Key Points
- Determine the specific transcription factor deficient in host cells following poliovirus-mediated inhibition of RNA polymerase II transcription.
- Harvested whole-cell extracts from poliovirus-infected and mock-infected HeLa cells at 3 hours postinfection.
- Assayed in vitro transcription reconstitution from the adenovirus major late promoter across three chromatographic fractionation steps.
- Compared heat inactivation kinetics and specific activity between chromatographic fractions from infected and uninfected cells.
- Transcription-restoring activity from mock-infected extracts copurified alongside transcription factor TFIID across three chromatographic steps.
- Reconstituted transcription reactions demonstrated a fourfold decrease in specific activity of the TFIID-containing fraction from infected cells relative to mock-infected controls.
- Inactivating heat kinetics of pure TFIID matched the kinetics of the transcription-restoring factor, confirming TFIID inactivation occurs as an early event in infection.
Structured PICO
PPopulationHeLa cells in vitro
IInterventionPoliovirus infection
CComparatorMock-infected cells
OOutcomeInhibition of host cell RNA polymerase II-mediated transcription and TFIID activity
Inactivation of transcription factor TFIID is an early event in the inhibition of host cell RNA polymerase II transcription by poliovirus.