Adapter molecule that plays a key role in the activation of pro-inflammatory NF-kappa-B signaling following detection of bacterial pathogen-associated molecular pattern metabolites (PAMPs) (PubMed:11798190). Promotes activation of an innate immune response by inducing the oligomerization and polyubiquitination of TRAF6, which leads to the activation of TAK1 and IKK through a proteasome-independent mechanism (By similarity). TIFA-dependent innate immune response is triggered by ADP-D-glycero-beta-D-manno-heptose (ADP-Heptose), a potent PAMP present in all Gram-negative and some Gram-positive bacteria: ADP-Heptose is recognized by ALPK1, which phosphorylates TIFA at Thr-9, leading to TIFA homooligomerization and subsequent activation of pro-inflammatory NF-kappa-B signaling (By similarity). Homooligomer; homooligomerizes following phosphorylation at Thr-9 (By similarity). Interacts with IRAK1, TRAF2 and TRAF6 (PubMed:11798190). Interacts with TIFAB; binding to TIFAB inhibits TRAF6 activation, possibly by inducing a conformational change in TIFA (By similarity). Interacts with ZCCHC11; binding to ZCCHC11 suppresses the TRAF6-dependent activation of NF-kappa-B (By similarity). Colocalizes with lysosomal marker LAMP2 following homooligomerization and subsequent activation. Highly expressed in the spleen and at lower levels in heart, brain, lung, liver, kidney and testes. The FHA domain recognizes and binds phosphorylated Thr-9, promoting homooligomerization and subsequent activation of NF-kappa-B. Phosphorylated at Thr-9 following detection of ADP-D-glycero-beta-D-manno-heptose (ADP-Heptose) by ALPK1. Phosphorylation at Thr-9 by ALPK1 leads to the formation of an intermolecular binding between the FHA domain and phosphorylated Thr-9, promoting TIFA oligomerization and TIFA-mediated NF-kappa-B activation. Belongs to the TIFA family.