Uncovering the Salt Response of Soybean by Unraveling Its Wild and Cultivated Functional Genomes Using Tag Sequencing

Abstract

Soil salinity has very adverse effects on growth and yield of crop plants. Several salt tolerant wild accessions and cultivars are reported in soybean. Functional genomes of salt tolerant Glycine soja and a salt sensitive genotype of Glycine max were investigated to understand the mechanism of salt tolerance in soybean. For this purpose, four libraries were constructed for Tag sequencing on Illumina platform. We identify around 490 salt responsive genes which included a number of transcription factors, signaling proteins, translation factors and structural genes like transporters, multidrug resistance proteins, antiporters, chaperons, aquaporins etc. The gene expression levels and ratio of up/down-regulated genes was greater in tolerant plants. Translation related genes remained stable or showed slightly higher expression in tolerant plants under salinity stress. Further analyses of sequenced data and the annotations for gene ontology and pathways indicated that soybean adapts to salt stress through ABA biosynthesis and regulation of translation and signal transduction of structural genes. Manipulation of these pathways may mitigate the effect of salt stress thus enhancing salt tolerance.

Abiotic Stress Responses in Legumes: Strategies Used to Cope with Environmental Challenges

“…In soybean roots, a digital gene expression profile experiment highlighted a higher ratio of up/down-regulated genes in the salttolerant G. soja than in a salt-sensitive genotype of G. max (Ali et al, 2012). In this study, 490 salt-responsive genes involved in the control of different steps of the salt regulatory pathway including many transcription factors were identified.…”

Catalytic features and crystal structure of a tau class glutathione transferase from Glycine max specifically upregulated in response to soybean mosaic virus infections

“…On the other hand, the enzyme is down regulated by abiotic stress (salt stress, NaCl) as demonstrated using proteomic analysis [28]. It is noteworthy that GmGSTU10-10 gene was found to be constitutively expressed in soybean, suggesting that the enzyme has housekeeping roles and presumably is involved in endogenous developmental processes of soybean [29].…”

Transcriptome Analysis of Canola (Brassica napus) under Salt Stress at the Germination Stage

“…(2005) cloned a major quantitative trait locus encoding a high-affinity K + transporter (HKT)-type sodium transporter that recycles the Na + from the shoots to the roots [ 6 ]. Another group of salt-response genes includes transcription factors (TFs), such as ERF and WRKY, and signal-related protein kinases [ 7 ]. By combining the interaction mode among the mentioned genes above, several pathways that potentiate the salt-stress signal have been revealed, such as the salt overly sensitive (SOS) pathway [ 8 – 9 ], the calcium-dependent protein kinase (CDPK) pathway [ 10 ] and the mitogen-activated protein kinase (MAPK) pathway [ 11 ].…”