EMD-1510
Structure of full-length Epac2 in complex with cyclic-AMP and Rap.
EMD-1510
Single-particle23.0 Å
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Map released: 31/03/2009
Last modified: 16/04/2014
Sample Organism:
Homo sapiens,
Mus musculus,
synthetic construct
Sample: Epac2-cAMP-Rap1B complex
Deposition Authors: Arias-Palomo E
,
Rehmann H,
Hadders M,
Schwede F,
Bos JL,
Llorca O
Sample: Epac2-cAMP-Rap1B complex
Deposition Authors: Arias-Palomo E
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Structure of Epac2 in complex with a cyclic AMP analogue and RAP1B.
Rehmann H,
Arias-Palomo E
,
Hadders MA,
Schwede F,
Llorca O
,
Bos JL
(2008) Nature , 455 , 124 - 127
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(2008) Nature , 455 , 124 - 127
Abstract:
Epac proteins are activated by binding of the second messenger cAMP and then act as guanine nucleotide exchange factors for Rap proteins. The Epac proteins are involved in the regulation of cell adhesion and insulin secretion. Here we have determined the structure of Epac2 in complex with a cAMP analogue (Sp-cAMPS) and RAP1B by X-ray crystallography and single particle electron microscopy. The structure represents the cAMP activated state of the Epac2 protein with the RAP1B protein trapped in the course of the exchange reaction. Comparison with the inactive conformation reveals that cAMP binding causes conformational changes that allow the cyclic nucleotide binding domain to swing from a position blocking the Rap binding site towards a docking site at the Ras exchange motif domain.
Epac proteins are activated by binding of the second messenger cAMP and then act as guanine nucleotide exchange factors for Rap proteins. The Epac proteins are involved in the regulation of cell adhesion and insulin secretion. Here we have determined the structure of Epac2 in complex with a cAMP analogue (Sp-cAMPS) and RAP1B by X-ray crystallography and single particle electron microscopy. The structure represents the cAMP activated state of the Epac2 protein with the RAP1B protein trapped in the course of the exchange reaction. Comparison with the inactive conformation reveals that cAMP binding causes conformational changes that allow the cyclic nucleotide binding domain to swing from a position blocking the Rap binding site towards a docking site at the Ras exchange motif domain.