RRC ID 54606
Author Lee SB, Suh MC.
Title Disruption of glycosylphosphatidylinositol-anchored lipid transfer protein 15 affects seed coat permeability in Arabidopsis.
Journal Plant J
Abstract The hydrophobic biopolymer suberin, which is deposited in the root endodermis and seed coats, functions as an extracellular barrier against uncontrolled water, gas, and ion loss. Suberin monomers synthesized in the endoplasmic reticulum (ER) are exported through the plasma membrane to the apoplast. However, limited information is available about the molecular mechanisms underlying suberin monomer export and assembly. In this study, we investigated the in planta role of LTPG15 encoding a glycosylphosphatidylinositol (GPI)-anchored lipid transfer protein. LTPG15 was predominantly expressed in the root endodermis and seed coat. Fluorescent signals from LTPG15:eYFP were detected in the plasma membrane in tobacco epidermis. Disruption of LTPG15 caused a significant decrease in the levels of fatty acids (C20-C24), primary alcohols (C20 and C22), ω-hydroxy fatty acids (C22 and C24), and α,ω-alkanediols (C20 and C22), but an increase in the amounts of primary alcohols and hydroxy fatty acids with C16 and C18 in seed coats. The mutant phenotype was restored to that of the wild type (WT) by the expression of LTPG15 driven by its own promoter. Seed coats of ltpg15 had an increase in permeability to tetrazolium salts compared with WT seed coats. ltpg15 seeds were more sensitive than WT seeds to inhibition of germination and seedling establishment by salt and osmotic stress treatments. Taken together, our results indicate that LTPG15 is involved in suberin monomer export in seed coats, and this highlights the role of Type G non-specific lipid transfer proteins (LTPGs) in very-long-chain fatty acids and their derivatives' export for suberin polyester formation.
Volume 96(6)
Pages 1206-1217
Published 2018-12-1
DOI 10.1111/tpj.14101
PMID 30242928
MeSH Arabidopsis / genetics Arabidopsis / metabolism* Arabidopsis Proteins / genetics Arabidopsis Proteins / metabolism Arabidopsis Proteins / physiology* Carrier Proteins / physiology* Cell Membrane / metabolism Fatty Acid-Binding Proteins / genetics Fatty Acid-Binding Proteins / metabolism Fatty Acid-Binding Proteins / physiology* Glycosylphosphatidylinositols / metabolism* Permeability Phylogeny Plants, Genetically Modified Seeds / metabolism* Transcriptome
IF 5.726
Times Cited 5
Arabidopsis / Cultured plant cells, genes psh10055