AtTSPO, a translocator protein, in stress responses in Arabidopsis

• TSPO protein in Arabidopsis (AtTSPO) is a translocator protein 18 kDa that is encoded by a single intronless locus.
• It has been shown that AtTSPO is induced by abiotic stresses and plant stress hormone abscisic acid.
• In this review, we summarize the expression pattern, sub-cellular localization, interacting proteins, and biological functions.
• In addition, we discuss the future directions of study on AtTSPO.

Translocator protein 18 kDa (TSPO) contains a structural domain of TspO/PBR, which was previously named peripheral benzodiazepine receptor (PBR). The main biochemical functions of TSPO were reported to be transporting heme, porphyrin, steroid and anion, by which TSPO plays very important roles in the processes of biosynthesis, cellular respiration, cell proliferation and apoptosis in animals. In recent years, the biological functions of TSPOs were documented in plants. TSPO protein in Arabidopsis (AtTSPO) is encoded by a single intronless locus (At2g47770). It has been shown that AtTSPO is induced by abiotic stresses and plant stress hormone abscisic acid (ABA). In this review, we summarize the expression pattern, sub-cellular localization, interacting proteins, and biological functions. In addition, we discuss the future directions of study on AtTSPO.