F-actin organization and target constriction during primary macrophage phagocytosis is balanced by competing activity of myosin-I and myosin-II.
F-actin organization and target constriction during primary macrophage phagocytosis is balanced by competing activity of myosin-I and myosin-II.
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DOI：
10.1091/mbc.e22-06-0210
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发表时间：
2022-12-01
影响因子：
3.3
通讯作者：
Krendel, Mira
中科院分区：
文献类型：
--
作者：
Barger, Sarah R.;Vorselen, Daan;Gauthier, Nils C.;Theriot, Julie A.;Krendel, Mira
吞噬作用需要肌动蛋白细胞骨架的快速重塑，用于膜突起的延伸和力的产生，以最终驱动靶标的吞噬。吞噬作用的详细机制几乎只在永生化细胞系中进行了研究。在这里，我们利用高分辨率成像和新的生物物理方法来确定的结构和机械功能的吞噬原代骨髓来源的巨噬细胞。我们发现，这些原代细胞的签名行为是不同的巨噬细胞样细胞系，具体来说，它是温和的，只有弱的目标收缩和适度的极化内的F-肌动蛋白分布的吞噬杯。我们发现长尾肌球蛋白1 e/f对该组织至关重要。myo 1 e/f的缺乏会导致F-肌动蛋白定位的显著变化，减少吞噬杯基部的F-肌动蛋白，并增强杯边缘的F-肌动蛋白介导的收缩。令人惊讶的是，这些变化几乎可以完全逆转后，抑制另一种肌球蛋白马达蛋白，肌球蛋白-II。因此，我们表明，吞噬杯的生物力学和大规模的组织是通过肌球蛋白-Ie/f和肌球蛋白-II的竞争性贡献受到严格调控。
Phagocytosis requires rapid remodeling of the actin cytoskeleton for extension of membrane protrusions and force generation to ultimately drive the engulfment of targets. The detailed mechanisms of phagocytosis have almost exclusively been studied in immortalized cell lines. Here, we make use of high-resolution imaging and novel biophysical approaches to determine the structural and mechanical features of phagocytosis by primary bone marrow–derived macrophages. We find that the signature behavior of these primary cells is distinct from macrophage-like cell lines; specifically, it is gentle, with only weak target constriction and modest polarization of the F-actin distribution inside the phagocytic cup. We show that long-tailed myosins 1e/f are critical for this organization. Deficiency of myo1e/f causes dramatic shifts in F-actin localization, reducing F-actin at the phagocytic cup base and enhancing F-actin–mediated constriction at the cup rim. Surprisingly, these changes can be almost fully reverted upon inhibition of another myosin motor protein, myosin-II. Hence, we show that the biomechanics and large-scale organization of phagocytic cups is tightly regulated through competing contributions from myosin-Ie/f and myosin-II.