TY - JOUR
T1 - The PX domain as a novel phosphoinositide-binding module
AU - Ago, Tetsuro
AU - Takeya, Ryu
AU - Hiroaki, Hidekazu
AU - Kuribayashi, Futoshi
AU - Ito, Takashi
AU - Kohda, Daisuke
AU - Sumimoto, Hideki
N1 - Funding Information:
We are grateful to Professor Masato Hirata (Kyushu University) for helpful discussion and technical advise. We also thank Yohko Kage (Kyushu University) for excellent technical assistance. This work was partly supported by grants from Ministry of Education, Culture, Sports, Science and Technology, Japan.
PY - 2001/9/28
Y1 - 2001/9/28
N2 - The phox (phagocyte oxidase) homology (PX) domain occurs in the mammalian phox proteins p40phox and p47phox, the polarity establishment protein Bem1p in budding yeast, and a variety of proteins involved in membrane trafficking. Here we show that the PX domains of p40phox and p47phox directly bind to phosphoinositides: p40phox prefers Ptdlns(3)P, while p47phox does Ptdlns(4)P and Ptdlns(3,4)P2. In addition, the Bem1p PX domain also interacts with Ptdlns(4)P. When the p40phox PX domain is expressed as a fusion to green fluorescent protein in HeLa cells, it exists at early endosomes where Ptdlns(3)P is enriched. Furthermore, a mutant p40phox PX carrying the substitution of Lys for Arg105 only weakly binds to phosphoinositides in vitro, and fails to locate to early endosomes. Thus the PX domain functions as a novel phosphoinositide-binding module and likely participates in targeting of proteins to membranes.
AB - The phox (phagocyte oxidase) homology (PX) domain occurs in the mammalian phox proteins p40phox and p47phox, the polarity establishment protein Bem1p in budding yeast, and a variety of proteins involved in membrane trafficking. Here we show that the PX domains of p40phox and p47phox directly bind to phosphoinositides: p40phox prefers Ptdlns(3)P, while p47phox does Ptdlns(4)P and Ptdlns(3,4)P2. In addition, the Bem1p PX domain also interacts with Ptdlns(4)P. When the p40phox PX domain is expressed as a fusion to green fluorescent protein in HeLa cells, it exists at early endosomes where Ptdlns(3)P is enriched. Furthermore, a mutant p40phox PX carrying the substitution of Lys for Arg105 only weakly binds to phosphoinositides in vitro, and fails to locate to early endosomes. Thus the PX domain functions as a novel phosphoinositide-binding module and likely participates in targeting of proteins to membranes.
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U2 - 10.1006/bbrc.2001.5629
DO - 10.1006/bbrc.2001.5629
M3 - Article
C2 - 11563857
AN - SCOPUS:0035964873
SN - 0006-291X
VL - 287
SP - 733
EP - 738
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 3
ER -