A role for cytoplasmic PML in cellular resistance to viral infection

McNally BA, Trgovcich J, Maul GG, Liu Y, Zheng P
Source: PLoS ONE
Publication Date: (2008)
Issue: 3(5): e2277
Research Area:
Cancer Research/Cell Biology
Cells used in publication:
Species: human
Tissue Origin: lung
Nucleofector® I/II/2b
PML gene was discovered as a fusion partner with retinoic acid receptor (RAR) alpha in the t(15:17) chromosomal translocation associated with acute promyelocytic leukemia (APL). Nuclear PML protein has been implicated in cell growth, tumor suppression, apoptosis, transcriptional regulation, chromatin remodeling, DNA repair, and anti-viral defense. The localization pattern of promyelocytic leukemia (PML) protein is drastically altered during viral infection. This alteration is traditionally viewed as a viral strategy to promote viral replication. Although multiple PML splice variants exist, we demonstrate that the ratio of a subset of cytoplasmic PML isoforms lacking exons 5 & 6 is enriched in cells exposed to herpes simplex virus-1 (HSV-1). In particular, we demonstrate that a PML isoform lacking exons 5 & 6, called PML Ib, mediates the intrinsic cellular defense against HSV-1 via the cytoplasmic sequestration of the infected cell protein (ICP) 0 of HSV-1. The results herein highlight the importance of cytoplasmic PML and call for an alternative, although not necessarily exclusive, interpretation regarding the redistribution of PML that is seen in virally infected cells.