Crystal structure of the cytoskeleton-associated protein glycine-rich (CAP-Gly) domain

University of Alabama at Birmingham, Birmingham, Alabama, United States
Journal of Biological Chemistry (Impact Factor: 4.6). 01/2003; 277(50):48596-601. DOI: 10.1074/jbc.M208512200
Source: PubMed

ABSTRACT Cytoskeleton-associated proteins (CAPs) are involved in the organization of microtubules and transportation of vesicles and organelles along the cytoskeletal network. A conserved motif, CAP-Gly, has been identified in a number of CAPs, including CLIP-170 and dynactins. The crystal structure of the CAP-Gly domain of Caenorhabditis elegans F53F4.3 protein, solved by single wavelength sulfur-anomalous phasing, revealed a novel protein fold containing three beta-sheets. The most conserved sequence, GKNDG, is located in two consecutive sharp turns on the surface, forming the entrance to a groove. Residues in the groove are highly conserved as measured from the information content of the aligned sequences. The C-terminal tail of another molecule in the crystal is bound in this groove.

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