Quantitative Proteomic Analysis Reveals That Transmissible Gastroenteritis Virus Activates the JAK-STAT1 Signaling Pathway

Transmissible
gastroenteritis virus (TGEV), a porcine enteropathogenic
coronavirus, causes lethal watery diarrhea and severe dehydration
in piglets. In this study, liquid chromatography–tandem mass
spectrometry coupled to isobaric tags for relative and absolute quantification
labeling was used to quantitatively identify differentially expressed
cellular proteins after TGEV infection in PK-15 cells. In total, 162
differentially expressed cellular proteins were identified, including
60 upregulated proteins and 102 downregulated proteins. These differentially
expressed proteins were involved in the cell cycle, cellular growth
and proliferation, the innate immune response, etc. Interestingly,
many upregulated proteins were associated with interferon signaling,
especially signal transducer and activator of transcription 1 (STAT1)
and interferon-stimulated genes (ISGs). Immunoblotting and real-time
quantitative reverse transcription polymerase chain reaction demonstrated
that TGEV infection induces STAT1 phosphorylation and nuclear translocation,
as well as ISG expression. This study for the first time reveals that
TGEV induces interferon signaling from the point of proteomic analysis.