GsSLAH3, a Glycine soja slow type anion channel homolog, positively modulates plant bicarbonate stress tolerance

Abstract

Alkaline stress is a major form of abiotic stress that severely inhibits plant growth and development, thus restricting crop productivity. However, little is known about how plants respond to alkali. In this study, a slow-type anion channel homolog 3 gene, GsSLAH3, was isolated and functionally characterized. Bioinformatics analysis showed that the GsSLAH3 protein contains 10 transmembrane helices. Consistently, GsSLAH3 was found to locate on plasma membrane by transient expression in onion epidermal cells. In wild soybeans, GsSLAH3 expression was induced by NaHCO treatment, suggesting its involvement in plant response to alkaline stress. Ectopic expression of GsSLAH3 in yeast increased sensitivity to alkali treatment. Dramatically, overexpression of GsSLAH3 in Arabidopsis thaliana enhanced alkaline tolerance during the germination, seedling and adult stages. More interestingly, we found that transgenic lines also improved plant tolerance to KHCO rather than high pH treatment. A nitrate content analysis of Arabidopsis shoots showed that GsSLAH3 overexpressing lines accumulated more NO than wild-type. In summary, our data suggest that GsSLAH3 is a positive alkali responsive gene that increases bicarbonate resistance specifically.

The Ca2+ Sensor SCaBP3/CBL7 Modulates Plasma Membrane H+-ATPase Activity and Promotes Alkali Tolerance in Arabidopsis

“…The fixation of carbon dioxide in the elongation zone from the bicarbonate buffer leads to the inhibition of root growth (Lee and Woolhouse, 1969). A recent study has reported that a slowtype anion channel homolog in Glycine soja, GsSLAH3, modulates plant bicarbonate stress tolerance (Duan et al, 2018). Heterologous expression of GsSLAH3 in Arabidopsis can increase bicarbonate in shoots, but it does not improve high pH tolerance (Duan et al, 2018).…”

“…A recent study has reported that a slowtype anion channel homolog in Glycine soja, GsSLAH3, modulates plant bicarbonate stress tolerance (Duan et al, 2018). Heterologous expression of GsSLAH3 in Arabidopsis can increase bicarbonate in shoots, but it does not improve high pH tolerance (Duan et al, 2018). Therefore, SCaBP3 may be involved in both extracellular pH and HCO 3 2 responses.…”

Insights into the regulation of wild soybean tolerance to salt-alkaline stress

“…An alkaline stress-induced SLAH gene GsSLAH3 , the homologous gene to AtSLAH3 , was identified in the bicarbonate (NaHCO 3 ) stress tolerant G. soja G07256 based on RNA-seq data. Transgenic Arabidopsis over-expressing GsSLAH3 displayed higher tolerance to stress (NaHCO 3 and KHCO 3 ) rather than high pH stress, by increasing accumulation in shoots ( Duan et al., 2017 ). Consistently, under NaHCO 3 treatment, the concentrations in the T-DNA insertion Arabidopsis mutants atslah3-1 and atslah3-2 were relatively lower than WT ( Zheng et al., 2015 ) ( Figure 1B ).…”

Unfolding molecular switches for salt stress resilience in soybean: recent advances and prospects for salt-tolerant smart plant production

“…In soybean, some genetic factors also regulate NaHCO3 rather than pH. For instance, an alkaline stress-induced slow anion channels homolog (SLAH) GsSLAH3 and B transporters GsBOR2 exerted higher tolerance to NaHCO3 and KHCO3 but not to pH ( Duan et al., 2018a ; Duan et al., 2018b ). However, GsBOR2 direct role in K + regulation under NaHCO3 and KHCO3 stress remained unclear.…”