School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK.
Virus Res. 2012 Jan;163(1):269-74. doi: 10.1016/j.virusres.2011.10.011. Epub 2011 Oct 20.
Expression of the rotavirus enterotoxin (NSP4) in transfected monkey kidney cells was found to result in a dramatic re-modeling of the microtubule (MT) network. This important centrosome organized cytoskeletal element was dissolved by expression of NSP4 and re-formed in a ring array at the periphery of the cell, similar to that seen following normal virus infection. Site directed mutagenesis of the N-linked glycosylation sites in NSP4 was employed to show that glycosylation of NSP4 was not required for it to promote changes in the MT network. This result together with experiments using conventional inhibitors indicated that NSP4's ability to cause elevation of intracellular calcium levels was also not necessary to effect the changes in the MT network. Use of the centrosome function inhibitor nocodazole demonstrated that NSP4 based remodeling of the MT network was dominant over the normal organizational role of the centrosome. Finally the remodeling of the MT network was shown not to be linked to cellular apoptosis or necrosis. The potential importance of this newly recognised role for NSP4 in the overall process of intracellular pathogenesis by rotaviruses is discussed.
转染猴肾细胞中轮状病毒肠毒素（NSP4）的表达导致微管（MT）网络发生显著重塑。这种重要的中心体组织细胞骨架元素被 NSP4 的表达溶解，并在细胞外周重新形成环状排列，类似于正常病毒感染后观察到的情况。通过对 NSP4 中 N-连接糖基化位点的定点突变，表明 NSP4 的糖基化对于促进 MT 网络的改变不是必需的。这一结果以及使用常规抑制剂的实验表明，NSP4 引起细胞内钙离子水平升高的能力对于 MT 网络的改变也是不必要的。使用中心体功能抑制剂诺考达唑表明，NSP4 引起的 MT 网络重塑在功能上优于中心体的正常组织作用。最后，证明 MT 网络的重塑与细胞凋亡或坏死无关。讨论了 NSP4 在轮状病毒细胞内发病过程中的这种新识别作用的潜在重要性。
