Evolution of Phosphoenolpyruvate carboxylase encoding transcripts in Chickpea (Cicer arietinum L.)

Background: Phosphoenolpyruvate carboxylase (PEPC; EC 4.1.1.31) is an important enzyme encoded by a gene family of at least 2-8 plant type and 1-2 bacterial type genes depending upon genome size or species complexity. This enzyme functions as catalyst for the β-carboxylation of phosphoenolpyruvate (PEP) to form oxaloacetate in cytoplasm. It is involved in carbon fixation and various other plant metabolic pathways.Methods: In this study we characterized the evolutionary perspective of PPC transcripts and their abundance pattern in different plant tissues of chickpea (Cicer arietinum L.).Results: The current study revealed that PEPC enzyme in chickpea is encoded by a gene family of at least 6 transcripts. All active site residues of C3 PEPCs were found in transcripts. Phylogenetic analysis of the amino acid sequences showed two major groups PTPC and BTPC from different ancestral lineages. Divergence of PTPC in two groups and further convergence within species was found in most of the plants while multiple evolutionary divergences was likely to be specific in legumes including chickpea.Conclusion: CaPPC genes are regulated under various abiotic stress. Furthermore, the expression pattern of the identified genes can be helpful to explore plant metabolism of chickpea under abiotic stresses, which can be the next step to explore more into this gene family in chickpea.Keywords: Phosphoenolpyruvate carboxylase transcripts; Chickpea; Phylogen

Involvement of CmWRKY10 in Drought Tolerance of Chrysanthemum through the ABA-Signaling Pathway

Drought is one of the important abiotic factors that adversely affects plant growth and production. The WRKY transcription factor plays a pivotal role in plant growth and development, as well as in the elevation of many abiotic stresses. Among three major groups of the WRKY family, the group IIe WRKY has been the least studied in floral crops. Here, we report functional aspects of group IIe WRKY member, i.e., CmWRKY10 in chrysanthemum involved in drought tolerance. The transactivation assay showed that CmWRKY10 had transcriptional activity in yeast cells and subcellular localization demonstrated that it was localized in nucleus. Our previous study showed that CmWRKY10 could be induced by drought in chrysanthemum. Moreover, the overexpression of CmWRKY10 in transgenic chrysanthemum plants improved tolerance to drought stress compared to wild-type (WT). High expression of DREB1A, DREB2A, CuZnSOD, NCED3A, and NCED3B transcripts in overexpressed plants provided strong evidence that drought tolerance mechanism was associated with abscisic acid (ABA) pathway. In addition, lower accumulation of reactive oxygen species (ROS) and higher enzymatic activity of peroxidase, superoxide dismutase and catalase in CmWRKY10 overexpressed lines than that of WT demonstrates its role in drought tolerance. Together, these findings reveal that CmWRKY10 works as a positive regulator in drought stress by regulating stress-related genes