Genome-Wide Identification of SWEET Gene Family and Integrative Transcriptomic–Metabolomic Analysis Reveal Sugar Transport-Mediated Chilling Responses in Sesame (Sesamum indicum L.)

TL;DR

This study identifies SWEET genes in sesame and shows they help the plant respond to cold stress by transporting sugars.

Contribution

The study reveals the role of SWEET genes in sesame's chilling response through integrated transcriptomic and metabolomic analysis.

Findings

24 SWEET genes were identified and grouped into six conserved families in sesame.

SiSWEET genes correlated with sugar accumulation in cold-tolerant sesame accessions.

SWEET-mediated sugar transport is implicated in sesame's chilling stress response.

Abstract

Sesame is a thermophilic oilseed crop that is vulnerable to low-temperature stress. SWEET sugar transporters are important for sugar allocation, but their roles in sesame cold responses remain poorly understood. In this study, 24 SWEET genes were identified in the sesame genome and classified into six conserved groups with high structural conservation and limited duplication. Comparative transcriptomic and metabolomic analyses of cold-tolerant and cold-sensitive sesame accessions under chilling stress revealed distinct SiSWEET expression patterns and contrasting soluble sugar accumulation. Several SiSWEET genes showed significant correlations with glucose, fructose, and sucrose contents. These results suggest that SWEET-mediated sugar transport is involved in sesame chilling responses and provide candidate genes for improving cold tolerance.

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