Journal: The Journal of Biological Chemistry

Article Title: Inhibitor of ?B Kinase ? (IKK?), STAT1, and IFIT2 Proteins Define Novel Innate Immune Effector Pathway against West Nile Virus Infection *

doi: 10.1074/jbc.M111.285205

Figure Lengend Snippet: Virus infection induces delayed STAT1 Ser-708 phosphorylation. A, WT or IKKϵ−/− MEFs were mock-stimulated or stimulated with 100IU/ml IFN-β. Protein lysate was collected 16 h post-IFN stimulation and immunoblotted using p-STAT1 Ser-708, p-STAT1 Ser-727, p-STAT1 Tyr-701, and total STAT1 antibodies. B and C, Sendai and WNV virus infections induce STAT1 Ser-708 phosphorylation. HEK293 cells were infected with 100 HA units/ml SenV (B) or West Nile virus strain Madagascar (WNV-MAD) (C) at an m.o.i. of 1. At the indicated times following infection, protein lysates were collected and immunoblotted for p-STAT1 Ser-708, p-STAT1 Tyr-701, total STAT1, p-IRF-3, total IRF-3, IFIT1, and SenV or WNV. Tubulin and GAPDH were used as loading controls.

Article Snippet: Affinity-purified rabbit polyclonal anti-STAT1 Ser-708 antibody was generated by repeat-immunization with the STAT1 Ser-708 phospho-specific peptide (YIKTELI{pS}VSEVHP, amino acids 701–714) (GenScript).

Techniques: Infection

Journal: The Journal of Biological Chemistry

Article Title: Inhibitor of ?B Kinase ? (IKK?), STAT1, and IFIT2 Proteins Define Novel Innate Immune Effector Pathway against West Nile Virus Infection *

doi: 10.1074/jbc.M111.285205

Figure Lengend Snippet: Type I, type II, and type III IFNs induce STAT1 Ser-708 phosphorylation. 2fTGH cells were mock-treated or treated with 100 IU/ml IFN-β (A) or 50 ng/ml IFN-γ (B). C, PH5CH8 cells were mock-treated (lane 1), treated with 100 ng/ml IFN-λ1 (lanes 2-6), or 100 IU/ml IFN-β (lanes 7-9). Protein lysate was collected at respective time points following IFN treatment and immunoblotted for p-STAT1 Ser-708, p-STAT1 Tyr-701, p-STAT1 Ser-727, total STAT1, ADAR1, and IFIT1.

Article Snippet: Affinity-purified rabbit polyclonal anti-STAT1 Ser-708 antibody was generated by repeat-immunization with the STAT1 Ser-708 phospho-specific peptide (YIKTELI{pS}VSEVHP, amino acids 701–714) (GenScript).

Techniques:

Journal: The Journal of Biological Chemistry

Article Title: Inhibitor of ?B Kinase ? (IKK?), STAT1, and IFIT2 Proteins Define Novel Innate Immune Effector Pathway against West Nile Virus Infection *

doi: 10.1074/jbc.M111.285205

Figure Lengend Snippet: Signaling through IFNAR is required for STAT1 Ser-708 phosphorylation following type I IFN treatment or virus infection. WT, IRF-3−/−, or IFNAR−/− (A) and parental 2fTGH cells or their derivative U5A cells (which lack IFNAR) (B) were infected with WNV-MAD at an m.o.i. of 1. Protein lysates were collected at the indicated time points and immunoblotted for p-STAT1 Ser-708, p-STAT1 Tyr-701, p-STAT1 Ser-727, total STAT1, p-IRF-3, total IRF-3, and WNV. C and D, the same cells were also mock-stimulated or stimulated with 100 IU/ml IFN-β for 6 or 16 h. Protein lysates were collected at the indicated time points and immunoblotted for p-STAT1 Ser-708, p-STAT1 Tyr-701, p-STAT1 Ser-727, total STAT1, p-IRF-3, total IRF-3, IFIT2, IFIT3, and IFIT1. Asterisk, nonspecific band.

