Enhancement of Autophagy during Lytic Replication by the Kaposi’s Sarcoma-Associated Herpesvirus Replication and Transcription Activator

Authors

Hui-Ju Wen, University of Nebraska-Lincoln
Zhilong Yang, University of Nebraska-Lincoln
You Zhou, University of Nebraska-LincolnFollow
Charles Wood, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

2010

Citation

JOURNAL OF VIROLOGY, Aug. 2010, p. 7448–7458 Vol. 84, No. 15

Comments

Copyright © 2010, American Society for Microbiology. All Rights Reserved.

Abstract

Autophagy is one of two major degradation systems in eukaryotic cells. The degradation mechanism of autophagy is required to maintain the balance between the biosynthetic and catabolic processes and also contributes to defense against invading pathogens. Recent studies suggest that a number of viruses can evade or subvert the host cell autophagic pathway to enhance their own replication. Here, we investigated the effect of autophagy on the KSHV (Kaposi’s sarcoma-associated herpesvirus) life cycle. We found that the inhibition of autophagy reduces KSHV lytic reactivation from latency, and an enhancement of autophagy can be detected during KSHV lytic replication. In addition, RTA (replication and transcription activator), an essential viral protein for KSHV lytic reactivation, is able to enhance the autophagic process, leading to an increase in the number of autophagic vacuoles, an increase in the level of the lipidated LC3 protein, and the formation of autolysosomes. Moreover, the inhibition of autophagy affects RTA-mediated lytic gene expression and viral DNA replication. These results suggest that RTA increases autophagy activation to facilitate KSHV lytic replication. This is the first report demonstrating that autophagy is involved in the lytic reactivation of KSHV.