Institutional Publications

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

Browse

Author: search.filters.author.Sharma, NamishaSubject: search.filters.subject.Abiotic stress

Search Results

Now showing 1 - 5 of 5
  • Thumbnail Image
    Item
    DNA methylation dynamics in response to abiotic and pathogen stress in plants
    (Springer Nature Publishing AG, 2022) Arora, Heena; Singh, Roshan Kumar; Sharma, Shambhavi; Sharma, Namisha; Panchal, Anurag; Das, Tuhin; Prasad, Ashish; Prasad, Manoj
    DNA methylation is a dynamic epigenetic mechanism that plays a significant role in gene expression and also maintains chromatin stability. The process is conserved in both plants and animals, and crucial for development and stress responses. Differential DNA methylation during adverse environmental conditions or pathogen attack facilitates the selective expression of defense-related genes. Both stress-induced DNA hypomethylation and hypermethylation play beneficial roles in activating the defense response. These DNA marks may be carried to the next generation making the progenies ‘primed’ for abiotic and biotic stress responses. Over the recent years, rapid advancements in the area of high throughput sequencing have enabled the detection of methylation status at genome levels in several plant species. Epigenotyping offers an alternative tool to plant breeders in addition to conventional markers for the selection of the desired offspring. In this review, we briefly discuss the mechanism of DNA methylation, recent understanding of DNA methylation-mediated gene regulation during abiotic and biotic stress responses, and stress memory in plants.
  • Thumbnail Image
    Item
    Role of ubiquitination enzymes in abiotic environmental interactions with plants
    (Elsevier B.V., 2021) Sharma, Shambhavi; Prasad, Ashish; Sharma, Namisha; Prasad, Manoj
    Ubiquitination, a post-translational modification, plays a crucial role in various aspects of plant development and stress responses. Protein degradation by ubiquitination is well established and ubiquitin is the main underlying component directing the turnover of proteins. Recent reports have also revealed the non-proteolytic roles of ubiquitination in plants. In the past decade, ubiquitination has emerged to be one of the most important players in modulating plant's responses to abiotic stresses, which led to identification of specific E3 ligases and their targets involved in the process. Most of the E3 ligases play regulatory roles by modifying the stability and accumulation of stress responsive regulatory proteins, such as transcription factors, thus, modifying the downstream responses, or by degrading the proteins involved in the downstream cascade itself. In this review, we summarize and highlight the recent advances in the field of ubiquitination-mediated regulation of plant's responses to various abiotic stresses including limited nutrient availability and metal toxicity. The non-proteolytic role of ubiquitination in epigenetic regulation of abiotic stress induced response has also been discussed.
  • Thumbnail Image
    Item
    Linking the plant stress responses with RNA helicases
    (Elsevier B.V., 2020) Pandey, Saurabh; Prasad, Ashish; Sharma, Namisha; Prasad, Manoj
    RNA helicases are omnipresent plant proteins across all kingdoms and have been demonstrated to play an essential role in all cellular processes involving nucleic acids. Currently, these proteins emerged as a new tool for plant molecular biologists to modulate plant stress responses. Here, we review the crucial role of RNA helicases triggered by biotic, abiotic, and multiple stress conditions. In this review, the emphasis has been given on the role of these proteins upon viral stress. Further, we have explored RNA helicase mediated regulation of RNA metabolism, starting from ribosome biogenesis to its decay upon stress induction. We also highlighted the cross-talk between RNA helicase, phytohormones, and ROS. Different overexpression and transgenic studies have been provided in the text to indicate the stress tolerance abilities of these proteins.
  • Thumbnail Image
    Item
    Ubiquitination: a tool for plant adaptation to changing environments
    (Springer Nature, 2018) Mandal, Arunava; Sharma, Namisha; Muthamilarasan, Mehanathan; Prasad, Manoj
    Post-translational modifcations namely ubiquitination, phosphorylation, methylation and acetylation play distinct roles in regulating the growth and development of plants. Among these, the ubiquitination regulates the abundance, activities, subcellular compartmentalization and trafcking of regulatory proteins involved in diverse developmental as well as stress-responsive processes. The ubiquitin–proteasome system (UPS) involves fve essential components namely ubiquitin, ubiquitin-activating enzyme (E1), ubiquitin-conjugating enzyme (E2), ubiquitin ligase (E3) and the intact 26S proteasome. The E3 ubiquitin ligase is the major component of UPS that recognizes and tethers poly-ubiquitins on the target proteins. Owing to its specifcity of substrate recognition, the E3 ubiquitin ligase contributes not only to the proteome plasticity of the cell but also regulates the plant’s response to environmental cues. In this context, the review summarizes the components involved in UPS and elaborates the role of E3 ubiquitin ligase in biotic and abiotic stress responses.
  • Thumbnail Image
    Item
    Characterization of DEAD-box family of RNA helicases in tomato provides insights into their roles in biotic and abiotic stresses
    (Elsevier B.V., 2019) Pandey, Saurabh; Muthamilarasan, Mehanathan; Sharma, Namisha; Chaudhry, Vaishali; Dulani, Priya; Shweta, Shweta; Jha, Sarita; Mathur, Saloni; Prasad, Manoj
    In plants, RNA helicases play significant roles in growth, development and stress response. In a previous study, a three-fold upregulation of a DEAD-box RNA helicase in a tomato cultivar tolerant to Tomato leaf curl New Delhi virus (ToLCNDV) as compared to susceptible cultivar during virus infection was shown. Given this, a comprehensive study was performed to identify the members of RNA helicase family in tomato and analyze their functional properties in response to abiotic stresses, hormone treatments and ToLCNDV infection. A total of 131 genes were identified and classified into DEAD- (42), DEAH- (38), and DExD/H-box (51) RNA helicases. Expression profiling of candidate genes in response to abiotic stresses and ToLCNDV infection in contrasting tomato cultivars suggested the putative roles of SlDEAD23 and SlDEAD35 in biotic and abiotic stresses. Heterologous overexpression of these genes in yeast enhanced the tolerance of transgenic cells to salt and cold stresses. Further, virus-induced silencing of SlDEAD35 in ToLCNDV tolerant cultivar resulted in susceptibility to virus infection, thus suggesting its involvement in tolerance mechanism. Altogether, this study provides novel insights into the structure, organization and involvement of DEAD-box RNA helicase genes in biotic and abiotic stress responses in tomato.