Article Snippet: Affinity-purified rabbit polyclonal anti-STAT1 Ser-708 antibody was generated by repeat-immunization with the STAT1 Ser-708 phospho-specific peptide (YIKTELI{pS}VSEVHP, amino acids 701–714) (GenScript).

Techniques: Infection

Journal: The Journal of Biological Chemistry

Article Title: Inhibitor of ?B Kinase ? (IKK?), STAT1, and IFIT2 Proteins Define Novel Innate Immune Effector Pathway against West Nile Virus Infection *

doi: 10.1074/jbc.M111.285205

Figure Lengend Snippet: STAT1 Ser-708 phosphorylation requires de novo protein synthesis, STAT1 tyrosine dephosphorylation, and nuclear export. A, 2fTGH cells were mock-treated (-CHX, lanes 1-5) or treated with CHX (+CHX, lanes 6-11) to block protein synthesis. At 30 min (lanes 6-10) or 16 h (lane 11) following CHX treatment, cells were mock-stimulated (M) or stimulated with IFN-β. Cells were harvested at 10 min as well as 1, 6, and 16 h post-IFN stimulation and immunoblotted to detect p-STAT1 Ser-708, p-STAT1 Tyr-701, total STAT1, ISG15, and IFIT1. B, 2fTGH cells were not treated (NT, lanes 1-3), pretreated with 100 nm LMB (lanes 4-6), or 50 mm pervanadate (Van, lanes 7-9) 1 h before mock stimulation or stimulation with 100 IU/ml IFN-β. Cells were harvested at 1 and 16 h post-stimulation. Immunoblot analysis was performed using p-STAT1 Ser-708, p-STAT1 Tyr-701, p-STAT1 Ser-727, total STAT1, ADAR1, and IFIT1 antibodies.

Article Snippet: Affinity-purified rabbit polyclonal anti-STAT1 Ser-708 antibody was generated by repeat-immunization with the STAT1 Ser-708 phospho-specific peptide (YIKTELI{pS}VSEVHP, amino acids 701–714) (GenScript).

Techniques: De-Phosphorylation Assay, Blocking Assay, Western Blot

Journal: The Journal of Biological Chemistry

Article Title: Inhibitor of ?B Kinase ? (IKK?), STAT1, and IFIT2 Proteins Define Novel Innate Immune Effector Pathway against West Nile Virus Infection *

doi: 10.1074/jbc.M111.285205

Figure Lengend Snippet: IKKϵ mediates IFIT2 expression and protection against WNV pathogenesis in vivo. WT Bl6 and IKKϵ−/− mice were mock-infected (PBS only) or infected with 103 pfu of WNV-MAD subcutaneously through footpad injection. A, mice were monitored and scored daily for clinical symptoms over 17 days. Clinical scores from four representative mice per group were graphed. B, spleens from WT or IKKϵ−/− mice, mock-infected or infected with WNV-MAD, were collected at days 4, 6, and 12 post-infection. Protein lysates were extracted by homogenizing spleens with radioimmune precipitation assay buffer and immunoblotted using p-STAT1 Ser-708, p-STAT1 Tyr-701, p-STAT1 Ser-727, total STAT1, IFIT2, IFIT1, WNV, and IKKϵ antibodies. The immunoblot analysis panel is a representative from four mice per infection group.

Article Snippet: Affinity-purified rabbit polyclonal anti-STAT1 Ser-708 antibody was generated by repeat-immunization with the STAT1 Ser-708 phospho-specific peptide (YIKTELI{pS}VSEVHP, amino acids 701–714) (GenScript).

