AccuPrime Pfx DNA polymerase (Invitrogen) was used for site directed mutagenesis using the QuikChange II Site-directed Mutagenesis protocol from Agilent Technologies. The following murine stem cell virus (MSCV)-based retroviral vectors were used to express Unc93b1, TLR9, TLR7, and TLR3 in cell lines: MSCV-PuromCherry (IRES-PuromycinR-T2A-mCherry), MSCV2.2 (IRES-GFP), MSCV-Thy1.1 (IRES-Thy1.1), and MIGR2 (IRES-hCD2). 3×FLAG (DYKDHDGDYKDHDIDYKDDDDK) was fused to the C-terminus of Unc93b1. TLR9, TLR7, and TLR3 were fused to HA (YPYDVPDYA) at the C-terminal end. TLR7 sequence was synthesized after codon optimization by Invitrogen’s GeneArt Gene Synthesis service as previously described10 (link). TLR9 chimeras of the juxtamembrane and transmembrane regions were previously described4 (link).