Cadmium tolerance mediated by GhBCAT12 through branched-chain amino acid degradation via vacuolar sequestration in cotton

Abstract

Soil Cd²⁺ pollution threatens agricultural safety. Branched-chain amino acid (BCAA) metabolism is involved in stress responses, but its role in cotton Cd²⁺ tolerance remains unclear. Here, 16 GhBCAT genes were identified in Gossypium hirsutum, among which GhBCAT12 was significantly induced by Cd²⁺ stress. Silencing GhBCAT12 increased Cd²⁺ sensitivity, causing growth inhibition, oxidative damage, and cell death. Metabolomic analysis revealed the accumulation of leucine, isoleucine, and valine, with decreased acetyl-CoA, indicating that GhBCAT12 mediates BCAA degradation. This study reveals a novel pathway in which GhBCAT12-mediated BCAA degradation provides acetyl-CoA precursors for the tricarboxylic acid (TCA) cycle, sustaining ATP production, which in turn powers vacuolar Cd²⁺ sequestration. These findings provide a new target for improving heavy metal tolerance in crops.

Keywords

Branched-chain amino acids / Cd²⁺ stress / Acetyl-CoA / ATP / Gossypium hirsutum

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Funding

Yuelushan Laboratory Breeding Project(YLS-2025-ZY02058)

The National Key Research and Development Program(2024YFD1200300)

RIGHTS & PERMISSIONS

The Author(s)