Techniques: Expressing, In Vivo, Infection, Injection, Western Blot

Journal: The Journal of Biological Chemistry

Article Title: Inhibitor of ?B Kinase ? (IKK?), STAT1, and IFIT2 Proteins Define Novel Innate Immune Effector Pathway against West Nile Virus Infection *

doi: 10.1074/jbc.M111.285205

Figure Lengend Snippet: A model illustrating that early and late ISGs induction is regulated by multiple STAT1 posttranslational modifications. 1, the canonical JAK-STAT signaling is activated following type I IFN binding to its receptor, which results in STAT1 Tyr-701 phosphorylation, ISGF3 formation, and its nuclear translocation. ISGF3 binding to the ISRE element induces transcription of ISGs. 2, chromatin-bound STAT1 can be phosphorylated by MAPK at residue Ser-727, which induces its sumoylation. 3 and 4, nuclear STAT1 is also acetylated by histone acetyltransferase (HAT) CREB-binding protein (CBP), resulting in recruitment of TCP1, which catalyzes STAT1 tyrosine dephosphorylation. Sumoylated-acetylated STAT1 cycles back to the cytoplasm, and both modifications render STAT1 unable to be further tyrosine-phosphorylated. 5 and 6, type I IFN signaling and unknown IFN-stimulated factor(s) activate IKKϵ phosphorylation of STAT1 Ser-708. 7, STAT1 molecules phosphorylated at Ser-708 can enter the nucleus and induce expression of a specific ISG subset. pY, tyrosine phosphorylation; pS, serine phosphorylation; Ac, acetylation; Su, sumoylation.

Article Snippet: Affinity-purified rabbit polyclonal anti-STAT1 Ser-708 antibody was generated by repeat-immunization with the STAT1 Ser-708 phospho-specific peptide (YIKTELI{pS}VSEVHP, amino acids 701–714) (GenScript).

Techniques: Binding Assay, Translocation Assay, De-Phosphorylation Assay, Expressing

Journal: PLoS Pathogens

Article Title: RIG-I-like receptor activation by dengue virus drives follicular T helper cell formation and antibody production

doi: 10.1371/journal.ppat.1006738

Figure Lengend Snippet: DCs were mock-treated or infected with DENV for 30 (E,F,G,H,I), 32 (B,C,D,K) or 48 hours (A) in the presence or absence of blocking antibodies directed against IFNα/βR (C),IFNLR (D) or after MAVS, RIG-I, MDA5, IKKε, or IRF9 silencing (A,B,K) and secretion of IL-27 into the supernatant was measured by ELISA (A) or mRNA expression was analyzed using real-time PCR (B,C,D,K), normalized to GAPDH and set at 1 in DENV-infected samples treated with control siRNA (B,K) or isotype antibody (C,D). (E-G) STAT1 phosphorylation at Ser708 or Ser727 in mock-treated or DENV-infected DCs was analyzed by flow cytometry (E,F) or immunoblot (G) using phospho-specific antibodies. Total STAT1 served as loading control in (G). Relative mean fluorescent intensity (MFI) shown in (F). (H) Confocal imaging of DNA (Hoechst, blue), DENV Envelope protein (E protein, green) or IRF9 (red) in mock-treated or DENV-infected DCs 30 hours post infection. White arrowheads indicate cells with nuclear IRF9. (I) Immunoblot for IRF9 of nuclear (NE) or cytoplasmic (CE) extracts of DCs infected with DENV at indicated times. β-actin served as loading control. (J) Similar as in (I) but IRF9 levels in nuclear extracts were measured by ELISA. Data are representative of at least five (E), four (H), or two (A,G,I) independent experiments with different donors (mean ± s.d. of duplicates in A) or are collated data (mean ± s.d.) of four (D,F,K),three (B,C) or two (J) different donors. ** P <0.01, * P <0.05 (student’s t-test).

Article Snippet: For immunoblot, whole cell extracts were prepared using Ripa lysis buffer (Cell Signaling Technology) and protein were resolved by SDS-PAGE and detected with anti-TBK1 Ser172 (1:1000, 5483S, Cell Signaling) anti-IKKε Ser172 (1:1000, 06–1340, Millipore), anti-STAT1 Ser708 (1:1000, provided by M. Gale, Jr, University of Washington School of Medicine, Seattle, WA, (Perwitasari et al., 2011) or anti-STAT1 Ser727 (1:1000, 9177; Cell Signaling).

Techniques: Infection, Blocking Assay, Enzyme-linked Immunosorbent Assay, Expressing, Real-time Polymerase Chain Reaction, Control, Phospho-proteomics, Flow Cytometry, Western Blot, Imaging