von Lintig et al., Oncogene 2000
(Second Messenger Systems) :
Thus, cAMP activation of Rap 1 in HL-60 cells is likely through a cAMP regulated guanine nucleotide exchange factor ( cAMP-GEF ) and since cAMP does not activate Rap 1 in the variant cells, the data suggest that full post-translational processing of Rap 1 is necessary for cAMP-GEF activation of Rap 1 Guo et al., J Biol Chem 2001
:
Similar to other small GTP binding proteins, activation of Rap1 requires a guanine nucleotide exchange factor (GEF) to promote its conversion from the GDP- to GTP bound form
Birukova et al., Mol Biol Cell 2013
:
Thrombin induced EC permeability driven by rapid activation of the Rho GTPase pathway was followed by Src kinase dependent phosphorylation of the Rap1-specific guanine nucleotide exchange factor (GEF) C3G, activation of Rap1 , and initiation of EC barrier recovery