Genome-Wide Analysis of CCA1-Like Proteins in Soybean and Functional Characterization of GmMYB138a

Abstract

Plant CIRCADIAN CLOCK ASSOCIATED1 (CCA1)-like proteins are a class of single-repeat MYELOBLASTOSIS ONCOGENE (MYB) transcription factors generally featured by a highly conserved motif SHAQK(Y/F)F, which play important roles in multiple biological processes. Soybean is an important grain legume for seed protein and edible vegetable oil. However, essential understandings regarding CCA1-like proteins are very limited in soybean. In this study, 54 CCA1-like proteins were identified by data mining of soybean genome. Phylogenetic analysis indicated that soybean CCA1-like subfamily showed evolutionary conservation and diversification. These CCA1-like genes displayed tissue-specific expression patterns, and analysis of genomic organization and evolution revealed 23 duplicated gene pairs. Among them, GmMYB138a was chosen for further investigation. Our protein–protein interaction studies revealed that GmMYB138a, but not its alternatively spliced isoform, interacts with a 14-3-3 protein (GmSGF14l). Although GmMYB138a was predominately localized in nucleus, the resulting complex of GmMYB138a and GmSGF14l was almost evenly distributed in nucleus and cytoplasm, supporting that 14-3-3s interact with their clients to alter their subcellular localization. Additionally, qPCR analysis suggested that GmMYB138a and GmSGF14l synergistically or antagonistically respond to drought, cold and salt stresses. Our findings will contribute to future research in regard to functions of soybean CCA1-like subfamily, especially regulatory mechanisms of GmMYB138a in response to abiotic stresses.

Revisiting the Role of Plant Transcription Factors in the Battle against Abiotic Stress

“…A CCA1 -like MYB protein, GmMYB138a, interacts with GmSGF14l (a 14-3-3 protein) that alters the subcellular localization of GmMYB138a. qPCR analysis demonstrated that GmMYB138a and GmSGF14l respond synergistically or antagonistically to salt, drought, and cold stresses [ 220 ]. In addition, Jaradat et al [ 206 ] stated that Arabidopsis MYBR1 physically interacts with an ABA receptor protein, PYL8, and directly participates in early ABA signaling.…”

Characterizing the Role of TaWRKY13 in Salt Tolerance

“…These are accompanied by many physiological, biochemical and developmental changes [2]. Current research on plant stress response has reached the level of cells and molecules, and combined with genetics, we can explore the stress responsive mechanisms in order to improve plant growth under conditions of stress [3,4,5,6,7].…”

Identification and characterization of GmMYB118 responses to drought and salt stress

“…The species of MYB-related TF genes were various in different species (Table 1 ). To analyze the entire MYB-related family in soybean, we queried several databases such as Phytozome, TFDB, Pfam, SMART and ScanProsite [ 10 ]. Previous work revealed 127 MYB-related TF genes in soybean [ 28 ]; and these genes were searched against the above websites.…”

“…According to the gene accession number we submitted to the soybase website ( http://soybase.org/soyseq/ ) [ 10 ], we obtained the tissue expression data of quantified prediction for a diverse set of fourteen tissue types (Additional file 1 : Figure S1). It showed that the expression level of several genes in roots, leaf nodes, leaves and flowers was higher than that in seeds and pods.…”

“…The MYB TFs, which represent the largest family in plants, can be divided into different subfamilies depending on the number of adjacent repeats within the MYB domain. Each repeat forms a helix-turn-helix structure of approximately 53 amino acids [ 10 ]. MYB-like proteins with one repeat were considered MYB-related (containing a single or a partial MYB repeat), those with two were regarded as R2R3-type MYBs (2R-MYB), those with three were regarded as R1R2R3-type MYBs (3R-MYBs), and those with four repeats were regarded as 4R-MYBs [ 5 , 9 , 11 – 15 ].…”