TY - JOUR
T1 - A Novel Family of Phosphatidylinositol 4-Kinases Conserved from Yeast to Humans
AU - Barylko, Barbara
AU - Gerber, Stefan H.
AU - Binns, Derk D.
AU - Grichine, Nikolai
AU - Khvotchev, Mikhail
AU - Südhof, Thomas C.
AU - Albanesi, Joseph P.
PY - 2001/3/16
Y1 - 2001/3/16
N2 - Phosphatidylinositolpolyphosphates (PIPS) are centrally involved in many biological processes, ranging from cell growth and organization of the actin cytoskeleton to endo- and exocytosis. Phosphorylation of phosphatidylinositol at the D-4 position, an essential step in the biosynthesis of PIPs, appears to be catalyzed by two biochemically distinct enzymes. However, only one of these two enzymes has been molecularly characterized. We now describe a novel class of phosphatidylinositol 4-kinases that probably corresponds to the missing element in phosphatidylinositol metabolism. These kinases are highly conserved evolutionarily, but unrelated to previously characterized phosphatidylinositol kinases, and thus represent the founding members of a new family. The novel phosphatidylinositol 4-kinases, which are widely expressed in cells, only phosphorylate phosphatidylinositol, are potently inhibited by adenosine, but are insensitive to wortmannin or phenylarsine oxide. Although they lack an obvious transmembrane domain, they are strongly attached to membranes by palmitoylation. Our data suggest that independent pathways for phosphatidylinositol 4-phosphate synthesis emerged during evolution, possibly to allow tight temporal and spatial control over the production of this key signaling molecule.
AB - Phosphatidylinositolpolyphosphates (PIPS) are centrally involved in many biological processes, ranging from cell growth and organization of the actin cytoskeleton to endo- and exocytosis. Phosphorylation of phosphatidylinositol at the D-4 position, an essential step in the biosynthesis of PIPs, appears to be catalyzed by two biochemically distinct enzymes. However, only one of these two enzymes has been molecularly characterized. We now describe a novel class of phosphatidylinositol 4-kinases that probably corresponds to the missing element in phosphatidylinositol metabolism. These kinases are highly conserved evolutionarily, but unrelated to previously characterized phosphatidylinositol kinases, and thus represent the founding members of a new family. The novel phosphatidylinositol 4-kinases, which are widely expressed in cells, only phosphorylate phosphatidylinositol, are potently inhibited by adenosine, but are insensitive to wortmannin or phenylarsine oxide. Although they lack an obvious transmembrane domain, they are strongly attached to membranes by palmitoylation. Our data suggest that independent pathways for phosphatidylinositol 4-phosphate synthesis emerged during evolution, possibly to allow tight temporal and spatial control over the production of this key signaling molecule.
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U2 - 10.1074/jbc.C000861200
DO - 10.1074/jbc.C000861200
M3 - Article
C2 - 11244087
AN - SCOPUS:0035896584
SN - 0021-9258
VL - 276
SP - 7705
EP - 7708
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 11
ER -