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  • 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
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