Graf1 controls the growth of human parainfluenza virus type 2 through inactivation of RhoA signaling.
Graf1 controls the growth of human parainfluenza virus type 2 through inactivation of RhoA signaling.
复制标题
Graf1 通过 RhoA 信号传导失活来控制 2 型人类副流感病毒的生长。
DOI：
10.1128/jvi.01471-16
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发表时间：
2016
影响因子：
5.4
通讯作者：
Nishio M
中科院分区：
文献类型：
--
作者：
Ohta K;Goto H;Matsumoto Y;Yumine N;Tsurudome M;Nishio M
Rho GTP 酶参与多种细胞活动，并受鸟嘌呤核苷酸交换因子和 GTP 酶激活蛋白 (GAP) 调节。我们发现溶血磷脂酸激活 Rho GTP 酶可促进人副流感病毒 2 型 (hPIV-2) 的生长。此外，hPIV-2感染会引起RhoA（一种Rho GTP酶）的激活。我们假设 Graf1（也称为 ARHGAP26）是一种 GAP，通过控制 RhoA 信号传导来调节 hPIV-2 的生长。免疫荧光分析表明，hPIV-2 感染改变了 Graf1 的定位，从细胞质内的均匀分布改变为颗粒内。 Graf1 与 hPIV-2 P、NP 和 L 蛋白共定位。 Graf1 通过 N 端共同区域与 P 和 V 蛋白相互作用，而 Graf1 的 C 端 Src 同源 3 结构域区域对于这些相互作用非常重要。在组成型表达Graf1的HEK293细胞中，hPIV-2生长受到抑制，并且在hPIV-2感染期间未观察到RhoA激活。相比之下，Graf1 敲除可恢复 hPIV-2 生长和 RhoA 激活。 hPIV-2 P 和 V 蛋白的过度表达增强了 hPIV-2 诱导的 RhoA 激活。这些结果共同表明，hPIV-2 P 和 V 蛋白通过与 Graf1 结合增强 hPIV-2 生长，而 Graf1 通过 RhoA 失活抑制 hPIV-2 生长。 重要性 hPIV-2 的稳健生长需要 Rho 激活。 hPIV-2 感染会导致 RhoA 激活，而 Graf1 会抑制 RhoA 激活。 Graf1 与 hPIV-2 感染细胞中的病毒 RNP (vRNP) 共定位。我们发现 Graf1 与 hPIV-2 P 和 V 蛋白相互作用。我们还确定了这些蛋白质中对于这种相互作用很重要的区域。 hPIV-2 P 和 V 蛋白通过与 Graf1 结合增强 hPIV-2 生长，而 Graf1 通过 RhoA 失活抑制 hPIV-2 生长。
Rho GTPases are involved in a variety of cellular activities and are regulated by guanine nucleotide exchange factors and GTPase-activating proteins (GAPs). We found that the activation of Rho GTPases by lysophosphatidic acid promotes the growth of human parainfluenza virus type 2 (hPIV-2). Furthermore, hPIV-2 infection causes activation of RhoA, a Rho GTPase. We hypothesized that Graf1 (also known as ARHGAP26), a GAP, regulates hPIV-2 growth by controlling RhoA signaling. Immunofluorescence analysis showed that hPIV-2 infection altered Graf1 localization from a homogenous distribution within the cytoplasm to granules. Graf1 colocalized with hPIV-2 P, NP, and L proteins. Graf1 interacts with P and V proteins via their N-terminal common region, and the C-terminal Src homology 3 domain-containing region of Graf1 is important for these interactions. In HEK293 cells constitutively expressing Graf1, hPIV-2 growth was inhibited, and RhoA activation was not observed during hPIV-2 infection. In contrast, Graf1 knockdown restored hPIV-2 growth and RhoA activation. Overexpression of hPIV-2 P and V proteins enhanced hPIV-2-induced RhoA activation. These results collectively suggested that hPIV-2 P and V proteins enhanced hPIV-2 growth by binding to Graf1 and that Graf1 inhibits hPIV-2 growth through RhoA inactivation.IMPORTANCERobust growth of hPIV-2 requires Rho activation. hPIV-2 infection causes RhoA activation, which is suppressed by Graf1. Graf1 colocalizes with viral RNP (vRNP) in hPIV-2-infected cells. We found that Graf1 interacts with hPIV-2 P and V proteins. We also identified regions in these proteins which are important for this interaction. hPIV-2 P and V proteins enhanced the hPIV-2 growth via binding to Graf1, while Graf1 inhibited hPIV-2 growth through RhoA inactivation.