SiMYB56 Confers Drought Stress Tolerance in Transgenic Rice by Regulating Lignin Biosynthesis and ABA Signaling Pathway

Patel

et al. 2021

IJMS

104

Metabolic regulation is the key mechanism implicated in plants maintaining cell osmotic potential under drought stress. Understanding drought stress tolerance in plants will have a significant impact on food security in the face of increasingly harsh climatic conditions. Plant primary and secondary metabolites and metabolic genes are key factors in drought tolerance through their involvement in diverse metabolic pathways. Physio-biochemical and molecular strategies involved in plant tolerance mechanisms could be exploited to increase plant survival under drought stress. This review summarizes the most updated findings on primary and secondary metabolites involved in drought stress. We also examine the application of useful metabolic genes and their molecular responses to drought tolerance in plants and discuss possible strategies to help plants to counteract unfavorable drought periods.

Section: Phenolicsmentioning

confidence: 99%

Metabolomics and Molecular Approaches Reveal Drought Stress Tolerance in Plants

Patel

et al. 2021

IJMS

104

“…It shows that the relevant physiological indicators of MYB in the process of resisting cold stress response are still relatively limited, which is not conducive to exploring the regulatory relationship between MYB and cold stress. MYB TFs are also known to affect signal transduction and phytohormone biosynthesis, including auxin (Wang, Cao & Hao, 2014), gibberellic acid (Aya et al, 2009), methyl jasmonate (Liu et al, 2019;Zhang et al, 2018), andABA (Chen et al, 2020;Xu et al, 2020;Yin et al, 2017). MYB TFs are also involved in the synthesis of plant cell walls, thereby mediating the growth and development of plant cells (Liao et al, 2008;Liu, Osbourn & Ma, 2015).…”

Section: Discussionmentioning

confidence: 99%

Meta-analysis of the effect of expression of MYB transcription factor genes on abiotic stress

Han

Shang

Shao

et al. 2021

PeerJ

Background MYB proteins are a large group of transcription factors. The overexpression of MYB genes has been reported to improve abiotic stress tolerance in plant. However, due to the variety of plant species studied and the types of gene donors/recipients, along with different experimental conditions, it is difficult to interpret the roles of MYB in abiotic stress tolerance from published data. Methods Using meta-analysis approach, we investigated the plant characteristics involved in cold, drought, and salt stress in MYB-overexpressing plants and analyzed the degrees of influence on plant performance by experimental variables. Results The results show that two of the four measured plant parameters in cold-stressed plants, two of the six in drought-stressed, and four of the 13 in salt-stressed were significantly impacted by MYB overexpression by 22% or more, and the treatment medium, donor/recipient species, and donor type significantly influence the effects of MYB-overexpression on drought stress tolerance. Also, the donor/recipient species, donor type, and stress duration all significantly affected the extent of MYB-mediated salt stress tolerance. In summary, this study compiles and analyzes the data across studies to help us understand the complex interactions that dictate the efficacy of heterologous MYB expression designed for improved abiotic stress tolerance in plants.

“…The altered levels of caffeoylquinic acid, an intermediate in the lignin biosynthesis pathway (e Silva, Mazzafera and Cesarino, 2019), and suberin, an effective apoplastic barrier (Vishwanath, Delude, Domergue and Rowland, 2015), seems to be related to cell wall strengthening in response to hardness. Under abiotic stress, lignin accumulation is induced, and its polymers are deposited in cell walls (Srivastava, Vishwakarma, Arafat, Gupta and Khan, 2015; Xu et al, 2020). The increased level of suberin with hardness is consistent with other stress-induced suberization such as salt and drought stress (Byrt, Munns, Burton, Gilliham and Wege, 2018; Krishnamurthy et al, 2009, Krishnamurthy, Ranathunge, Nayak, Schreiber and Mathew 2011).…”

Section: Discussionmentioning

confidence: 99%

Tomato roots sense horizontal/vertical mechanical impedance and divergently modulate root/shoot metabolome

Kumari

Nongmaithem

Devulapalli

et al. 2021

Preprint

Plant roots encounter coarse environs right after emergence from the seeds. Little is known about metabolic changes enabling roots to overcome the soil impedance. Tomato seedlings grown vertically or horizontally, at increasing hardness, exhibited lateral roots proliferation, shorter hypocotyls, and primary roots. In primary root tips, hardness-elicited loss of amyloplasts staining; induced ROS and NO accumulation. The levels of IBA, zeatin, jasmonates, and salicylic acids markedly differed in roots and shoots exposed to increasing hardness. Hardness lowered IAA and elevated ABA levels, while increased ethylene emission was confined to horizontally-impeded seedlings. The trajectories of metabolomic shifts distinctly differed between vertically/horizontally-impeded roots/shoots. In horizontal roots, amino acids were the major affected group, while in vertical roots, sugars were the major group. Commonly affected metabolites in roots and shoots, trehalose, dopamine, caffeoylquinic acid, and suberic acid, hallmarked the signature for hardness. Increasing hardness lowered SnRK1a expression in roots/shoots implying regulation of metabolic homeostasis by the SnRK1 signalling module. Our data suggest that though hardness is a common denominator, roots sense the horizontal/vertical orientation and correspondingly modulate metabolite profiles.Significance statementWe show that the tomato roots sense the magnitude of hardness as well as the horizontal and vertical orientation. The hardness divergently modulates the phytohormone and metabolite levels in roots and shoots. The trajectory of the metabolic shift in vertically-grown seedling distinctly differs from horizontally-grown seedlings. ABA and trehalose were the hallmark of hardness stress and may influence metabolic alteration via the SNRK signalling pathway.