In silico characterization, molecular phylogeny, and expression profiling of genes encoding legume lectin-like proteins under various abiotic stresses in Arabidopsis thaliana

Abstract

Background Lectin receptor-like kinases (Lec-RLKs), a subfamily of RLKs, have been demonstrated to play an important role in signal transduction from cell wall to the plasma membrane during biotic stresses. Lec-RLKs include legume lectin-like proteins (LLPs), an important group of apoplastic proteins that are expressed in regenerating cell walls and play a role in immune-related responses. However, it is unclear whether LLPs have a function in abiotic stress mitigation and related signaling pathways. Therefore, in this study, we examined the possible role of LLPs in Arabidopsis thaliana (AtLLPs) under various abiotic stresses. Results The study was initiated by analyzing the chromosomal localization, gene structure, protein motif, peptide sequence, phylogeny, evolutionary divergence, and sub-cellular localization of AtLLPs. Furthermore, the expression profiling of these AtLLPs was performed using publicly accessible microarray datasets under various abiotic stresses, which indicated that all AtLLPs were differently expressed in both root and shoot tissues in response to abiotic stresses. The cis-regulatory elements (CREs) analysis in 500 bp promoter sequences of AtLLPs suggested the presence of multiple important CREs implicated for regulating abiotic stress responses, which was further supported by expressional correlation analysis between AtLLPs and their CREs cognate transcription factors (TFs). qRT-PCR analysis of these AtLLPs after 2, 6, and 12 h of cold, high light, oxidative (MV), UV-B, wound, and ozone stress revealed that all AtLLPs displayed differential expression patterns in most of the tested stresses, supporting their roles in abiotic stress response and signaling again. Out of these AtLLPs, AT1g53070 and AT5g03350 appeared to be important players. Furthermore, the mutant line of AT5g03350 exhibited higher levels of ROS than wild type plants till 12 h of exposure to high light, MV, UV-B, and wound, whereas its overexpression line exhibited comparatively lower levels of ROS, indicating a positive role of this gene in abiotic stress response in A. thaliana. Conclusions This study provides basic insights in the involvement of two important representative AtLLPs, AT1g53070 and AT5g03350, in abiotic stress response. However, further research is needed to determine the specific molecular mechanism of these AtLLPs in abiotic stress mitigation and related signaling pathways in A. thaliana.

Reconstruction and analysis of the gene regulatory network for cell wall function in <i>Arabidopsis thaliana</i> L. leaves in response to water deficit

“…In a previous study conducted on 220 microarray samples of A. thaliana available in the GEO, it was also shown that under drought conditions, the AT5G03350 gene, encoding salicylic acid-induced legume lectin-like protein 1, was suppressed 7.9 times (Shaik et al, 2013). It seems to be involved in A. thaliana responses to multiple environmental stresses (including cold, high light, oxidative, ozone, and wound) and SA-mediated processes occurring in the effector-induced immune response (Armijo et al, 2013;Biswas et al, 2022). Due to the unusual structure of the legume lectin domain, proteins of this family may have a wide range of carbohydrate-binding specificity (Sharma et al, 1997), which possibly determines their diverse functions (including involvement in symbiosis, defense mechanisms against bacterial infection, enhanced tolerance against insects, salinity, and stomatal closure) (Van Holle et al, 2017).…”

Free Radicals Mediated Redox Signaling in Plant Stress Tolerance

“…Furthermore, researchers have also mapped the position of corresponding protein genes involved in RSS biosynthesis and observed that the majority of them were present on chromosomes 1, 2, 3, and 5 ( Figure 1 A,B) along with the protein/genes of ROS and RNS biosynthesis in Arabidopsis [ 28 ]. In addition, conserved motif analysis and gene sequence alignments demonstrated that all the reactive species producing enzymes/proteins have a highly conserved arrangement of motifs with varying sequences ( Figure 1 C and Figure 2 A) [ 29 ]. The phylogenetic and gene co-expression analysis ( Figure 2 B,C) of the major reactive species producing enzymes/proteins diverge from one another as they evolve from a common ancestor, and co-expression of the corresponding genes is essential for activating the transcription of stress-responsive genes and transcription factors [ 28 , 29 ].…”

“…In addition, conserved motif analysis and gene sequence alignments demonstrated that all the reactive species producing enzymes/proteins have a highly conserved arrangement of motifs with varying sequences ( Figure 1 C and Figure 2 A) [ 29 ]. The phylogenetic and gene co-expression analysis ( Figure 2 B,C) of the major reactive species producing enzymes/proteins diverge from one another as they evolve from a common ancestor, and co-expression of the corresponding genes is essential for activating the transcription of stress-responsive genes and transcription factors [ 28 , 29 ].…”