Comparative Transcriptome Analysis of Two Contrasting Soybean Varieties in Response to Aluminum Toxicity

Abstract

Aluminum (Al) toxicity is a major factor limiting crop productivity on acid soils. Soybean (Glycine max) is an important oil crop and there is great variation in Al tolerance in soybean germplasms. However, only a few Al-tolerance genes have been reported in soybean. Therefore, the purpose of this study was to identify candidate Al tolerance genes by comparative transcriptome analysis of two contrasting soybean varieties in response to Al stress. Two soybean varieties, M90-24 (M) and Pella (P), which showed significant difference in Al tolerance, were used for RNA-seq analysis. We identified a total of 354 Al-tolerance related genes, which showed up-regulated expression by Al in the Al-tolerant soybean variety M and higher transcript levels in M than P under Al stress. These genes were enriched in the Gene Ontology (GO) terms of cellular glucan metabolic process and regulation of transcription. Five out of 11 genes in the enriched GO term of cellular glucan metabolic process encode cellulose synthases, and one cellulose synthase gene (Glyma.02G205800) was identified as the key hub gene by co-expression network analysis. Furthermore, treatment of soybean roots with a cellulose biosynthesis inhibitor decreased the Al tolerance, indicating an important role of cellulose production in soybean tolerance to Al toxicity. This study provides a list of candidate genes for further investigation on Al tolerance mechanisms in soybean.

Metal and Metalloid Toxicity in Plants: An Overview on Molecular Aspects

“…As expected, many of the differentially expressed genes (DEGs) are involved in the antioxidative machinery [ 152 , 154 , 167 , 168 ], transport, [ 151 , 156 , 163 ], and cell wall biosynthesis [ 157 ]; therefore, the expression (constitutive or metal stress induced) of such genes is vital for the plant, mostly in the roots during the first stages of metal stress. The localization of some transporter-like genes within the cell structure (plasma membrane or vacuoles) provides knowledge of which mechanisms are preferred by plants at the molecular level [ 163 , 164 ].…”

“…Another aspect of this type of analysis is the translocation or accumulation of toxic elements within the different complex cell structures that make up plant roots. Furthermore, the use of technologies such as microarrays, RNAseq, and wide genome analysis has increased the amount of transcriptomic and genomic information available for plants under metal stress [ 135 , 151 , 152 , 153 , 154 , 155 , 156 , 157 , 158 , 159 ]. When analyzing the different plant transcriptomes under conditions of metal/metalloid stress, conserved trends have been observed.…”

Transcriptome analysis and functional identification of GmMYB46 in soybean seedlings under salt stress

“…The mixture consisted of 10 µL HieffTM qPCR SYBR ® Green Master Mix (No Rox Plus) (11201ES, Yeasen, Shanghai, China), 0.5 µL (10 µM) Primer F, 0.5 µL (10 µM) Primer R, and 9 µL (100 ng/µL) diluted cDNA. Relative expression of the genes was analyzed with the 2 −ΔΔCt method using the GmEF-1 α gene as an internal control to normalize the level of gene expression ( Zhao et al, 2020 ). The primers for qRT-PCR analysis were designed using the Primer Blast tool on the NCBI ( http://www.ncbi.nlm.nih.gov/ ).…”

Advances in Transcriptome Analyses Using RNA Sequencing Technology in Soybean Plants [Glycine max]

“…Aluminum (Al) toxicity is a major problem on acid soils. Zhao et al (2020) carried out comparative transcriptome analysis of two contrasting soybean varieties in response to Al stress. They identified a total of 354 Al-tolerance related genes, showed up-regulated expression by Al in the Al-tolerant soybean variety.…”