2bp3
CRYSTAL STRUCTURE OF FILAMIN A DOMAIN 17 AND GPIB ALPHA CYTOPLASMIC DOMAIN COMPLEX
OverviewOverview
Filamin A (FLNa), a dimeric actin cross-linking and scaffold protein with numerous intracellular binding partners, anchors the platelet adhesion glycoprotein (GP) Ib-IX-V receptor to actin cytoskeleton. We mapped the GPIbalpha binding site to a single domain of FLNa and resolved the structure of this domain and its interaction complex with the corresponding GPIbalpha cytoplasmic domain. This is the first atomic structure of this class of membrane glycoprotein-cytoskeleton connection. GPIbalpha binds in a groove formed between the C and D beta strands of FLNa domain 17. The interaction is strikingly similar to that between the beta7 integrin tail and a different FLNa domain, potentially defining a conserved motif for FLNa binding. Nevertheless, the structures also reveal specificity of the interfaces, which explains different regulatory mechanisms. To verify the topology of GPIb-FLNa interaction we also purified the native complex from platelets and showed that GPIb interacts with the C-terminus of FLNa, which is in accordance with our biochemical and structural data.
About this StructureAbout this Structure
2BP3 is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
ReferenceReference
The structure of the GPIb-filamin A complex., Nakamura F, Pudas R, Heikkinen O, Permi P, Kilpelainen I, Munday AD, Hartwig JH, Stossel TP, Ylanne J, Blood. 2006 Mar 1;107(5):1925-32. Epub 2005 Nov 17. PMID:16293600 Page seeded by OCA on Sat May 3 20:36:00 2008