Munc-18-1 inhibits phospholipase D activity by direct interaction in an epidermal growth factor-reversible manner
SCIE
SCOPUS
- Title
- Munc-18-1 inhibits phospholipase D activity by direct interaction in an epidermal growth factor-reversible manner
- Authors
- Lee, HY; Park, JB; Jang, IH; Chae, YC; Kim, JH; Kim, IS; Suh, PG; Ryu, SH
- Date Issued
- 2004-01
- Publisher
- AMER SOC BIOCHEMISTRY MOLECULAR BIOLO
- Abstract
- Mammalian phospholipase D (PLD) has been reported to be a key enzyme for epidermal growth factor (EGF)induced cellular signaling, however, the regulatory mechanism of PLD is still unclear. In this report, we found that Munc-18-1 is a potent negative regulator of PLD in the basal state and that its inhibition is abolished by EGF stimulation. We investigated PLD-binding proteins obtained from rat brain extract, and identified a 67-kDa protein as Munc-18-1 by peptide-mass fingerprinting. The direct association between PLD and Munc-18-1 was confirmed by in vitro binding analysis using the purified proteins, and their binding sites were identified as the phox homology domain of PLD and multiple sites of Munc-18-1. PLD activity was potently inhibited by Munc-18-1 in vitro (IC50 = 2 - 5 nM), and the cotransfection of COS-7 cells with Munc-18-1 and PLD inhibited basal PLD activity in vivo. In the basal state, Munc-18-1 coprecipitated with PLD and colocalized with PLD2 at the plasma membrane of COS-7 cells. EGF treatment triggered the dissociation of Munc-18-1 from PLD when PLD was activated by EGF. The dissociation of the endogenous interaction between Munc-18-1 and PLD, and the activation of PLD by EGF were also observed in primary cultured chromaffin cells. These results suggest that Munc-18-1 is a potent negative regulator of basal PLD activity and that EGF stimulation abolishes this interaction.
- URI
- https://oasis.postech.ac.kr/handle/2014.oak/17983
- DOI
- 10.1074/JBC.M310976200
- ISSN
- 0021-9258
- Article Type
- Article
- Citation
- JOURNAL OF BIOLOGICAL CHEMISTRY, vol. 279, no. 16, page. 16339 - 16348, 2004-01
- Files in This Item:
- There are no files associated with this item.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.