PKCδ stimulates macropinocytosis via activation of SSH1-cofilin pathway.
PKCδ stimulates macropinocytosis via activation of SSH1-cofilin pathway.
复制标题
DOI：
10.1016/j.cellsig.2018.09.018
复制
发表时间：
2019-01
影响因子：
4.8
通讯作者：
Csányi G
中科院分区：
文献类型：
--
作者：
Singla B;Lin HP;Ghoshal P;Cherian-Shaw M;Csányi G
巨胞饮作用是一种肌动蛋白依赖的内吞机制，介导细胞外液和相关溶质内化到细胞内。本研究旨在确定特定的蛋白激酶C（PKC）异构体（S）和下游效应调节肌动蛋白动力学在巨胞饮。我们利用各种细胞和分子生物学技术，药理学抑制剂和转基因小鼠研究介导巨噬细胞巨胞饮的信号机制。qRT-PCR实验确定PKCδ是巨噬细胞中主要的PKC亚型。FITC-葡聚糖内化的扫描电子显微镜和流式细胞术分析证实了PKCδ在佛波酯和肝细胞生长因子（HGF）诱导的巨胞饮中的功能作用。Western blot分析表明佛波酯和HGF通过PKCδ刺激巨噬细胞中弹弓磷酸酶同源物1（SSH 1）的活化并诱导cofilin Ser-3去磷酸化。SSH 1沉默抑制cofilin去磷酸化和巨胞饮刺激。有趣的是，我们还发现巨噬细胞与BMS-5（一种LIM激酶的有效抑制剂）一起孵育不会刺激巨胞饮。总之，本研究的结果证实了一种以前未鉴定的机制，即PKCδ通过激活SSH 1和cofilin去磷酸化刺激膜皱褶形成和巨胞饮。本研究的结果可能有助于更好地了解在巨噬细胞巨胞饮的调节机制。
Macropinocytosis is an actin-dependent endocytic mechanism mediating internalization of extracellular fluid and associated solutes into cells. The present study was designed to identify the specific protein kinase C (PKC) isoform(s) and downstream effectors regulating actin dynamics during macropinocytosis. We utilized various cellular and molecular biology techniques, pharmacological inhibitors and genetically modified mice to study the signaling mechanisms mediating macropinocytosis in macrophages. The qRT-PCR experiments identified PKCδ as the predominant PKC isoform in macrophages. Scanning electron microscopy and flow cytometry analysis of FITC-dextran internalization demonstrated the functional role of PKCδ in phorbol ester- and hepatocyte growth factor (HGF)-induced macropinocytosis. Western blot analysis demonstrated that phorbol ester and HGF stimulate activation of slingshot phosphatase homologue 1 (SSH1) and induce cofilin Ser-3 dephosphorylation via PKCδ in macrophages. Silencing of SSH1 inhibited cofilin dephosphorylation and macropinocytosis stimulation. Interestingly, we also found that incubation of macrophages with BMS-5, a potent inhibitor of LIM kinase, does not stimulate macropinocytosis. In conclusion, the findings of the present study demonstrate a previously unidentified mechanism by which PKCδ via activation of SSH1 and cofilin dephosphorylation stimulates membrane ruffle formation and macropinocytosis. The results of the present study may contribute to a better understanding of the regulatory mechanisms during macrophage macropinocytosis.
登录
查看更多内容
影响因子：
14.8
作者：
通讯作者：
--
影响因子：
21.3
作者：
Eiseler T;Döppler H;Yan IK;Kitatani K;Mizuno K;Storz P
通讯作者：
Storz P
影响因子：
4
作者：
Hoeller, Oliver;Bolourani, Parvin;Kay, Robert R.
通讯作者：
Kay, Robert R.
影响因子：
4
作者：
Bryant, David M.;Kerr, Markus C.;Stow, Jennifer L.
通讯作者：
Stow, Jennifer L.
影响因子：
6.4
作者：
Aleksandrowicz, Paulina;Marzi, Andrea;Schnittler, Hans-Joachim
通讯作者：
Schnittler, Hans-Joachim