The WD40 gene family in recretohalophyte Limonium bicolor: genomic identification and functional analysis in salt gland development and salinity tolerance

TL;DR

This study explores salt tolerance in Limonium bicolor by analyzing WD40 genes linked to salt gland development and stress response.

Contribution

The study identifies specific WD40 genes in Limonium bicolor involved in salt gland development and salinity tolerance.

Findings

Lb1G05968 and Lb3G17197 are key WD40 genes involved in salt gland development.

VIGS experiments showed these genes are crucial for salinity tolerance.

Subfamily 6 is the largest WD40 gene group in L. bicolor.

Abstract

Developing salt-tolerant crops is critical for utilizing saline soils in agriculture. Limonium bicolor, a recretohalophyte with epidermal salt glands, represents a valuable genetic resource for salt tolerance engineering. Although WD40 proteins are known regulators of plant stress responses, their roles in L. bicolor remain unexplored.

We performed a genome-wide analysis of WD40 genes in L. bicolor, including phylogenetic classification, subcellular localization prediction, cis-element analysis, and expression profiling during salt stress. Functional validation was conducted using virus-induced gene silencing (VIGS).

Among 367 identified WD40 genes (distributed across all chromosomes), Subfamily 6 was the largest. Two key members (Lb1G05968 and Lb3G17197, localized in cytoplasm) showed significant involvement in salt gland development and stress tolerance, as demonstrated by VIGS-induced phenotypic defects.

Our findings reveal the WD40 family's expansion in L. bicolor and its functional specialization in salt adaptation. The identified genes (e.g., Lb1G05968, Lb3G17197) provide targets for engineering salt-tolerant crops. This study establishes a foundation for further research on halophyte developmental genetics.

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