Spinophilin is required for maintaining the sustained ERK1/2 activation induced by the Del301-303 α_2BAR in MEFs.

Abstract

<p>(A) Sp^+/+ MEFs expressing the WT or Del301-303 α_2BAR were stimulated with 1μM clonidine for indicated time points. Representative blots show phospho- and total-ERK1/2. (B) Quantitation of ERK1/2 activation in Sp^+/+ MEFs. The relative ERK1/2 activation at each time point was expressed as a ratio to the peak level of ERK1/2 activation in the same experiment, which was arbitrarily defined as 1.0. n = 7 for the WT α_2B group and n = 6 for the Del301-303 α_2B group. *, <i>p</i><0.05; ***, <i>p</i><0.001, WT α_2B<i>vs</i>. Del301-303 α_2B. (C) Sp^-/- MEFs expressing the WT or Del301-303 α_2BAR were stimulated with 1μM clonidine for indicated time points. Representative blots show phospho- and total-ERK1/2. (D) Quantitation of ERK1/2 activation in Sp^-/- MEFs. n = 4 for the WT α_2B group and n = 3 for the Del301-303 α_2B group.</p