TY - JOUR
T1 - The platelet receptor CLEC-2 is active as a dimer
AU - Watson, Aleksandra A.
AU - Christou, Charita M.
AU - James, John R.
AU - Fenton-May, Angharad E.
AU - Moncayo, Gerald E.
AU - Mistry, Anita R.
AU - Davis, Simon J.
AU - Gilbert, Robert J C
AU - Chakera, Aron
AU - O'Callaghan, Chris A.
PY - 2009/11/24
Y1 - 2009/11/24
N2 - The platelet receptor CLEC-2 binds to the snake venom toxin rhodocytin and the tumor cell surface protein podoplanin. Binding of either of these ligands promotes phosphorylation of a single tyrosine residue in the YXXL motif in the intracellular domain of CLEC-2. Phosphorylation of this tyrosine initiates binding of spleen tyrosine kinase (Syk) and triggers further downstream signaling events and ultimately potent platelet activation and aggregation. However, it is unclear how a single YXXL motif can interact efficiently with Syk, which usually recognizes two tandem YXXL repeats presented as an immunoreceptor tyrosine-based activation motif (ITAM). Using bioluminescence resonance energy transfer, coimmuno-preciptitation, recombinant protein expression and analytical gel filtration chromatography, surface plasmon resonance, Western blotting, multiangle light scattering (MALS), and analytical ultracentrifugation, we show that CLEC-2 exists as a non-disulfide-linked homodimer which could alloweach Syk molecule to interact with two YXXL motifs, one from each CLEC-2 monomer.
AB - The platelet receptor CLEC-2 binds to the snake venom toxin rhodocytin and the tumor cell surface protein podoplanin. Binding of either of these ligands promotes phosphorylation of a single tyrosine residue in the YXXL motif in the intracellular domain of CLEC-2. Phosphorylation of this tyrosine initiates binding of spleen tyrosine kinase (Syk) and triggers further downstream signaling events and ultimately potent platelet activation and aggregation. However, it is unclear how a single YXXL motif can interact efficiently with Syk, which usually recognizes two tandem YXXL repeats presented as an immunoreceptor tyrosine-based activation motif (ITAM). Using bioluminescence resonance energy transfer, coimmuno-preciptitation, recombinant protein expression and analytical gel filtration chromatography, surface plasmon resonance, Western blotting, multiangle light scattering (MALS), and analytical ultracentrifugation, we show that CLEC-2 exists as a non-disulfide-linked homodimer which could alloweach Syk molecule to interact with two YXXL motifs, one from each CLEC-2 monomer.
UR - http://www.scopus.com/inward/record.url?scp=72749115196&partnerID=8YFLogxK
U2 - 10.1021/bi901427d
DO - 10.1021/bi901427d
M3 - Article
C2 - 19824697
AN - SCOPUS:72749115196
SN - 0006-2960
VL - 48
SP - 10988
EP - 10996
JO - Biochemistry
JF - Biochemistry
IS - 46
ER -