Enhanced Polar Auxin Transport in Tomato Polycotyledon Mutant Seems to be Related to Glutathione Levels

Abstract

Glutathione-dependent root growth in Arabidopsis is linked to polar auxin transport (PAT). Arabidopsis mutants with reduced glutathione (GSH) levels also show reduced PAT.To gain an insight into the relationship between PAT and GSH level, we analysed tomato polycotyledon mutant, pct1-2, which has enhanced PAT. Microarray analysis of gene expression in pct1-2 mutant revealed underexpression of several genes related to glutamate and glutathione metabolism. In consonance with microarray analysis, enzymatic as well as in-vivo assay revealed higher glutathione level in the early phase of pct1-2 seedling growth than WT.The inhibition of auxin transport by 2,3,5-triiodobenzoic acid (TIBA) reduced both GSH level and PIN1 expression in pct1-2 root tips. The reduction of in vivo GSH accumulation in pct1-2 root tips by buthionine sulfoximine (BSO) stimulated elongation of the short root of pct1-2 mutant akin to TIBA. The rescue of short root phenotype of pct1-2 mutant was restricted to TIBA and BSO. The other auxin transport inhibitors 1-N-naphthylphthalamic acid (NPA), 2-[4-(diethylamino)-2-hydroxybenzoyl] benzoic acid (BUM), 3-chloro-4-hydroxyphenylacetic acid (CHPAA), brefeldin and gravacin inhibited root elongation in both WT and pct1-2 mutant.Our results indicate a relationship between PAT and GSH level in tomato akin to Arabidopsis.Our work also highlights that TIBA rescues short root phenotype of the pct1-2 mutant by acting on a PAT component distinct from the site of action of other PAT inhibitors.

Glutathione Enhances Auxin Sensitivity in Arabidopsis Roots

“…Despite the positive role of GSH in cell proliferation, which has been well established in several investigations, GSH had a negative effect on root growth [20,29,83]. By contrast, other studies have shown that GSH stimulated root growth, especially during root growth recovery following the simultaneous application of heavy metals [84]. This discrepancy might be related to an indirect effect of GSH on the pH of the nutrient medium.…”

Transcriptome and Proteomics Analysis of Wheat Seedling Roots Reveals That Increasing NH4+/NO3– Ratio Induced Root Lignification and Reduced Nitrogen Utilization

“…According to the results of our proteome analysis, two shared upregulated proteins (A0A3B6K9P2 and Q8RW00) were GSTs. Previous studies reported that GSTs regulate root development by participating in auxin binding or transport ( Jiang et al, 2010 ; Nongmaithem et al, 2021 ). GSTs also possess glutathione peroxidase activity, quench ROS with the addition of glutathione, and protect the cell from oxidative damage ( Halušková et al, 2009 ; Kumar and Trivedi, 2018 ).…”

High efficient de novo root-to-shoot organogenesis in Citrus jambhiri Lush.: Gene expression, genetic stability and virus indexing

“…Nitsch vitamins are comprised of folic acid (0.5 mg L -1 ) and d-biotin (0.05 mg L -1 ) along with nicotinic acid (5 mg L -1 ), pyridoxine HCl (0.5 mg L -1 ), thiamine HCl (0.5 mg L -1 ), and glycine (2 mg L -1 ), which help in plant organogenesis in combination with various cytokinins and gibberellins. Moreover, plant growth regulators (PGRs) and vitamins in the basal medium play an important role in the onset of dormancy and determination of shoot and root architecture [ 17 ]. Auxins such as NAA, IAA, and indole-3-butyric acid (IBA) play an essential role in root modulation for better adaptation [ 18 ] of in vitro plants.…”

“…Auxins such as NAA, IAA, and indole-3-butyric acid (IBA) play an essential role in root modulation for better adaptation [ 18 ] of in vitro plants. The directional mobility of cytokinins and auxins in plants regulates several biological pathways and regulatory networks [ 17 ].…”