Characterization of the regulatory subunit of Yarrowia lipolytica cAMP - dependent protein kinase evidences of a monomeric protein

cAMP-dependent protein kinase [PKA] catalytic [C] and regulatory [R] subunits from Yarrowia lipolytica are encoded by single genes, TPK1 and RKA1, respectively. Here we performed the heterologous expression, purification and characterization of the R subunit from Y. lipolytica yeast cells, and explo...

Descripción completa

Guardado en:
Detalles Bibliográficos
Otros Autores: Kronberg, María Florencia, Giacometti, Romina, Ruiz Herrera, José, Passeron, Susana
Formato: Artículo
Lenguaje:Inglés
Materias:
PKA
Acceso en línea:http://ri.agro.uba.ar/files/intranet/articulo/2011Kronberg.pdf
LINK AL EDITOR
Aporte de:Registro referencial: Solicitar el recurso aquí
Descripción
Sumario:cAMP-dependent protein kinase [PKA] catalytic [C] and regulatory [R] subunits from Yarrowia lipolytica are encoded by single genes, TPK1 and RKA1, respectively. Here we performed the heterologous expression, purification and characterization of the R subunit from Y. lipolytica yeast cells, and explored the main biochemical features of the PKA. The purified recombinant R, active and capable to interact with C subunit was used to prepare highly specific polyclonal antiserum. Sucrose-gradient centrifugation and gel filtration analysis of both recombinant and native R revealed the monomeric nature of this subunit. Hydrodynamic parameters of the holoenzyme indicated that Y. lipolytica PKA is a dimer of 90 kDa composed of an R subunit of 42 kDa and a C subunit of 39 kDa. The identification of the N-terminal sequence was carried out by mass spectrometry analysis of the purified native R subunit. The differences between N-terminal sequences of R subunits from Y. lipolytica and other organisms, particularly a short linker that spans the inhibitory site, were discussed as the possible cause of the lack of dimerization. R was identified as a type II subunit since our results indicated that it was phosphorylated in vivo by C at S124 identified by anti-phospho-PKA substrate [RRXS/T] antibody.
ISSN:0003-9861