The invasion of tobacco mosaic virus RNA induces endoplasmic reticulum stress-related autophagy in HeLa cells

Li, Li; Wang, Li; Xiao, Ruijing; Zhu, Guoguo; Li, Yan; Liu, Changxuan; Yang, Ru; Tang, Zhiqing; Li, Jie; Huang, Wei; Chen, Lang; Zheng, Xiaoling; He, Yuling; Tan, Jinquan

Autophagy is beginning to be recognized as an important player in the life-and-death decisions of the ERS response. The control mechanisms of these processes are not fully understood and are the focus of many ongoing investigations. Several reports have shown that ERS can activate autophagy, and conversely, blocking autophagy can enhance ERS-induced cell death [33] . In recent immunoelectron microscopy studies, Dunn has reported that autophagosomes originating from pre-existing ER acquire lysosomal markers in a stepwise fashion during maturation into autolysosomes. Dunn also classified vacuoles morphologically and cytochemically into two groups: (i) nascent autophagic vacuoles (or autophagosomes) and (ii) degradative autophagic vacuoles (or autolysosomes) [34, 35] . Herein, we showed that the invasion of TMV-RNA not only triggered autophagy, but also induced ERS in HeLa cells. To further elucidate the connection between autophagy and ERS, we examined the morphological changes of the cells using EM.