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Porcine circovirus type 2 induces autophagy via the AMPK/ERK/TSC2/mTOR signaling pathway in PK-15 cells.

ABSTRACT: Porcine circovirus type 2 (PCV2) uses autophagy machinery to enhance its replication in PK-15 cells. However, the underlying mechanisms are unknown. By the use of specific inhibitors, RNA interference, and coimmunoprecipitation, we show that PCV2 induces autophagy in PK-15 cells through a pathway involving the kinases AMP-activated protein kinase (AMPK) and extracellular signal-regulated kinase 1/2 (ERK1/2), the tumor suppressor protein TSC2, and the mammalian target of rapamycin (mTOR). AMPK and ERK1/2 positively regulate autophagy through negative control of the mTOR pathway by phosphorylating TSC2 in PCV2-infected PK-15 cells. Thus, PCV2 might induce autophagy via the AMPK/ERK/TSC2/mTOR signaling pathway in the host cells, representing a pivotal mechanism for PCV2 pathogenesis.

SUBMITTER: Zhu B

PROVIDER: S-EPMC3486458 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Porcine circovirus type 2 induces autophagy via the AMPK/ERK/TSC2/mTOR signaling pathway in PK-15 cells.

Zhu Binglin B Zhou Yingshan Y Xu Fei F Shuai Jiangbing J Li Xiaoliang X Fang Weihuan W

Journal of virology 20120822 22

Porcine circovirus type 2 (PCV2) uses autophagy machinery to enhance its replication in PK-15 cells. However, the underlying mechanisms are unknown. By the use of specific inhibitors, RNA interference, and coimmunoprecipitation, we show that PCV2 induces autophagy in PK-15 cells through a pathway involving the kinases AMP-activated protein kinase (AMPK) and extracellular signal-regulated kinase 1/2 (ERK1/2), the tumor suppressor protein TSC2, and the mammalian target of rapamycin (mTOR). AMPK an ...[more]

PMID: 22915817

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