Understanding the Role of the WRKY Gene Family under Stress Conditions in Pigeonpea (Cajanus Cajan L.)

Abstract

Pigeonpea (Cajanus cajan L.), a protein-rich legume, is a major food component of the daily diet for residents in semi-arid tropical regions of the word. Pigeonpea is also known for its high level of tolerance against biotic and abiotic stresses. In this regard, understanding the genes involved in stress tolerance has great importance. In the present study, identification, and characterization of WRKY, a large transcription factor gene family involved in numerous biological processes like seed germination, metabolism, plant growth, biotic and abiotic stress responses was performed in pigeonpea. A total of 94 WRKY genes identified in the pigeonpea genome were extensively characterized for gene-structures, localizations, phylogenetic distribution, conserved motif organizations, and functional annotation. Phylogenetic analysis revealed three major groups (I, II, and III) of pigeonpea WRKY genes. Subsequently, expression profiling of 94 CcWRKY genes across different tissues like root, nodule, stem, petiole, petal, sepal, shoot apical meristem (SAM), mature pod, and mature seed retrieved from the available RNAseq data identified tissue-specific WRKY genes with preferential expression in the vegetative and reproductive stages. Gene co-expression networks identified four WRKY genes at the center of maximum interaction which may play a key role in the entire WRKY regulations. Furthermore, quantitative real-time polymerase chain reaction (qRT-PCR) expression analysis of WRKY genes in root and leaf tissue samples from plants under drought and salinity stress identified differentially expressed WRKY genes. The study will be helpful to understand the evolution, regulation, and distribution of the WRKY gene family, and additional exploration for the development of stress tolerance cultivars in pigeonpea and other legumes crops.

Preferential Ribosome Loading on the Stress-Upregulated mRNA Pool Shapes the Selective Translation under Stress Conditions

“…WRKY transcription factor genes, known as the largest gene family in higher plants, have been reported in many species including Arabidopsis , rice, tomato, cotton, pineapple and wild strawberry [ 39 ]. Massive studies have indicated the regulatory role of WRKY gene members that confers biotic as well as abiotic stress tolerance to crop plants [ 40 ]. Heat shock proteins (HSPs), often performing chaperone functions [ 41 ], express not only in response to various stresses [ 42 , 43 , 44 , 45 ], but also exhibit developmental and clinical significances [ 46 , 47 , 48 ].…”

Genetic and Genomic Prospects for Camel Meat Production

“…The WRKY genes play a significant role in regulating several processes in plants (Chen et al, 2012;Yu et al, 2010). The WRKY proteins, based on the WRKY domain numbers and zing-finger pattern/signature have been classified in three groups; group I, group II and group III (Singh et al, 2019;Yu et al, 2010). The WRKY proteins belonging to group I have two domains and a C2H2 zinc-finger signature.…”

Understanding the Effect of Structural Diversity in WRKY Transcription Factors on DNA Binding Efficiency through Molecular Dynamics Simulation

“…In the present study, we selected three WRKY-DBDs representing three different variants that belong to different groups [47]. The CcWRKY1belongedto group I, having two WRKY DBDs, one at N-terminal and another at C-terminal, while only the C-terminal WRKY domain took part in the sequence-specific DNA-binding process, thus the C-terminal domain of CcWRKY1 was considered Type I WRKY-DBD.…”

“…Pigeonpea crop has vital importance in food and nutritional security since it provides a rich source of proteins, vitamins, and minerals for more than a billion of the population in the developing world [45,46]. According to Food and Agriculture Organization [47] statistics, the estimated common cropping area under the pigeonpea cultivation was approximately 7.03 million hectares in 2018 with a production of 4.89 million tons and an average yield of 695Kg/ha. Considering the cropping area and the production of pigeonpea, India ranks first in the world, which accounts for approximately sixty-six percent of total pigeonpea production.…”