INVESTIGADORES
LEIVA Natalia Lorena
congresos y reuniones científicas
Título:
DIFFERENT PKC ISOFORMS PHOSPHORYLATE THE SMALL GTPASE RAB11
Autor/es:
PAVAROTTI M; LEIVA N; CAPMANY A; COLOMBO MI; DAMIANI MT
Lugar:
Mar del Plata, Buenos Aires, Argentina
Reunión:
Congreso; XLIII Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular.; 2007
Institución organizadora:
Sociedad Argentina de Investigaciones en Bioquímica y Biología Molecular.
Resumen:
The Rab family of monomeric GTPases regulates intracellular
traffic. Some Rabs can be phosphorylated by specific kinases. This
post-transductional modification changes Rab`s affinity for
effectors as well as its function. Rab11 is localized to the endosomal
recycling compartment and we have previously demonstrated that
Rab11 regulates phagocytosis and recycling from phagosomes. It
has been shown that upon sustained stimulation with phorbol esters,
PKC and II translocate towards Rab11-enriched vesicles. Taken
together, these observations prompted us to investigate the
possibility that Rab11 might serve as a substrate for PKC.We used
on line predictive software to analyze Rab11`s putative
phosphorylation sites and we found different consensus sites for
basophilic serine/threonine kinases, like PKC. Then, we performed
phosphorylation assays by use of [ P]ATP, GST-Rab11
and cytosol. The samples were resolved by SDS-PAGE and protein
phosphorylation detected by autoradiography. Our results show
that Rab11 is phosphorylated by kinases present in cytosol. To
further analyze the role of PKC on Rab11 phosphorylation, we used
different pure PKC isoforms. These experiments demonstrated that
Rab11 is phosphorylated by the classic PKC , PKC II and the
novel PKC . The phosphorylation of Rab11 is likely to be a
regulatory event that affects the interaction with its effectors.