Uncovering the role of wheat magnesium transporter family genes in abiotic responses

Abstract

Background: The CorA / MGT / MRS2 family proteins are an important group of magnesium transporter proteins that maintain magnesium ion homeostasis in plant cells. However, little is known about the MGT functions in wheat.

Methods: The known MGT sequences were used as queries to BlastP against wheat genome IWGSC RefSeq v2.1 assembly (E-value <10-5). Chromosome localization information for each TaMGT gene was obtained from the GFF3 file of the wheat genome data (IWGSCv2.1).The sequence of 1500 bp upstream of the TaMGT genes was extracted from the wheat genome data. The cis-elements were analyzed using PlantCARE online tool.

Result: A total of 24 MGT genes were identified on 18 chromosomes of wheat. After functional domain analysis, only TaMGT1A, TaMGT1B, and TaMGT1D had GMN mutations to AMN, while all the other genes had conserved GMN tripeptide motifs. Expression profiling showed that the TaMGT genes were differentially expressed under different stresses and at different growth and development stages. The expression levels of TaMGT4B and TaMGT4A were significantly up-regulated in cold damage. In addition, qRT-PCR results also confirmed that these TaMGT genes are involved in the wheat abiotic stress responses.

Conclusion: In conclusion, The results of our research provide a theoretical basis for further research on the function of TaMGT gene family in wheat.

Keywords: TaMGT; abiotic stresses; climate-resilience; fluorescence quantitative PCR; gene expression; gene structure.

Figure 1

Multiple sequence alignment of TaMGTs. Multiple alignments were performed using DNAMAN software. TM domains are marked with orange lines. Conserved GMN motif is indicated by Red box.

Figure 2

Phylogenetic analysis of Arabidopsis, rice, maize and wheat CorA/MRS2/MGT members. Phylogenetic trees were constructed by the neighbor-Joining method (NJ) using MEGA software for 24 TaMGT proteins, 11 Arabidopsis MRS2/MGT proteins, 9 rice proteins, and 12 maize proteins.

Figure 3

Phylogenetic relationships (A), motif analysis (B) and gene structure (C) of TaMGT family members.

Figure 4

Chromosomal localization and gene duplication of TaMGTs genes. (A) Location of TaMGTs genes on chromosomes, with black representing chromosomes. (B) Gene duplication events in the wheat MGT gene family, where the curves represent gene duplication between chromosomes; the collinearity genes on chromosome 3A, 3B, 3C are highlighted with red lines. (C) Collinearity analysis of wheat with Arabidopsis thaliana and Triticum urartu. The gray line in the background indicates a collinear block in the genome of wheat and Arabidopsis thaliana and Triticum urartu, while the red line highlights the homologous MGT gene pair.

Figure 5

Cis-acting elements analysis of TaMGT genes.

Figure 6

(A) different growth and developmental stages expression analysis (B) different tissues expression analysis (C) abiotic stresses expression analysis (D) biotic stresses expression analysis.

Figure 7

Expression patterns of five TaMGT genes under three different treatments. Three groups of treatments included 60uM aluminum chloride, 100 mmol/L ABA treatment, and magnesium deficiency treatment. The Y-axis represents the relative expression level, and the X-axis represents the time point of treatment. Significant differences at P<0.05 are indicated by letters. The expression levels of TaMGT genes were mapped using Origin software.