TY - JOUR
T1 - The carboxy-terminal tail domain of vinculin contains a cryptic binding site for acidic phospholipids
AU - Johnson, Robert P.
AU - Craig, Susan W.
PY - 1995/5/5
Y1 - 1995/5/5
N2 - Using a gel filtration assay, we have characterized the binding of acidic phospholipids to vinculin. Vinculin binds phosphatidyinositol (Kd ∼ 5 μM) in a reversible, saturable manner in low ionic strength buffers. This interaction is inhibited substantially at 100 mM NaCl and therefore may not be of physiological interest. In contrast, the carboxy-terminal 30-kDa fragment of vinculin, produced by S. aureus V8 protease cleavage, binds acidic phospholipids more tightly than the intact protein, and in a manner insensitive to 100 mM NaCl. Re-addition of the 95-kDa head fragment to the tail restores salt-sensitivity to the tail-lipid interaction. These data indicate that under physiologic ionic conditions, the intramolecular head-tail interaction in vinculin masks a high affinity acidic phospholipid binding site present in the tail domain.
AB - Using a gel filtration assay, we have characterized the binding of acidic phospholipids to vinculin. Vinculin binds phosphatidyinositol (Kd ∼ 5 μM) in a reversible, saturable manner in low ionic strength buffers. This interaction is inhibited substantially at 100 mM NaCl and therefore may not be of physiological interest. In contrast, the carboxy-terminal 30-kDa fragment of vinculin, produced by S. aureus V8 protease cleavage, binds acidic phospholipids more tightly than the intact protein, and in a manner insensitive to 100 mM NaCl. Re-addition of the 95-kDa head fragment to the tail restores salt-sensitivity to the tail-lipid interaction. These data indicate that under physiologic ionic conditions, the intramolecular head-tail interaction in vinculin masks a high affinity acidic phospholipid binding site present in the tail domain.
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U2 - 10.1006/bbrc.1995.1641
DO - 10.1006/bbrc.1995.1641
M3 - Article
C2 - 7741737
AN - SCOPUS:0029009673
SN - 0006-291X
VL - 210
SP - 159
EP - 164
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 1
ER -