The synthesis, degradation and biological function of trehalose- 6-phosphate.

Trehalose-6-phosphate (T6P), an intermediate in trehalose metabolic pathways, is ubiquitously present in nearly all cellular organisms except vertebrates. The most well-characterized metabolic route involves its synthesis by trehalose-6-phosphate synthase (TPS) and dephosphorylation to trehalose by trehalose-6-phosphate phosphatase (TPP) in the TPS/TPP pathway. Besides, alternative trehalose metabolic pathways aslo exist. In addition to being the precursor of trehalose synthesis, T6P functions as a signal molecule regulating various biological processes. In plants, T6P inhibits SnRK1 (Sucrose-nonfermenting 1 Related Kinase 1), while in fungi, T6P primarily inhibits hexokinase and regulates glycolysis. Notably, TPS and TPP themselves also have some regulatory functions. Genetic studies reveal that deletion of TPS or TPP usually causes developmental and virulence defects in fungi, bacteria and invertebrates. Given that TPS and TPP have important biological functions in pathogenic fungi but are absent in humans and vertebrates, they are ideal targets for fungicide development. This review summarizes trehalose metabolic pathways and the multifaceted roles of T6P in plants, fungi and invertebrates, providing a comprehensive overview of its biological functions. Additionally, it discusses some reported TPS/TPP inhibitor to offer insights for pathogen control strategies.