ; ; ; ; ; ; ; ; ; ; et al (, Proceedings of the National Academy of Sciences)
    Karrikin (KAR) molecules found in smoke stimulate seed germination of many plant species that emerge after fire. Genetic studies in Arabidopsis thaliana have identified core components of the KAR signaling pathway, including an α/β-hydrolase, KARRIKIN INSENSITIVE2 (KAI2), that is required for KAR responses. Although KAI2 is often considered a KAR receptor, recent evidence suggests that KARs may require metabolism to become bioactive signals. In addition to sensing KARs or a KAR-derived signal, KAI2 is thought to recognize an unknown endogenous signal, KAI2 ligand (KL). We generated loss-of-function mutations in KARRIKIN-UP-REGULATED F-BOX1 ( KUF1 ), which is a transcriptional marker of KAR/KL signaling in A. thaliana and other plants. The kuf1 mutant in Arabidopsis shows several phenotypes that are consistent with enhanced activity of the KAI2 pathway, including reduced hypocotyl elongation, enhanced cotyledon expansion in light-grown seedlings, increased root hair density and elongation, and differential expression of KAR/KL-responsive transcriptional markers. Seedling phenotypes of kuf1 are dependent on KAI2 and its signaling partner MORE AXILLARY GROWTH2 (MAX2). Furthermore, kuf1 mutants are hypersensitive to KAR 1 , but not to other molecules that can signal through KAI2 such as GR24. This implies that kuf1 does not increase the overall responsiveness of the KAI2-dependent signaling pathway, but specifically affects the ability of KAI2 to detect certain signals. We hypothesize that KUF1 imposes feedback inhibition of KL biosynthesis and KAR 1 metabolism. As an F-box protein, KUF1 likely participates in an E3 ubiquitin ligase complex that imposes this regulation through polyubiquitylation of a protein target(s). 
    more » « less
  5. ; ; ; ; ; ; ; (, Plant Direct)
    Abstract Isoprene, a volatile hydrocarbon, is typically emitted from the leaves of many plant species. Given its well‐known function in plant growth and defense aboveground, we examined its effects on root physiology. We used isoprene‐emitting (IE) lines and a non‐emitting (NE) line of Arabidopsis and investigated their performance by analyzing root phenotype, hormone levels, transcriptome, and metabolite profiles under both normal and salt stress conditions. We show that IE lines emitted tiny amounts of isoprene from roots and showed an increased root/shoot ratio compared with NE line. Isoprene emission exerted a noteworthy influence on hormone profiles related to plant growth and stress response, promoting root development and salt‐stress resistance. Methyl erythritol 4‐phosphate pathway metabolites, precursors of isoprene and hormones, were higher in the roots of IE lines than in the NE line. Transcriptome data indicated that the presence of isoprene increased the expression of key genes involved in hormone metabolism/signaling. Our findings reveal that constitutive root isoprene emission sustains root growth under saline conditions by regulating and/or priming hormone biosynthesis and signaling mechanisms and expression of key genes relevant to salt stress defense. 
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Text Encoded Conversion
  • XML
  • Save / Share this Record
  • Send to Email