Institutional Publications

Permanent URI for this collectionhttps://ndkr-library.nipgr.ac.in/handle/123456789/11

Browse

Subject: search.filters.subject.crosstalk

Search Results

Now showing 1 - 5 of 5
  • No Thumbnail Available
    Item
    Deciphering the physiological and molecular functions of phytohormones
    (Elsevier B.V., 2023) Sharma, Manvi; Laxmi, Ashverya
    Plants rely on a diverse set of small molecules called phytohormones for growth, development, and adaptability. Since the discovery of auxin, hormones have been at the frontier of plant biology. Classically, hormone functions and responses were studied using synthetic hormones and analogs. However, the advent of technology, multidisciplinary approaches, and the genome sequencing of the model system of Arabidopsis and rice has dramatically increased our understanding of physiological and molecular mechanisms driving plant hormone actions. In this chapter, we talk about how independent or combined molecular action of phytohormones such as with their signaling components and regulators leads to changes in plant physiology to regulate multiple aspects of plant development, defense, and adaptation. We envisage that such detailed knowledge will allow a far greater understanding of the complex dynamics underlying plant hormone action.
  • Thumbnail Image
    Item
    Jasmonic acid coordinates with light, glucose and auxin signalling in regulating branching angle of Arabidopsis lateral roots
    (John Wiley & Sons, 2022) Sharma, Manvi; Sharma, Mohan; Jamsheer, K. Muhammed; Laxmi, Ashverya
    The role of jasmonates (JAs) in primary root growth and development and in plant response to external stimuli is already known. However, its role in lateral root (LR) development remains to be explored. Our work identified methyl jasmonate (MeJA) as a key phytohormone in determining the branching angle of Arabidopsis LRs. MeJA inclines the LRs to a more vertical orientation, which was dependent on the canonical JAR1-COI1-MYC2,3,4 signalling. Our work also highlights the dual roles of light in governing LR angle. Light signalling enhances JA biosynthesis, leading to erect root architecture; whereas, glucose (Glc) induces wider branching angles. Combining physiological and molecular assays, we revealed that Glc antagonizes the MeJA response via TARGET OF RAPAMYCIN (TOR) signalling. Moreover, physiological assays using auxin mutants, MYC2-mediated transcriptional activation of LAZY2, LAZY4 and auxin biosynthetic gene CYP79B2,and asymmetric distribution of DR5::GFP and PIN2::GFP pinpointed the role of an intact auxin mechanism required by MeJA for vertical growth of LRs. We also demonstrated that light perception and signalling are indispensable for inducing vertical angles by MeJA. Thus, our investigation highlights antagonism between light and Glc signalling and how they interact with JA-auxin signals to optimize the branching angle of LRs.
  • Thumbnail Image
    Item
    Drought attenuates plant defence against bacterial pathogens by suppressing the expression of CBP60g/SARD1 during combined stress
    (John Wiley & Sons, 2022) Choudhary, Aanchal; Senthil-Kumar, Muthappa
    In nature, plants are frequently exposed to drought and bacterial pathogens simultaneously. However, information on how the drought and defence pathways interact and orchestrate global transcriptional regulation is limited. Here, we show that moderate drought stress enhances the susceptibility of Arabidopsis thaliana to Pseudomonas syringae pv. tomato DC3000. Using transcriptome meta-analysis, we found that drought and bacterial stress antagonistically modulate a large set of genes predominantly involved in salicylic acid (SA) and abscisic acid (ABA) signalling networks. We identified that the levels of SA and ABA are dynamically regulated during the course of stress. Importantly, under combined stress, drought through the ABA pathway downregulates the induction of CALMODULIN-BINDING PROTEIN 60g (CBP60g) and SYSTEMIC ACQUIRED RESISTANCE DEFICIENT 1 (SARD1), two transcription factors crucial for SA production upon bacterial infection. We also identified an important role of NPR1-LIKE PROTEIN 3 and 4 (NPR3/4) transcriptional repressors in the drought-mediated negative regulation of CBP60g/SARD1 expression. Using a genetic approach, we show that CBP60g/SARD1 expression is the key determinant of plant defence against bacterial pathogens under combined stress. Thus, these transcription factors act as critical nodes for the crosstalk between drought and bacterial stress signalling under combined stress in plants.
  • Thumbnail Image
    Item
    The versatile role of glucose signalling in regulating growth, development and stress responses in plants
    (Springer Nature Publishing AG, 2020) Saksena, Harshita B.; Sharma, Manvi; Singh, Dhriti; Laxmi, Ashverya
    Sugars as an energy source and a signalling molecule are indispensible for growth, development and stress responses in plants. Among sugars, glucose (Glc) has been identified to perform a key role in regulating various cellular and developmental processes in plants. This comprehensive review highlights the crosstalk of glucose signalling with auxin, cytokinin and brassinosteroid signalling in controlling several aspects of plant development including root growth deviation, root waving and coiling, lateral root emergence, hypocotyl elongation, etc. through a Hexokinase 1 dependent and independent pathway in Arabidopsis. It also provides an insight on the role of Glc-mediated target of rapamycin signalling in modulating various abiotic stresses like nutrient deficiency stress, heat stress, oxidative stress etc. The review also discusses about sugar inducible FCS-Like Zinc Finger genes in modulating SNF1-related protein kinase 1 signalling to coordinate growth and stress responses in plants. Therefore, glucose signalling in concert with diverse signalling pathways and via regulating certain genes contributes to numerous cellular processes to control development and stress responses in plants.
  • Thumbnail Image
    Item
    Mitogen-activated protein kinases in abiotic stress tolerance in crop plants: "-omics" approaches
    (Wiley-VCH Verlag GmbH & Co., 2013) Jaggi, Monika; Gupta, Meetu; Tuteja, Narendra; Sinha, Alok Krishna
    Plants, in order to grow and survive, need to counter a plethora of stresses, both biotic and abiotic. During the process of evolution, plants have developed sophisticated mechanisms to perceive these stresses and transduce them down to the nucleus for appropriate cellular adjustment. Phosphorylation of proteins is one of the important mechanisms for controlling many fundamental cellular processes in all living organisms. A network of mitogen-activated protein kinases (MAPKs) is an evolutionarily conserved phosphorelay cascade among animals, plants, and yeasts that transduces a variety of signals from cell surfaces to the nucleus. This unique protein cascade is also involved in the development and survival of the plants. This cascade consists essentially of three components, a MAPK kinase kinase (MAPKKK), a MAPK kinase (MAPKK), and a MAPK connected to each other by the event of phosphorylation. Signaling through MAP kinase cascade can lead to cellular responses including cell division and differentiation as well as responses to various stresses. In plants, MAP kinases are represented by multigene families and are involved in efficient transmission of specific stimuli and also involved in the regulation of the antioxidant defense system in response to stress signaling. In this chapter, we summarize and investigate the participation of MAPKs as possible mediators of various abiotic stresses in plants. We also focus on recent progress in integrated transcriptomics, proteomics, and metabolomics analyses of MAPK signaling pathway that regulates plant physiological processes during abiotic stress responses. We also deal with the limitations and future prospects of these “-omics” approaches.