CDPK1 from Ginger Promotes Salinity and Drought Stress Tolerance without Yield Penalty by Improving Growth and Photosynthesis in Nicotiana tabacum

Abstract

In plants, transient changes in calcium concentrations of cytosol have been observed during stress conditions like high salt, drought, extreme temperature and mechanical disturbances. Calcium-dependent protein kinases (CDPKs) play important roles in relaying these calcium signatures into downstream effects. In this study, a stress-responsive CDPK gene, ZoCDPK1 was isolated from a stress cDNA generated from ginger using rapid amplification of cDNA ends (RLM-RACE) – PCR technique and characterized its role in stress tolerance. An important aspect seen during the analysis of the deduced protein is a rare coupling between the presence of a nuclear localization sequence in the junction domain and consensus sequence in the EF-hand loops of calmodulin-like domain. ZoCDPK1 is abundantly expressed in rhizome and is rapidly induced by high-salt stress, drought, and jasmonic acid treatment but not by low temperature stress or abscissic acid treatment. The sub-cellular localization of ZoCDPK1-GFP fusion protein was studied in transgenic tobacco epidermal cells using confocal laser scanning microscopy. Over-expression of ginger CDPK1 gene in tobacco conferred tolerance to salinity and drought stress as reflected by the high percentage of seed germination, higher relative water content, expression of stress responsive genes, higher leaf chlorophyll content, increased photosynthetic efficiency and other photosynthetic parameters. In addition, transgenic tobacco subjected to salinity/drought stress exhibited 50% more growth during stress conditions as compared to wild type plant during normal conditions. T3 transgenic plants are able to grow to maturity, flowers early and set viable seeds under continuous salinity or drought stress without yield penalty. The ZoCDPK1 up-regulated the expression levels of stress-related genes RD21A and ERD1 in tobacco plants. These results suggest that ZoCDPK1 functions in the positive regulation of the signaling pathways that are involved in the response to salinity and drought stress in ginger and it is likely operating in a DRE/CRT independent manner.

Overexpression of Artemisia annua sterol C-4 methyl oxidase gene, AaSMO1, enhances total sterols and improves tolerance to dehydration stress in tobacco

“…4b). Similar behavior of transgenic plants expressing transgenes have also been observed and reported earlier (Vivek et al 2013;Sharma et al 2014). Higher chlorophyll retention in transgenic plants indicated lesser damage in the chloroplast and thylakoid structure that may occur due to dehydration.…”

Decrypting Calcium Signaling in Plants: The Kinase Way

“…CDPK from Zingiber offi cinale , ZoCDPK1-GFP fusion protein preferably SRP serine-rich protein, ZFP zinc-fi nger protein, SLAC1 slow anion channel associated 1, KAT1 potassium channel in Arabidopsis thaliana 1, ABF ABRE-binding protein/factor, GR geranylgeranyl reductase, HSP1 heat shock protein 1, PIN7 pin-formed 7, CSP1 CDPK substrate protein 1, CAP1 CDPK adapter protein 1, ADF3 actin depolarizing factor 3, ACP acyl-carrier protein, ABI ABA insensitive, ACS 1-aminocyclopropane-1-carboxylic acid synthase, PAL phenylalanine lyase, RSG repression of shoot growth, Toc33 translocon at the outer envelope membrane of chloroplast protein, Rpn3 regulatory subunit of 26S proteosome, PB1 Phox and Bem1 domain protein, RBOH respiratory burst oxidase or NADPH oxidases, ERG1 elicitor-responsive gene 1, CHL1 chlorate-resistant mutant 1 localized in the nucleus and to a reasonable level in cytosol. Under salinity and drought stress conditions, additional GFP signals were detected in plasma membrane but not in cytosol, fairly indicative of re-localization of ZoCDPK1 in response to stress conditions (Vivek et al 2013 ). OsCPK4 and OsCPK18 were also located in plasma membrane and on mutation of the myristoylation site, relocated to cytoplasm.…”

“…Induced by high salt, drought, and JA; overexpression in tobacco-conferred tolerance to salinity and drought stress Vivek et al ( 2013 ) The table has been sorted according to alphabetical order of species and then by gene name The already complex signaling network turned out to be much more complicated when Uno et al ( 2009 ) identifi ed the interacting partners of AtCPK4 and AtCPK11 (share 95 % similarity) by high-throughput yeast-two hybrid interaction. AtCPK4 interacted with 14 redundant proteins (fi ve most redundant interacting proteins are AtDi19, HSP1, serine-rich protein, zinc-fi nger protein, and AtToc33), and 16 proteins have yielded single hit.…”

A Role for Barley Calcium-Dependent Protein Kinase CPK2a in the Response to Drought

“…Abscisic acid (ABA) is recognized as the most critical hormone in plant responses to water deficit. In addition, many functionally diverse second messengers are involved in drought stress tolerance (Zeng et al, 2015), including calcium and calcium sensors, which are important for signaling and subsequent adaptation to stress conditions (Klimecka and Muszynska, 2007; Kudla et al, 2010; Reddy et al, 2011; Vivek et al, 2013). Plants have evolved several classes of calcium-binding proteins, including calcineurin B-like (CBL), calmodulin (CaM) and calmodulin-related proteins (Cheng et al, 2002; Luan et al, 2002).…”