Progressive Rotavirus Infection Downregulates Redox-Sensitive Transcription Factor Nrf2 and Nrf2-Driven Transcription Units

Figure 7

Cullin 3/Rbx1 complex is dispensable for the downregulation of the Nrf2/ARE pathway during RV infection. (a) MA104 cells were transfected with pcDNSP1 or empty vector (pcDNA6B). Levels of Nrf2, HO-1, and His (NSP1) were checked in the cellular extracts 36 hours after transfection. Relative fold changes of proteins are represented; “” represents comparison with respect to the mock transfected control. (b) pcDNSP1 transfected MA104 cells were infected with RV-SA11 (9 hpi) 36 hours post transfection before assessing Nrf2, HO-1, and His (NSP1) protein levels by SDS-PAGE/immunoblot analyses. Relative fold changes of proteins are represented; “” and “#” represent comparisons with respect to mock transfected mock-infected and pcDNSP1 transfected mock-infected groups, respectively. (c) Steady-state levels of Rbx1 and Cul3 were checked in RV-SA11-infected MA104 cells harvested at indicated time points post infection. Relative fold changes of proteins are represented; “ns” represents comparison with respect to the mock-infected control. (d, e) MA104 cells pretransfected with (d) DN-Cul3 and (e) Rbx1 siRNA for 36 hours were subsequently infected with RV-SA11 for 9 hours. Cellular lysates were further subjected to SDS-PAGE/immunoblot analyses and probed to check protein levels of Nrf2 and HO-1. Expressions of (d) FLAG and (e) Rbx1 were assessed to assure efficient transfection. (d, e) Relative fold changes of proteins are represented; “” and “#” represent comparisons with respect to mock transfected mock-infected and (d) DN-Cul3 and (e) Rbx1 siRNA transfected mock-infected groups, respectively.

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