2R2I

Myristoylated Guanylate Cyclase Activating Protein-1 with Calcium Bound

Summary for 2R2I

• Entry DOI: 10.2210/pdb2r2i/pdb
• Descriptor: Guanylyl cyclase-activating protein 1, CALCIUM ION, MYRISTIC ACID, ... (5 entities in total)
• Functional Keywords: ef hand, gcap, guanylate cyclase activating protein, gcap1, gcap-1, calcium, lipoprotein, myristate, sensory transduction, vision, lyase activator
• Biological source: Gallus gallus (chicken)
• Total number of polymer chains: 1
• Total formula weight: 23391.84

Authors

Stephen, R. (deposition date: 2007-08-25, release date: 2007-12-11, Last modification date: 2021-10-20)

Primary citation

Stephen, R.,Bereta, G.,Golczak, M.,Palczewski, K.,Sousa, M.C.
Stabilizing function for myristoyl group revealed by the crystal structure of a neuronal calcium sensor, guanylate cyclase-activating protein 1.
Structure, 15:1392-1402, 2007

PubMed Abstract: Guanylate cyclase-activating proteins (GCAPs) are Ca(2+)-binding proteins myristoylated at the N terminus that regulate guanylate cyclases in photoreceptor cells and belong to the family of neuronal calcium sensors (NCS). Many NCS proteins display a recoverin-like "calcium-myristoyl switch" whereby the myristoyl group, buried inside the protein in the Ca(2+)-free state, becomes fully exposed upon Ca(2+) binding. Here we present a 2.0 A resolution crystal structure of myristoylated GCAP1 with Ca(2+) bound. The acyl group is buried inside Ca(2+)-bound GCAP1. This is in sharp contrast to Ca(2+)-bound recoverin, where the myristoyl group is solvent exposed. Furthermore, we provide direct evidence that the acyl group in GCAP1 remains buried in the Ca(2+)-free state and does not undergo switching. A pronounced kink in the C-terminal helix and the presence of the myristoyl group allow clustering of sequence elements crucial for GCAP1 activity.

PubMed: 17997965
DOI: 10.1016/j.str.2007.09.013

Experimental method

X-RAY DIFFRACTION (2 Å)