TY - JOUR
T1 - Identification of the binding site for acidic phospholipids on the PH domain of dynamin
T2 - Implications for stimulation of GTPase activity
AU - Zheng, Jie
AU - Cahill, Sean M.
AU - Lemmon, Mark A.
AU - Fushman, David
AU - Schlessinger, Joseph
AU - Cowburn, David
N1 - Funding Information:
We are grateful to Dr M. Saraste and Professor C. Collins for communication of results before publication and to Dr Kathryn Ferguson for valuable discussions. Professor J. Kuriyan and Dr C.-H. Lee generously provided access to light-scattering equipment. This work was supported in part by American Cancer Society grant NP-922 to D.C., and at NYU by a grant from Sugen (to J.S.). M.A.L. is the Marion Abbe Fellow of the Damon Runyon-Walter Winchell Cancer Research Fund (DRG-1243).
PY - 1996/1/12
Y1 - 1996/1/12
N2 - It has recently been suggested that pleckstrin homology (PH) domains bind specifically to phospholipids, with phosphatidylinositol-4,5-bisphosphate (PtdIns(4,5)P2) being most strongly bound. This observation suggests that PH domains may be responsible for membrane association of proteins in which they occur. Further, this membrane association may be regulated by enzymes that modify lipid head groups to which PH domains may bind. We have studied the binding of phospholipids to the PH domain of human dynamin, a 100 kDa GTPase that is involved in the initial stages of endocytosis. We describe a rapid method for screening PH domain/ligand interactions that gives precise binding constants. We confirm that PtdIns(4,5)P2 can bind to dynamin PH domain, although not in an aggregated state. Using NMR spectroscopy, we have mapped a specific site on the surface of dynamin PH domain of which binding of gIns(1,4,5)P3 (the head-group skeleton of PtdIns(4,5)P2) occurs. The relative affinity of acidic phospholipids for dynamin PH domain correlates with their ability to activate the GTPase of dynamin. We propose, therefore, that the interaction of these phospholipids with dynamin is likely to occur via the PH domain. Given the fact that PH domains are often found in proteins associated with GTPase activity, or in guanine nucleotide exchange factors, we suggest that one role of PH domains may be to couple phosphatidylinositol signalling to GTP hydrolysis.
AB - It has recently been suggested that pleckstrin homology (PH) domains bind specifically to phospholipids, with phosphatidylinositol-4,5-bisphosphate (PtdIns(4,5)P2) being most strongly bound. This observation suggests that PH domains may be responsible for membrane association of proteins in which they occur. Further, this membrane association may be regulated by enzymes that modify lipid head groups to which PH domains may bind. We have studied the binding of phospholipids to the PH domain of human dynamin, a 100 kDa GTPase that is involved in the initial stages of endocytosis. We describe a rapid method for screening PH domain/ligand interactions that gives precise binding constants. We confirm that PtdIns(4,5)P2 can bind to dynamin PH domain, although not in an aggregated state. Using NMR spectroscopy, we have mapped a specific site on the surface of dynamin PH domain of which binding of gIns(1,4,5)P3 (the head-group skeleton of PtdIns(4,5)P2) occurs. The relative affinity of acidic phospholipids for dynamin PH domain correlates with their ability to activate the GTPase of dynamin. We propose, therefore, that the interaction of these phospholipids with dynamin is likely to occur via the PH domain. Given the fact that PH domains are often found in proteins associated with GTPase activity, or in guanine nucleotide exchange factors, we suggest that one role of PH domains may be to couple phosphatidylinositol signalling to GTP hydrolysis.
KW - Fluorescence
KW - Ligand binding
KW - NMR
KW - PH domain
KW - Phospholipid
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U2 - 10.1006/jmbi.1996.0002
DO - 10.1006/jmbi.1996.0002
M3 - Editorial
C2 - 8568861
AN - SCOPUS:0029978885
SN - 0022-2836
VL - 255
SP - 14
EP - 21
JO - Journal of Molecular Biology
JF - Journal of Molecular Biology
IS - 1
ER -