Comprehensive physiological and transcriptome analysis reveals the cadmium tolerance mechanism of cadmium tolerance protein 3 in Sedum plumbizincicola

Int J Biol Macromol. 2026 Mar:350:150950. doi: 10.1016/j.ijbiomac.2026.150950. Epub 2026 Feb 16.

Abstract

Sedum plumbizincicola is an efficient cadmium (Cd) hyperaccumulator with strong potential for phytoremediation. Although SpCTP3 has been identified as a key Cd-responsive gene, its functional contribution to Cd tolerance remains partially characterized. Here, SpCTP3-overexpressing (OE) plants displayed increased Cd accumulation, improved growth, and enhanced photochemical efficiency under Cd exposure, providing phenotypic evidence supporting a positive role of SpCTP3 in Cd response. Transcriptomic profiling further indicated that SpCTP3 overexpression modulates pathways related to redox homeostasis and stress signaling. Moreover, we identified a Cd-inducible transcription factor, SpMYB108, that binds to and activates the SpCTP3 promoter. Yeast one-hybrid and dual-luciferase assays confirmed this direct regulatory interaction. Collectively, these results provide integrated phenotypic, transcriptional, and regulatory insights into the role of SpCTP3 in Cd hyperaccumulation.

Keywords: Cd stress; SpCTP3; Transcriptome.

MeSH terms

  • Cadmium* / metabolism
  • Cadmium* / toxicity
  • Gene Expression Profiling*
  • Gene Expression Regulation, Plant / drug effects
  • Plant Proteins* / genetics
  • Plant Proteins* / metabolism
  • Promoter Regions, Genetic
  • Sedum* / drug effects
  • Sedum* / genetics
  • Sedum* / metabolism
  • Sedum* / physiology
  • Transcription Factors / genetics
  • Transcription Factors / metabolism
  • Transcriptome*

Substances

  • Cadmium
  • Plant Proteins
  • Transcription Factors