Structure of the PIN/LC8 dimer with a bound peptide.

Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853-1301, USA.
Nature Structural Biology 09/1999; 6(8):735-40. DOI: 10.1038/11501
Source: PubMed

ABSTRACT The structure of the protein known both as neuronal nitric oxide synthase inhibitory protein, PIN (protein inhibitor of nNOS), and also as the 8 kDa dynein light chain (LC8) has been solved by X-ray diffraction. Two PIN/LC8 monomers related by a two-fold axis form a rectangular dimer. Two pairs of alpha-helices cover opposite faces, and each pair of helices packs against a beta-sheet with five antiparallel beta-strands. Each five-stranded beta-sheet contains four strands from one monomer and a fifth strand from the other monomer. A 13-residue peptide from nNOS is bound to the dimer in a deep hydrophobic groove as a sixth antiparallel beta-strand. The structure provides key insights into dimerization of and peptide binding by the multifunctional PIN/LC8 protein.

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