RRC ID 37034
著者 Takagishi T, Oda M, Kabura M, Kurosawa M, Tominaga K, Urano S, Ueda Y, Kobayashi K, Kobayashi T, Sakurai J, Terao Y, Nagahama M.
タイトル Clostridium perfringens Alpha-Toxin Induces Gm1a Clustering and Trka Phosphorylation in the Host Cell Membrane.
ジャーナル PLoS One
Abstract Clostridium perfringens alpha-toxin elicits various immune responses such as the release of cytokines, chemokines, and superoxide via the GM1a/TrkA complex. Alpha-toxin possesses phospholipase C (PLC) hydrolytic activity that contributes to signal transduction in the pathogenesis of gas gangrene. Little is known about the relationship between lipid metabolism and TrkA activation by alpha-toxin. Using live-cell fluorescence microscopy, we monitored transbilayer movement of diacylglycerol (DAG) with the yellow fluorescent protein-tagged C1AB domain of protein kinase C-γ (EYFP-C1AB). DAG accumulated at the marginal region of the plasma membrane in alpha toxin-treated A549 cells, which also exhibited GM1a clustering and TrkA phosphorylation. Annexin V binding assays showed that alpha-toxin induced the exposure of phosphatidylserine on the outer leaflet of the plasma membrane. However, H148G, a variant toxin which binds cell membrane and has no enzymatic activity, did not induce DAG translocation, GM1a clustering, or TrkA phosphorylation. Alpha-toxin also specifically activated endogenous phospholipase Cγ-1 (PLCγ-1), a TrkA adaptor protein, via phosphorylation. U73122, an endogenous PLC inhibitor, and siRNA for PLCγ-1 inhibited the formation of DAG and release of IL-8. GM1a accumulation and TrkA phosphorylation in A549 cells treated with alpha-toxin were also inhibited by U73122. These results suggest that the flip-flop motion of hydrophobic lipids such as DAG leads to the accumulation of GM1a and TrkA. We conclude that the formation of DAG by alpha-toxin itself (first step) and activation of endogenous PLCγ-1 (second step) leads to alterations in membrane dynamics, followed by strong phosphorylation of TrkA.
巻・号 10(4)
ページ e0120497
公開日 2015-1-1
DOI 10.1371/journal.pone.0120497
PII PONE-D-14-51581
PMID 25910247
PMC PMC4409118
MeSH Bacterial Toxins / metabolism* Bacterial Toxins / pharmacology Biological Transport Calcium-Binding Proteins / metabolism* Calcium-Binding Proteins / pharmacology Cell Line Cell Membrane / drug effects Cell Membrane / metabolism* Diglycerides / metabolism G(M1) Ganglioside / metabolism* Host-Pathogen Interactions Humans Interleukin-8 / metabolism Models, Biological Phospholipase C gamma / genetics Phospholipase C gamma / metabolism Phosphorylation / drug effects RNA Interference Receptor, trkA / metabolism* Type C Phospholipases / metabolism* Type C Phospholipases / pharmacology
IF 2.74
引用数 12
WOS 分野 BIOCHEMISTRY & MOLECULAR BIOLOGY
リソース情報
ヒト・動物細胞 A549