| RRC ID |
66038
|
| 著者 |
Ikeda Y, Kawai K, Ikawa A, Kawamoto K, Egami Y, Araki N.
|
| タイトル |
Rac1 switching at the right time and location is essential for Fcγ receptor-mediated phagosome formation.
|
| ジャーナル |
J Cell Sci
|
| Abstract |
Lamellipodia are sheet-like cell protrusions driven by actin polymerization mainly through Rac1, a GTPase molecular switch. In Fcγ receptor-mediated phagocytosis of IgG-opsonized erythrocytes (IgG-Es), Rac1 activation is required for lamellipodial extension along the surface of IgG-Es. However, the significance of Rac1 deactivation in phagosome formation is poorly understood. Our live-cell imaging and electron microscopy revealed that RAW264 macrophages expressing a constitutively active Rac1 mutant showed defects in phagocytic cup formation, while lamellipodia were formed around IgG-Es. Because activated Rac1 reduced the phosphorylation levels of myosin light chains, failure of the cup formation is probably due to inhibition of actin/myosin II contractility. Reversible photo-manipulation of the Rac1 switch in macrophages fed with IgG-Es could phenocopy two lamellipodial motilities: outward-extension and cup-constriction by Rac1 ON and OFF, respectively. In conjunction with fluorescence resonance energy transfer imaging of Rac1 activity, we provide a novel mechanistic model of phagosome formation spatiotemporally controlled by Rac1 switching within a phagocytic cup.
|
| 巻・号 |
130(15)
|
| ページ |
2530-2540
|
| 公開日 |
2017-8-1
|
| DOI |
10.1242/jcs.201749
|
| PII |
jcs.201749
|
| PMID |
28600322
|
| MeSH |
Animals
Macrophages / immunology*
Mice
Models, Immunological*
Neuropeptides / immunology*
Phagosomes / immunology*
Phosphorylation / immunology
RAW 264.7 Cells
Receptors, IgG / immunology*
rac1 GTP-Binding Protein / immunology*
|
| IF |
4.573
|
| リソース情報 |
| ヒト・動物細胞 |
RAW 264(RCB0535) |
