RHOA-mediated mechanical force generation through Dectin-1
RHOA-mediated mechanical force generation through Dectin-1
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DOI：
10.1242/jcs.236166
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发表时间：
2020-03-01
影响因子：
4
通讯作者：
Neumann, Aaron K.
中科院分区：
文献类型：
--
作者：
Choraghe, Rohan P.;Kolodziej, Tomasz;Neumann, Aaron K.
树突状细胞相关的C型凝集素1(Dectin-1，又称CLEC7A)是一种天然免疫模式识别受体，识别白色念珠菌细胞壁上的β-葡聚糖。免疫细胞对β-葡聚糖的识别导致吞噬、氧化爆发、细胞因子和趋化因子的产生。我们寻找特定的机制来协调Dectin-1下游的吞噬作用，导致肌动蛋白重组和真菌的内化。我们发现，可溶性葡聚糖刺激Dectin-1可导致Dectin-1转基因HEK-293细胞和M1巨噬细胞产生机械力和区域收缩。通过对抑制剂的研究，我们发现这种作用力的产生不依赖于脾酪氨酸激酶(SYK)，但依赖于SRC家族激酶(SFK)，通过RHOA-ROCK-肌球蛋白轻链(MLC)途径介导。我们通过活性分析和应力纤维形成证实了Dectin-1下游RHOA的激活。通过吞噬实验，我们发现了RHOA-ROCK-MLC信号在白念珠菌吞噬过程中的重要性的直接证据。
Dendritic cell-associated C-type lectin 1 (Dectin-1, also known as CLEC7A) is an innate immune pattern recognition receptor that recognizes beta-glucan on the Candida albicans cell wall. Recognition of beta-glucan by immune cells leads to phagocytosis, oxidative burst, cytokine and chemokine production. We looked for specific mechanisms that coordinate phagocytosis downstream of Dectin-1 leading to actin reorganization and internalization of fungus. We found that stimulation of Dectin-1 by soluble li-glucan leads to mechanical force generation and areal contraction in Dectin1-transfected HEK-293 cells and M1 macrophages. With inhibitor studies, we found this force generation is a spleen tyrosine kinase (SYK)-independent, but SRC family kinase (SFK)-dependent process mediated through the RHOA-ROCK-myosin light chain (MLC) pathway. We confirmed activation of RHOA downstream of Dectin-1 using activity assays and stress fiber formation. Through phagocytosis assays, we found direct evidence for the importance of RHOA-ROCK-MLC signaling in the process of phagocytosis of C. albicans.