TY - JOUR
T1 - Slp2-a inactivates ezrin by recruiting protein phosphatase 1 to the plasma membrane
AU - Yasuda, Takao
AU - Homma, Yuta
AU - Fukuda, Mitsunori
N1 - Funding Information:
This work was supported in part by the Japan Society for the Promotion of Science KAKENHI (grant number 242766 to T.Y.); by grants-in-aid for Scientific Research from the Ministry of Education, Culture, Sports, and Technology (MEXT) of Japan (grant number 26670149 to T.Y.; and grant numbers 24657125 and 26111501 to M.F.); and by a grant from the Naito Foundation (to M.F.). We thank Megumi Aizawa for technical assistance and members of the Fukuda Laboratory for valuable discussions.
Publisher Copyright:
© 2015 Elsevier Inc. All rights reserved.
PY - 2015/5/12
Y1 - 2015/5/12
N2 - Synaptotagmin-like protein 2-a (Slp2-a) was originally described as a membrane trafficking protein that consists of a Slp homology domain (SHD), a linker domain, and tandem C2 domains (named the C2A domain and C2B domain). Slp2-a mediates docking of Rab27-bearing vesicles to the plasma membrane through simultaneous interaction with Rab27 and phospholipids in the plasma membrane. We have recently reported that Slp2-a regulates renal epithelial cell size through interaction with Rap1GAP2 via the C2B domain independently of Rab27 and demonstrated the presence of excess activation of ezrin, a membrane-cytoskeleton linker and signal transducer, in Slp2-a-knockdown Madin-Darby canine kidney II (MDCK II) cells. However, the precise mechanism of ezrin inactivation by Slp2-a in cell size control has remained largely unknown. In this study, we investigated the functional relationship between Slp2-a and ezrin in MDCK II cells. The results showed that activation of ezrin in control MDCK II cells either pharmacologically or by overexpression of a constitutively active ezrin mutant caused an increase in cell size, whereas inactivation of ezrin in Slp2-a-knockdown cells by a specific ezrin inhibitor restored them to their normal cell size. We also found that Slp2-a interacts via its previously uncharacterized linker domain with protein phosphatase 1β (PP1β), which inactivates ezrin, and that the interaction is required for the plasma membrane localization of PP1β. These results indicate that Slp2-a inactivates ezrin by recruiting PP1 to the plasma membrane.
AB - Synaptotagmin-like protein 2-a (Slp2-a) was originally described as a membrane trafficking protein that consists of a Slp homology domain (SHD), a linker domain, and tandem C2 domains (named the C2A domain and C2B domain). Slp2-a mediates docking of Rab27-bearing vesicles to the plasma membrane through simultaneous interaction with Rab27 and phospholipids in the plasma membrane. We have recently reported that Slp2-a regulates renal epithelial cell size through interaction with Rap1GAP2 via the C2B domain independently of Rab27 and demonstrated the presence of excess activation of ezrin, a membrane-cytoskeleton linker and signal transducer, in Slp2-a-knockdown Madin-Darby canine kidney II (MDCK II) cells. However, the precise mechanism of ezrin inactivation by Slp2-a in cell size control has remained largely unknown. In this study, we investigated the functional relationship between Slp2-a and ezrin in MDCK II cells. The results showed that activation of ezrin in control MDCK II cells either pharmacologically or by overexpression of a constitutively active ezrin mutant caused an increase in cell size, whereas inactivation of ezrin in Slp2-a-knockdown cells by a specific ezrin inhibitor restored them to their normal cell size. We also found that Slp2-a interacts via its previously uncharacterized linker domain with protein phosphatase 1β (PP1β), which inactivates ezrin, and that the interaction is required for the plasma membrane localization of PP1β. These results indicate that Slp2-a inactivates ezrin by recruiting PP1 to the plasma membrane.
KW - Cell size
KW - Ezrin
KW - MDCK II
KW - Protein phosphatase 1
KW - Slp2-a
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U2 - 10.1016/j.bbrc.2015.03.099
DO - 10.1016/j.bbrc.2015.03.099
M3 - Article
C2 - 25817786
AN - SCOPUS:84937764940
VL - 460
SP - 896
EP - 902
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
SN - 0006-291X
IS - 4
ER -