Spatial metabolomics links polyamine turnover and vascular lipid remodeling to barley spikelet fate
- 1Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany
Abstract
Local metabolic programs can determine whether developing organs maintain growth, differentiate, or degenerate. However, the spatial establishment of such programs during reproductive development remains poorly understood. In cereal inflorescences, this question is closely tied to grain number because the fate of initiated floral primordia is shaped by the developmental position, metabolic support, genotype, and environmental stress. To understand the metabolic logic underlying floral fate in barley (Hordeum vulgare L.), we mapped the spatial distribution of metabolites across the inflorescence in wild-type Bowman and in hvcmf4, a mutant that undergoes premature apical inflorescence degeneration. Amino acid-, carbohydrate-, and chlorophyll-associated metabolites form clear developmental gradients along the inflorescence axis. These gradients are progressively remodeled during developmental pre-anthesis tip degeneration but are both accelerated and spatially distorted in hvcmf4. Within this broader metabolic landscape, two discrete domains stand out. First, spermidine-associated domains specifically marked reproductive meristems, a pattern corroborated by the meristem-enriched expression of polyamine biosynthetic genes. This polyamine-rich meristem state declined as developmental tip degeneration proceeded and was prematurely lost in hvcmf4, where polyamine metabolism appeared to shift toward oxidative breakdown via the polyamine oxidase pathway. Second, lysophosphatidylcholine accumulated specifically at floral attachment and vascular supply zones. The developmental reduction of this bioactive lysophospholipid-associated domain in the apical regions, and its stronger disruption in hvcmf4, coincided with the reprogramming of lipid-remodeling and auxin transport-associated genes, suggesting impaired coordination of lipid signaling, auxin canalization, and vascular support. Together, our study reveals spatial polyamine and lysophospholipid domains that couple meristem maintenance with vascular support, providing a metabolic framework for the fate of developing cereal inflorescences.
Related
- Comparative metabolomics identifies recurrent age-associated pathway remodeling across species
- Smooth muscle DDIT4 exacerbates vascular remodeling in atherosclerosis and vascular injury by impairing PDC activity
- DLGAP5 promotes vascular cell proliferation and remodeling in pulmonary arterial hypertension
- High-fat diet promotes exhaustion-associated T-cell remodeling across vascular and lymphoid tissues in atherosclerosis-prone mice
- Single‐Cell Transcriptomics and Metabolomics Reveal Glutamate Dehydrogenase as a Central Regulator of Nitrogen Metabolic Remodeling During Alkalinity Adaptation in Crustaceans
BibTeX
@misc{shanmugaraj2026spatial,
title = {{Spatial metabolomics links polyamine turnover and vascular lipid remodeling to barley spikelet fate}},
author = {N. Shanmugaraj and Y. Huang and A. Garibay-Hernandez and T. Rutten and J. D Auria and H.-P. Mock and T. Schnurbusch},
howpublished = {bioRxiv},
year = {2026},
month = sep,
doi = {10.64898/2026.09.23.753928},
url = {https://www.biorxiv.org/content/10.64898/2026.09.23.753928v1},
note = {CC BY},
}
RIS
TY - UNPB
TI - Spatial metabolomics links polyamine turnover and vascular lipid remodeling to barley spikelet fate
AU - N. Shanmugaraj
AU - Y. Huang
AU - A. Garibay-Hernandez
AU - T. Rutten
AU - J. D Auria
AU - H.-P. Mock
AU - T. Schnurbusch
PY - 2026
DA - 2026/09/23
PB - bioRxiv
DO - 10.64898/2026.09.23.753928
UR - https://www.biorxiv.org/content/10.64898/2026.09.23.753928v1
AB - Local metabolic programs can determine whether developing organs maintain growth, differentiate, or degenerate. However, the spatial establishment of such programs during reproductive development remains poorly understood. In cereal inflorescences, this question is closely tied to grain number because the fate of initiated floral primordia is shaped by the developmental position, metabolic support, genotype, and environmental stress. To understand the metabolic logic underlying floral fate in barley (Hordeum vulgare L.), we mapped the spatial distribution of metabolites across the inflorescence in wild-type Bowman and in hvcmf4, a mutant that undergoes premature apical inflorescence degeneration. Amino acid-, carbohydrate-, and chlorophyll-associated metabolites form clear developmental gradients along the inflorescence axis. These gradients are progressively remodeled during developmental pre-anthesis tip degeneration but are both accelerated and spatially distorted in hvcmf4. Within this broader metabolic landscape, two discrete domains stand out. First, spermidine-associated domains specifically marked reproductive meristems, a pattern corroborated by the meristem-enriched expression of polyamine biosynthetic genes. This polyamine-rich meristem state declined as developmental tip degeneration proceeded and was prematurely lost in hvcmf4, where polyamine metabolism appeared to shift toward oxidative breakdown via the polyamine oxidase pathway. Second, lysophosphatidylcholine accumulated specifically at floral attachment and vascular supply zones. The developmental reduction of this bioactive lysophospholipid-associated domain in the apical regions, and its stronger disruption in hvcmf4, coincided with the reprogramming of lipid-remodeling and auxin transport-associated genes, suggesting impaired coordination of lipid signaling, auxin canalization, and vascular support. Together, our study reveals spatial polyamine and lysophospholipid domains that couple meristem maintenance with vascular support, providing a metabolic framework for the fate of developing cereal inflorescences.
ER -