TY - JOUR
T1 - The Pleckstrin Homology Domain of Phospholipase C-δ1 Binds with High Affinity to Phosphatidylinositol 4,5-Bisphosphate in Bilayer Membranes
AU - Garcia, Pilar
AU - Gupta, Rakesh
AU - Shah, Shefali
AU - Morris, Andrew J.
AU - Rudge, Simon A.
AU - Scarlata, Suzanne
AU - Petrova, Victoria
AU - McLaughlin, Stuart
AU - Rebecchi, Mario J.
PY - 1995/12
Y1 - 1995/12
N2 - The pleckstrin homology (PH) domain of phospholipase C-δ1 (PLC-δ1) binds to phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) in phospholipid membranes with an affinity (Ka ~ 106 M-1) and specificity comparable to those of the native enzyme. PLC-δ1 and its PH domain also bind inositol 1,4,5-trisphosphate, the polar head group of PI(4,5)P2, with comparable affinity and approximately 1:1 stoichiometry. A peptide corresponding to amino acids 30-43 of the PLC-δ1 PH domain contains several basic residues predicted to bind PI(4,5)P2, but binds weakly and with little specificity for PI(4,5)P2; hence the tertiary structure of the isolated PH domain is required for high affinity PI(4,5)P2 binding. Our PI-(4,5)P2 binding results support the hypothesis that the intact PH domain, serving as a specific tether, directs PLC-δ1 to membranes enriched in PI(4,5)P2 and permits the active site, located elsewhere in the protein, to hydrolyze multiple substrate molecules before this enzyme dissociates from the membrane surface.
AB - The pleckstrin homology (PH) domain of phospholipase C-δ1 (PLC-δ1) binds to phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) in phospholipid membranes with an affinity (Ka ~ 106 M-1) and specificity comparable to those of the native enzyme. PLC-δ1 and its PH domain also bind inositol 1,4,5-trisphosphate, the polar head group of PI(4,5)P2, with comparable affinity and approximately 1:1 stoichiometry. A peptide corresponding to amino acids 30-43 of the PLC-δ1 PH domain contains several basic residues predicted to bind PI(4,5)P2, but binds weakly and with little specificity for PI(4,5)P2; hence the tertiary structure of the isolated PH domain is required for high affinity PI(4,5)P2 binding. Our PI-(4,5)P2 binding results support the hypothesis that the intact PH domain, serving as a specific tether, directs PLC-δ1 to membranes enriched in PI(4,5)P2 and permits the active site, located elsewhere in the protein, to hydrolyze multiple substrate molecules before this enzyme dissociates from the membrane surface.
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U2 - 10.1021/bi00049a039
DO - 10.1021/bi00049a039
M3 - Article
C2 - 8519781
AN - SCOPUS:0028787055
SN - 0006-2960
VL - 34
SP - 16228
EP - 16234
JO - Biochemistry
JF - Biochemistry
IS - 49
ER -