The β-tubulin monomer release factor (p14) has homology with a region of the DnaJ protein

p14 is a molecular chaperone involved in β-tubulin folding which catalyzes the release of β-tubulin monomers from intermediate complexes. Here we demonstrate that active p14 protein which we have purified from an overproducing Escherichia coli strain can also release β-tubulin monomers from tubulin...

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Detalles Bibliográficos
Autores: Llosa, Matxalen, Aloria, Kerman, Campo, Rafael, Padilla, Rodolfo, Ávila, Jesús, Sánchez-Pulido, Luis, Zabala, Juan Carlos
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:1996
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/93208
Acceso en línea:http://hdl.handle.net/10261/93208
Access Level:acceso abierto
Palabra clave:J-domain
p14
β-Tubulin
α-Tubulin
Protein folding
Molecular chaperone
Descripción
Sumario:p14 is a molecular chaperone involved in β-tubulin folding which catalyzes the release of β-tubulin monomers from intermediate complexes. Here we demonstrate that active p14 protein which we have purified from an overproducing Escherichia coli strain can also release β-tubulin monomers from tubulin dimers in the presence of an additional cofactor (Z). Analysis of p14 secondary structure suggests that this protein may belong to a family of conserved proteins which share structural similarities with the J-domain of DnaJ. We have constructed deletions and site-directed mutations in the p14 gene. A single D to E mutation in the region shown in DnaJ to be an essential loop for its function affected the monomer-release activity of p14. These results support the hypothesis that this p14 loop interacts with β-tubulin in a similar fashion as DnaJ interacts with DnaK and suggest a possible role of p14 in the folding process.