Colocalization of IFI16 with BrdU genome labeled KSHV in the nucleus, acetylation of IFI16 in the nucleus and cytoplasmic redistribution during <i>de novo</i> KSHV infection of HMVEC-d cells.

<p><b>(A)</b> HMVEC-d cells were infected for 15 and 30 min with BrdU genome labeled KSHV (30 DNA copies/cell), processed for IFA, reacted with anti-IFI16 and anti-BrdU antibodies followed by Alexa Fluor-594/488 secondary antibodies and DAPI (blue). The boxed areas are enlarged. Red arrows: KSHV genome in the cytoplasm (green dots); yellow arrows: cytoplasmic IFI16; white arrows: colocalization of IFI16 with KSHV genome (yellow spots) in the nucleus. 60X magnification. <b>(B)</b> HMVEC-d cells were uninfected (UI) or infected with KSHV for different time points, nuclear and cytoplasmic fractions isolated and western blotted for IFI16. Tubulin and TBP were used as purity markers for cytoplasmic and nuclear fractions, respectively, and as loading controls. <b>(C and D)</b> Equal quantities of whole cell lysate (WCL) proteins from uninfected and KSHV infected (24 h) cells in NETN buffer were immunoprecipitated (IP-ed) with anti-acetylated lysine antibody and western blotted for IFI16 and tubulin (C), and cytoplasmic and nuclear proteins (D) were IP-ed with anti-acetylated lysine antibody and western blotted for IFI16, tubulin and H3. Cytoplasmic and nuclear proteins were western blotted for total H3, tubulin and TBP. <b>(E)</b> HMVEC-d cells were serum-starved without (UT = untreated) or with 1μM p300 inhibitor C-646 for 2 h, uninfected or infected with KSHV for 2 h, washed and incubated in complete medium in the presence or absence of inhibitor for 4 and 24 h. WCL in NETN buffer were IP-ed with anti-acetylated lysine or IFI16 antibodies and western blotted for IFI16. <b>(F)</b> 24 h lysates from (E) were IP-ed with anti-IFI16 and western blotted for acetylated lysine. <b>(G)</b> HMVEC-d cells treated or untreated with C-646 for 2 h were either left uninfected (UI) or infected with KSHV for various time points, nuclear and cytoplasmic fractions isolated and western blotted for IFI16.