1.Identification and verification of key salt-tolerant amino acid sites of banana MaNHX5.
Ya XU ; Mengxin TENG ; Fei QIAO ; Xingyu JIANG ; Yang ZHOU ; Xinguo LI
Chinese Journal of Biotechnology 2022;38(5):1946-1952
In order to improve the salt tolerance of banana NHX genes, we cloned a MaNHX5 gene from Musa acuminata L. AAA group and predicted the key salt-tolerant amino acid sites and mutant protein structure changes of MaNHX5 by using bioinformatics tools. The 276-position serine (S) of MaNHX5 protein was successfully mutated to aspartic acid (D) by site-directed mutagenesis, and the AXT3 salt-sensitive mutant yeast was used for a functional complementation test. The results showed that after the mutated MaNHX5 gene was transferred to AXT3 salt-sensitive mutant yeast, the salt tolerance of the mutant yeast was significantly improved under 200 mmol/L NaCl treatment. It is hypothesized that Ser276 of MaNHX5 protein plays an important role in the transport of Na+ across the tonoplast.
Amino Acids/metabolism*
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Gene Expression Regulation, Plant
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Musa/metabolism*
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Plant Proteins/metabolism*
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Plants, Genetically Modified
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Saccharomyces cerevisiae/metabolism*