Browsing by Author "Chauhan, Harsh"

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Identification and characterization of high temperature stress responsive genes in bread wheat (Triticum aestivum L.) and their regulation at various stages of development
    (Springer Science, 2011) Chauhan, Harsh; Khurana, Neetika; Tyagi, Akhilesh K.; Khurana, Jitendra P.; Khurana, Paramjit
    To elucidate the effect of high temperature, wheat plants (Triticum aestivum cv. CPAN 1676) were given heat shock at 37 and 42°C for 2 h, and responsive genes were identified through PCR-Select Subtraction technology. Four subtractive cDNA libraries, including three forward and one reverse subtraction, were constructed from three different developmental stages. A total of 5,500 ESTs were generated and 3,516 high quality ESTs submitted to Genbank. More than one-third of the ESTs generated fall in unknown/no hit category upon homology search through BLAST analysis. Differential expression was confirmed by cDNA macroarray and by northern/RT-PCR analysis. Expression analysis of wheat plants subjected to high temperature stress, after 1 and 4 days of recovery, showed fast recovery in seedling tissue. However, even after 4 days, recovery was negligible in the developing seed tissue after 2 h of heat stress. Ten selected genes were analyzed in further detail including one unknown protein and a new heat shock factor, by quantitative real-time PCR in an array of 35 different wheat tissues representing major developmental stages as well as different abiotic stresses. Tissue specificity was examined along with cross talk with other abiotic stresses and putative signalling molecules.
  • Thumbnail Image
    Item
    PRpnp, a novel dual activity PNP family protein improves plant vigor and confers multiple stress tolerance in Citrus aurantifolia
    (John Wiley & Sons, 2023) Singh, Sweta; Chaudhary, Chanderkant; Bharsakale, Rushikesh D.; Gazal, Snehi; Verma, Lokesh; Tarannum, Zeba; Behere, G.T.; Giri, Jitender; Germain, Hugo; Ghosh, Dilip K; Sharma, Ashwani K; Chauhan, Harsh
    Under field conditions, plants are often simultaneously exposed to several abiotic and biotic stresses resulting in significant reductions in growth and yield; thus, developing a multi-stress tolerant variety is imperative. Previously, we reported the neofunctionalization of a novel PNP family protein, Putranjiva roxburghii purine nucleoside phosphorylase (PRpnp) to trypsin inhibitor to cater to the needs of plant defense. However, to date, no study has revealed the potential role and mechanism of either member of this protein group in plant defense. Here, we overexpressed PRpnp in Citrus aurantifolia which showed nuclear-cytoplasmic localization, where it functions in maintaining the intracellular purine reservoir. Overexpression of PRpnp significantly enhanced tolerance to salt, oxidative stress, alkaline pH, drought, and two pests, Papilio demoleus and Scirtothrips citri in transgenic plants. Global gene expression studies revealed that PRpnp overexpression up-regulated differentially expressed genes (DEGs) related to ABA- and JA- biosynthesis and signaling, plant defense, growth, and development. LC-MS/MS analysis validated higher endogenous ABA and JA accumulation in transgenic plants. Taken together, our results suggest that PRpnp functions by enhancing the endogenous ABA and JA, which interact synergistically and it also inhibits trypsin proteases in the insect gut. Also, like other purine salvage genes, PRpnp also regulates CK metabolism and increases the levels of CK-free bases in transgenic Mexican lime. We also suggest that PRpnp can be used as a potential candidate to develop new varieties with improved plant vigor and enhanced multiple stress resistance.