Genome-Wide Identification and Analysis of R2R3-MYB Genes Response to Saline–Alkali Stress in Quinoa

Abstract

Soil saline–alkalization inhibits plant growth and development and seriously affects crop yields. Over their long-term evolution, plants have formed complex stress response systems to maintain species continuity. R2R3-MYB transcription factors are one of the largest transcription factor families in plants, widely involved in plant growth and development, metabolism, and stress response. Quinoa (Chenopodium quinoa Willd.), as a crop with high nutritional value, is tolerant to various biotic and abiotic stress. In this study, we identified 65 R2R3-MYB genes in quinoa, which are divided into 26 subfamilies. In addition, we analyzed the evolutionary relationships, protein physicochemical properties, conserved domains and motifs, gene structure, and cis-regulatory elements of CqR2R3-MYB family members. To investigate the roles of CqR2R3-MYB transcription factors in abiotic stress response, we performed transcriptome analysis to figure out the expression file of CqR2R3-MYB genes under saline–alkali stress. The results indicate that the expression of the six CqMYB2R genes was altered significantly in quinoa leaves that had undergone saline–alkali stress. Subcellular localization and transcriptional activation activity analysis revealed that CqMYB2R09, CqMYB2R16, CqMYB2R25, and CqMYB2R62, whose Arabidopsis homologues are involved in salt stress response, are localized in the nucleus and exhibit transcriptional activation activity. Our study provides basic information and effective clues for further functional investigation of CqR2R3-MYB transcription factors in quinoa.

Genome-wide identification of WRKY transcription factors in Casuarina equisetifolia and the function analysis of CeqWRKY11 in response to NaCl/NaHCO3 stresses

“…Further, the distribution of 11 representative cis -acting regulatory elements in promoter regions was investigated. Based on their functions, these cis -acting elements were divided into three categories: category 1 included motifs related to hormone response (ABRE, P-box, TATC-box, TGACG-motif, AuxRR-core, TGA-element), and category 2 had motifs related to environmental stress (WUN-motif, TC-rich repeats, LTR and MBS), while category 3 included motifs related to development (MBSI) [ 32 , 46 , 47 ]. The analysis showed that abundant cis -acting elements were distributed in the promoter regions of CeqWRKYs (Fig.…”

“…More than half of CeqWRKYs contained 3–5 ABRE elements (Fig. 3 B), which play important roles in ABA-mediated diverse stress response in plants [ 47 ]. In addition, 52 CeqWRKYs contained TGACG-motifs that could be related to MeJA response pathway.…”

“…Previous studies showed that WRKY11, WRKY33, WRKY41, and WRKY46 from different plant species play key roles in response to diverse stresses [ 47 – 49 ]. According to the co-expression networks, these four CeqWRKYs may play important roles in response to NaCl and NaHCO 3 stress.…”

“…Furthermore, the distribution of CeqWRKY genes within each group or subgroup was similar to that of A. thaliana and P. trichocarpa [ 1 , 57 ]. Previous study has demonstrated that genes expression and function were highly related to their regulatory elements in promoter [ 47 ]. Our study found that the promoter region of group IIc CeqWRKYs included more stress-related cis -elements (Fig.…”

Molecular Characterization and Expression Analysis of YABBY Genes in Chenopodium quinoa

“…More than 60 TF families are found in plants, and some of them are plant specific [18]. Eleven TF families have been investigated genome-wide in quinoa, including NAC [19], WRKY [20], SPL [21,22], bZIP [5], bHLH [23], trihelix [24], R2R3-MYB [25], BBX [26], ARF [27], VOZ [28], and GRAS [29]. They play vital roles in developmental processes and diverse stress responses.…”