A 14 kDa release factor is involved in GTP‐dependent β‐tubulin folding

FEBS Letters

Fontalba, Ana²  Sanchez, Luis M.¹  Campo, Rafael²  Zabala, Juan C.² 

[1] Departamento de Biologia Funcional, Facultad de Medicina, Universidad de Oviedo, Oviedo, Spain;Departamento de Biologia Molecular, Facultad de Medicina, Universidad de Cantabria, Santander, Spain

关键词: Native electrophoresis: Tubulin folding;    Release factor;    Protein purification;   

DOI  :  10.1016/0014-5793(94)01036-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The tubulin folding pathway is a model system to understand protein folding in the cell. It involves the interaction of several chaperones, including TCP-1 and other as yet uncharacterized factors. Release of tubulin monomers from folding intermediates (C₉₀₀ and C₃₀₀) and their incorporation into tubulin dimers is dependent on GTP hydrolysis, magnesium ions and release factors. In this work, we have purified to homogeneity the protein factor responsible for the release of β-tubulin monomers from C₃₀₀ complexes. It has an apparent molecular mass of 14 kDa (p14) as judged by SDS electrophoresis. The protein behaved as a dimer of about 28 kDa when analyzed by gel filtration chromatography. Furthermore, the p14-dependent release of β-tubulin monomers from C₃₀₀ complexes takes place in the presence of GTP. These results suggest that p14 is a new chaperone that assists in tubulin folding by facilitating the acquisition of the native conformation.

【 授权许可】

Unknown