Fc Receptors Oct. 28, 2009 Extra reading on web. Daniel Conrad 423 MSB, 828-2311 I. CD23. CD23 – Member of the C-type animal lectin family. Trimeric structure means Avidity is important in Binding. CD23 Summary. Only Fc receptor that with no relationship to Ig superfamily
423 MSB, 828-2311
Avidity is important in
Shows interaction of a-chain
Cyrstal structure of complex has revealed site of interaction.
Fc interaction.eRI is part of a family of Multichain immune recognition
Receptors (MIRRs) that use an ITAM activation scenario
ITAM Motif interaction.
Receptor activates PTK either directly or indirectly – recruits syk family – activates
PI3K which phos. PI3,4,5P3 – this recruits PLCg and Tec family – which produces
IP3 – this releases intracellular Ca and opens CRAC (Ca release activated channels)
(Cell 94:5-8, 1998 – reference for above figure if needed)
PH is Pleckstrin Homology domain – binds PI 3,4,5 P3 recruits syk family – activates
Summary of FcR structure showing ITAMs or ITIMs in cytoplasm recruits syk family – activates
Cartoon showing glycerol-phosphotidyl inositol (GPI) recruits syk family – activates
PLD and PLC are enzymes that cleave at positions
KAR is NK activating receptor recruits syk family – activates
Examples of proteins that recruits syk family – activates
have an ITIM in cytoplasm
“ITIMs control ITAMs” recruits syk family – activates
IP3 cannot be made – blocking calcium release.
IgA Transport – then