A putative tomato inositol polyphosphate 5-phosphatase, Le5PT1, is involved in plant growth and abiotic stress responses

Abstract

Based on sequence similarity to Arabidopsis inositol polyphosphate 5-phosphatases (5PTases) involved in abiotic stress responses and development, four tomato cDNAs (Le5PT1-4) encoding putative 5PTase proteins were identified. The predicted protein sequences of the Le5PTs include conserved catalytic domains required for 5PTase enzyme activity. Le5PT1, 2, and 3 showed high amino acid sequence identity with At5PTase2, At5PTase1 and At5PTase3, and At5PTase5 and At5PTase6, respectively. The expression of Le5PT1 was downregulated soon after initiation of dehydration and salt stress as well as exposure to polyethylene glycol (PEG) and NaCl, but not by exogenous ABA treatment. On the other hand, the expression of Le5PT2 gradually increased with time in all treatments. Transgenic tobacco plants overexpressing Le5PT1 exhibited reduced growth in height, leaf area, and dry weight compared to wild type plants. Transgenic plants also had lower water use efficiency (WUE) than wild type and the downregulation of the drought-responsive gene, NtERD10B. Together these results suggest that Le5PT1 may have a negative role in response to water deficit through the repression of drought-inducible genes that in turn affects plant growth and development.

Natural Variation inBrachypodium distachyonResponses to Combined Abiotic Stresses

“…Five SNPs were significantly associated with shoot area throughout the experiment (Supplemental Figure 7A). Potentially interesting candidate genes known to be involved in abiotic stress responses in plants include a Syntaxin 7 (STX7) t-SNARE domain containing protein (Zhu et al, 2002; Kwon et al, 2020; Chen et al, 2019), an Inositol 5-Phosphate gene (Perera et al, 2008; Burnette et al, 2003; Na and Metzger, 2020; Jia et al, 2019), and a Calmodulin-binding Transcription Activator (CAMTA) (Galon et al, 2010; Pandey et al, 2013; Noman et al, 2021; Yang et al, 2010; Shen et al, 2015). One SNP, found on Chromosome 3 and significantly associated with shoot area in the heat treatment, is located within a gene that codes for a CAMTA transcription factor (TF) (Supplemental Figure 7A).…”

Involvement of DNA methylation in regulating the growth of Arabidopsis thaliana seedling exposed to lanthanum(III) at environmental relevant levels

“…On the other hand, DNA methylation can regulate gene expression and thereby in uence the abundance of trait-speci c genes. For example, the reduction of plant height, leaf number, leaf area, primary root length, lateral root number, and root hair number is due to the overexpression of various genes, including 5PTase (At1g05470) [43,44], CRK28 (At4g21400) [45,46], and SCN1 (At3g07880) [47]. Thus, low-dose La(III) might increase DNA methylation levels, inhibit the expression of these genes, ultimately leading to the observed changes in the growth indices.…”

“…In addition, the increase of DNA methylation levels in underground parts may have increased the lateral root number by reducing the expression of CRK28 [45,46], or it might have increased the lateral root number and decreased the root hair number by changing the distribution of auxin in roots [6]. When the exposure to high-dose La(III) was prolonged to 8.0 d, DNA methylation levels in underground and aboveground parts decreased, potentially causing the overexpression of 5PTase [43,44], CRK28 [45,46], and SCN1 [47], thereby reducing plant height, leaf number (8.0 d), leaf area, primary root length, and root hair number. Simultaneously, the auxin contents might have been reduced in primary roots and increased in lateral roots, which could have further promoted the growth of lateral roots [6].…”

“…We speculate that the main reason for the above phenomena is that DNA methylation levels in underground and aboveground parts increased and decreased simultaneously under high-dose La(III) exposure for 2.0 d, which jointly regulated the plant height and primary root length, and nally left them unchanged. When DNA methylation levels in aboveground parts decreased, they might have decreased the expression level of 5PTase [43,44], which could not change the leaf number and leaf area. In addition, the increase of DNA methylation levels in underground parts may have increased the lateral root number by reducing the expression of CRK28 [45,46], or it might have increased the lateral root number and decreased the root hair number by changing the distribution of auxin in roots [6].…”

Comparative transcriptome profile analysis of rice varieties with different tolerance to zinc deficiency

“…2011). In tomato, Le5PT1 was downregulated soon after initiation of dehydration and salt stress, whereas Le5PT2 was gradually upregulated by dehydration, salt stress and ABA stress (Na & Metzger 2020). It could be speculated that Os5ptase3 occurs in the early stage of the response to Zn deficiency in rice.…”