A Functional Genomic Perspective on Drought Signalling and its Crosstalk with Phytohormone-mediated Signalling Pathways in Plants

Abstract

Introduction:Drought stress is one of the most important abiotic stresses that negatively influence crop performance and productivity. Plants acclimatize to drought stress conditions through altered molecular, biochemical and physiological responses. Gene and/or protein expression and regulation are thought to be modulated upon stress perception and signal transduction for providing requisite endurance to plants.Plant growth regulators or phytohormones are important molecules required for various biological processes in plants and are also central to stress signalling pathways. Among various phytohormones, Abscisic Acid (ABA) and Ethylene (ET) are considered to be the most vital growth regulators implicated in drought stress signalling and tolerance. Besides the above two known classical phytohormones, Salicylic Acid (SA) and Jasmonic Acid (JA) have also been found to potentially enhance abiotic stress tolerance particularly that of drought, salinity, and heat stress tolerance in plants. Apart from these several other growth regulators such as Cytokinins (CKs), Auxin (AUX), Gibberellic Acid (GA), Brassinosteroids (BRs) and Strigolactones (SLs) have also been reported to actively participate in abiotic stress responses and tolerance in plants. The abiotic stress signalling in plants regulated by these hormones further depends upon the nature, intensity, and duration of exposure to various environmental stresses. It has been reported that all these phytohormones are also involved in extensive crosstalk and signal transduction among themselves and/or with other factors.Conclusion: This review thus summarizes the molecular mechanism of drought signalling and its crosstalk with various phytohormone signalling pathways implicated in abiotic stress response and tolerance.

YUCCA4 overexpression modulates auxin biosynthesis and transport and influences plant growth and development via crosstalk with abscisic acid in Arabidopsis thaliana

“…Taken together, these data reinforce the idea that overall auxin accumulation increases as a consequence of YUC4 overexpression. 35S::YUC4 expression up-regulates the ABI4 transcription factor ABA signaling mediates adaptation to several stressing conditions and also accounts for growth and root architecture modulation (Tiwari et al, 2017). To assess the possible interaction of auxin overproduction in 35S::YUC4 seedlings and ABA signaling, the expression of ABI4::GUS, an ABA-related reporter gene that reflects the endogenous ABI4 transcript level (Bossi et al, 2009;Soderman et al, 2000) was evaluated.…”

“…In addition to its importance towards understanding hormonal-dependent regulation of plant growth and development, how auxin interacts with abscisic acid (ABA) is a question of growing interest owing its role in adaptation to environmental stress (Kim et al, 2013;Ke et al, 2015;Tiwari et al, 2017). ABA regulates embryo and seed development, seed dormancy, germination, senescence, vegeta-tive growth, lateral root development, and drought tolerance (Finkelstein et al, 2002;De Smet et al, 2003).…”

Epigenetic signatures of stress adaptation and flowering regulation in response to extended drought and recovery in Zea mays

“…Plants adopt specific strategies to cope with water scarcity and avoid drastic effect on their grown and development (Chinnusamy & Zhu, ; Zhu, ). Drought induces specific stress signaling pathways, usually related to hormones like abscisic acid (ABA), jasmonic acid (JA) and ethylene, resulting in production of proteins that prevent cellular damage (Tiwari, Lata, Chauhan, Prasad, & Prasad, ). Also regulatory proteins, including transcription and post‐transcription factors, as well as kinases and phosphatases, and signaling molecule levels are altered by water stress (Haak et al, ; Janiak, Kwaśniewski, & Szarejko, ; Nakashima, Yamaguchi‐Shinozaki, & Shinozaki, ).…”

Transcriptome Profiling, Biochemical and Physiological Analyses Provide New Insights towards Drought Tolerance in Nicotiana tabacum L.

“…Some of these changes just represent a consequence of the cell damage, while other show adaptive processes that plants evolved in response to the stressful environmental cues. At a molecular level, plants respond and adapt to drought by inducing both regulatory and functional genes via perception, signal transduction, expression of downstream drought responsive genes network and production of metabolites that protect and maintain the structure of cellular components [14].…”