PMID-sentid	Pub_year	Sent_text		comp_official_name	comp_offsetprotein_name	organism	prot_offset
15709769-4	2005	Herein we have examined in detail the catalyzed GDP/GTP exchange reaction mechanism by a Ras specific GEF, GRF1.	Guanosine Triphosphate	52-55	Rho/Rac guanine nucleotide exchange factor 2	Homo sapiens	102-105	
15709769-6	2005	The release of the Ras-bound GDP was dependent upon the concentration and the structure of the incoming nucleotide, in particular, the hydrophobicity of the beta and gamma phosphate groups, suggesting that the GTP binding step is a prerequisite for GDP dissociation, is the rate-limiting step in the GEF reaction, or both.	Guanosine Triphosphate	210-213	Rho/Rac guanine nucleotide exchange factor 2	Homo sapiens	300-303	
15709769-9	2005	These results strongly support a GEF reaction mechanism by which nucleotide exchange occurs on Ras through a direct GTP/GDP displacement model.	Guanosine Triphosphate	116-119	Rho/Rac guanine nucleotide exchange factor 2	Homo sapiens	33-36