Evolutionary and functional analysis of two‐component system in chickpea reveals CaRR13, a TypeB RR, as positive regulator of symbiosis

Abstract

Summary The critical role of cytokinin in early nodulation in legumes is well known. In our study, exogenous cytokinin application to roots of the important crop legume, chickpea (Cicer arietinum L.), led to the formation of pseudo‐nodules even in the absence of rhizobia. Hence, a genome‐wide analysis of the cytokinin signalling, two‐component system (TCS) genes, was conducted in chickpea, Medicago and Cajanus cajan. The integrated phylogenetic, evolutionary and expression analysis of the TCS genes was carried out, which revealed that histidine kinases (HKs) were highly conserved, whereas there was diversification leading to neofunctionalization at the level of response regulators (RRs) especially the TypeB RRs. Further, the functional role of the CaHKs in nodulation was established by complementation of the sln1Δ mutant of yeast and cre1 mutants of (Medicago) which led to restoration of the nodule‐deficient phenotype. Additionally, the highest expressing TypeB RR of chickpea, CaRR13, was functionally characterized. Its localization in the nucleus and its Y1H assay‐based interaction with the promoter of the early nodulation gene CaNSP2 indicated its role as a transcription factor regulating early nodulation. Overexpression, RNAi lines and complementation of cre1 mutants with CaRR13 revealed its critical involvement as an important signalling molecule regulating early events of nodule organogenesis in chickpea.

Two-Component System Genes in Sorghum bicolor: Genome-Wide Identification and Expression Profiling in Response to Environmental Stresses

“…Conversely, various clades were revealed based on the phylogeny of RRs. Some members from one species clustered on same clade, while members of other plants clustered on another clade, such as the O. sativa clade (Type-B RRs), A. thaliana clade (Type-B3 RRs), and legume-specific clade (Type-B RRs) ( Tiwari et al, 2021 ).…”

“…The HP family contains a domain called the phosphotransfer (Hpt) domain which is essential for transferring a phosphate group from the Rec domain of HKs to the Rec domain of RRs, enabled due to the presence of a highly conserved motif (XHQXKGSSXS) ( Gupta et al, 2020 ; He et al, 2020 ; Tiwari et al, 2021 ). The AHP1 – AHP5 are the five A. thaliana genes that encode the intermediate proteins with an Hpt domain.…”

Effective Use of Water in Crop Plants in Dryland Agriculture: Implications of Reactive Oxygen Species and Antioxidative System

“…The intricate interaction between ROS and these signaling cues orchestrate a cardinal response involving an appropriate molecular, metabolic, and physiological acclimation responses, allowing the plant to survive under adverse environmental conditions ( Zhu et al, 2016 ; Waszczak et al, 2018 ; Kollist et al, 2019 ; Zandalinas et al, 2020 ). The cell division and expansion are critical events of the plant growth process that are often affected by environmental stresses and are under the control of ROS, phytohormones, transcription factors, kinases, and small RNAs ( Huang et al, 2019 ; Mishra et al, 2021b ; Tiwari et al, 2021a , b , c ). The role of ROS in cell proliferation is also evident from reports that reveal manganese superoxide dismutase (MnSOD) regulating a redox cycle within the cell cycle ( Sarsour et al, 2014 ).…”

Omics Path to Increasing Productivity in Less-Studied Crops Under Changing Climate—Lentil a Case Study

“…1 The draft assembly consists of seven pseudomolecules having a size of 4.3 Gb ( Bett et al, 2016 ). This genomic resource can be utilized in lentil breeding programs to identify markers linked to agronomic traits and several important gene families that are widely explored in other plant species ( Mishra et al, 2021b ; Tiwari et al, 2021b , d ). Overall, genomic resources have helped in lentil improvement through genetic finger printing and diversity analysis ( Hamwieh et al, 2009 ; Kumar et al, 2014 ) and the determination of hybrid status of the crosses between diverse parents ( Solanki et al, 2010 ).…”