Translationally-controlled tumor protein

Translationally-controlled tumor protein (TCTP; encoded by TPT1) is a 172-amino-acid calcium-binding protein involved in microtubule stabilization and regulation of apoptosis (UniProt: P13693). The protein functions as a negative regulator of apoptosis through interaction with and destabilization of TSC22D1, thereby protecting cells from programmed cell death (UniProt: P13693).

TCTP is expressed across multiple tissues and subcellular compartments. While no diseases are explicitly listed in the UniProt record for this protein, it has been investigated in Alzheimer's Disease pathology given its roles in calcium signaling and cytoskeletal dynamics, both implicated in neurodegeneration.

Regarding Alzheimer's Disease relevance, TPT1 shows ambiguous directionality across subcellular fractions in post-mortem AD brain tissue compared to age-matched controls, based on TMT-labeled quantitative proteomics (Chaparral AD proteomics). The mean log2 fold-change is 0.3119 across two analyzed fractions, indicating minimal overall change but with potentially opposing directions in different cellular compartments.