Background: Abscisic acid (ABA)-, stress- and ripening-induced protein (ASR) is plant-specific hydrophilic transcriptional
regulators involved in sucrose stress and wounding in banana. However, it is not known whether banana
ASR genes confer
salt stress tolerance. The contexts of the studywas to analysis the sequence characterization of banana
ASR1, and identify
its expression patterns and function under salt stress using quantitative real-time PCR (qPCR) and overexpression in
Arabidopsis
. The purpose was to evaluate the role of banana
ASR1 to salt stress tolerance employed by plants.
Results: A full-length cDNA isolated from banana fruitwas named
MaASR1, and it had a 432 bp open reading frame (ORF)
encoding 143 amino acids.
MaASR1 was preferential expression in roots and leaves compared to low expression in fruits,
rhizomes and flowers. Under salt stress, the expression of
MaASR1 quickly increased and highest expression level was
detected in roots and leaves at 4 h, and then gradually decreased. These results suggested that
MaASR1 expression was
induced under salt stress. MaASR1 protein was localized in the nucleus and plasma membrane.
MaASR1 was
transformed to
Arabidopsis and verified by southern and northern analysis, transgenic lines L14 and L38 integrated one
and two copies of
MaASR1, respectively, while overexpression in transgenic lines provided evidence for the role of
MaASR1 to salt stress tolerance.
Conclusions: This study demonstrated that overexpression of
MaASR1 in
Arabidopsis confers salt stress tolerance by
reducing the expression of ABA/stress-responsive genes, but does not affect the expression of the ABA-independent
pathway and biosynthesis pathway genes.
