Keywords
Abstract
Soil salinization is among the most severe abiotic constraints on crop productivity worldwide and is particularly acute in the irrigated lowlands of Central Asia. Plant adaptation to high salinity is coordinated largely at the transcriptional level, and the MYB superfamily — the largest family of transcription factors in Arabidopsis thaliana — has emerged as a recurrent regulatory node in this process. The present work provides an integrative in silico survey of experimentally validated AtMYB genes implicated in the salt stress response, combining a systematic literature analysis with database-driven annotation, promoter cis-element prediction, expression profiling and protein–protein interaction mapping. The curated evidence indicates that MYB factors operate at several distinct levels: modulation of abscisic acid (ABA) signalling through repression of clade A protein phosphatases 2C (AtMYB20, AtMYB44); control of ion homeostasis via the Salt Overly Sensitive (SOS) pathway (AtMYB73); reinforcement of the cuticular and suberin barrier together with antioxidant capacity (AtMYB49); and regulation of photosynthetic performance and reactive oxygen species metabolism under NaCl (MYB37, AtMYB72). Positive and negative regulators co-occur within single phylogenetic subgroups, indicating functional divergence after gene duplication. The analysis outlines a testable model of MYB-mediated salt signalling and identifies priority candidates for functional validation in salt-tolerant crop germplasm.
References
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