Transient recruitment of M-Ras GTPase to phagocytic cups in RAW264 macrophages during FcγR-mediated phagocytosis
Transient recruitment of M-Ras GTPase to phagocytic cups in RAW264 macrophages during FcγR-mediated phagocytosis
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FcγR 介导的吞噬作用期间，M-Ras GTPase 瞬时募集至 RAW264 巨噬细胞的吞噬杯
DOI：
10.1093/jmicro/dfx131
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发表时间：
2018
期刊：
影响因子：
1.8
通讯作者：
Araki N
中科院分区：
文献类型：
--
作者：
Egami Y;Araki N
M-Ras 是 Ras 超家族的成员，已知参与多种细胞过程。然而，其参与 FcγR 介导的吞噬作用仍不清楚。我们检查了 RAW264 巨噬细胞中 IgG 调理红细胞 (IgG-Es) 吞噬过程中 M-Ras 的时空定位。通过荧光蛋白融合的M-Ras的活细胞成像，我们发现在吞噬体形成的早期阶段，M-Ras定位于吞噬杯的膜上。值得注意的是，比例图像分析表明 M-Ras 集中在形成吞噬体的膜中。此外，我们对 M-Ras 突变体表达的分析表明，在表达 GDP 锁定突变体 M-Ras-S27N 的细胞中，吞噬体形成受到显着抑制。相反，野生型 M-Ras 或 GTP 锁定突变体 M-Ras-G22V 的表达促进 IgG-E 的摄取。这些数据表明 M-Ras 是 FcγR 介导的吞噬途径的新成分，可能调节巨噬细胞中吞噬体的形成。
M-Ras, a member of the Ras superfamily, is known to be involved in diverse cellular processes. However, its involvement in FcγR-mediated phagocytosis remains unknown. We examined the spatiotemporal localization of M-Ras during the engulfment of IgG-opsonized erythrocytes (IgG-Es) in RAW264 macrophages. By the live-cell imaging of fluorescent protein-fused M-Ras, we found that M-Ras was localized to the membrane of phagocytic cups during the early stage of phagosome formation. Notably, ratiometric image analysis revealed that M-Ras was concentrated in the membrane of forming phagosomes. Moreover, our analysis of M-Ras mutant expression showed that phagosome formation was significantly inhibited in cells expressing GDP-locked mutant M-Ras-S27N. In contrast, the expression of wild-type M-Ras or GTP-locked mutant M-Ras-G22V facilitated the uptake of IgG-Es. These data suggest that M-Ras is a novel component of the FcγR-mediated phagocytic pathway and may regulate phagosome formation in macrophages.