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P. PENELA Y COLS. AN. R. ACAD. NAC. FARM

based on the dynamic regulation of the interaction of GRK2 with GIT1
(Penela et al., EMBO J., in press). These results suggest that the overall
contribution of GRK2 to cell migration would be cell-type specific and
stimulus-specific. This possibility is currently being investigated in our
group.

In sum, the complex GRK2 "interactome" with multiple signaling
proteins involved in inflammation and cell migration (summarized in
Figure 1), its reported alterations in inflammatory disorders and the
network of mechanisms controlling its activity and expression levels
suggest key functional roles for GRK2 in inflammation, that deserve to be
explored in the future.

ACKNOWLEDGEMENTS

Our laboratory is funded by grants from Ministerio de Educación y
Ciencia (SAF2005-03053), Fundación Ramón Areces, Fundación Mutua
Madrileña, The Cardiovascular Network (RECAVA) of Ministerio Sanidad
y Consumo-Instituto Carlos III (RD06-0014/0037 and PI060713),
Comunidad de Madrid (S-SAL-0159-2006), and the MAIN European
Network (LSHG-CT-2003-502935).

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