Homeobox protein Hox-A13 (HOXA13)?is a transcription factor encoded by the HOXA13 gene, part of the HOX gene family. It plays a crucial role in limb and urogenital development by regulating gene expression during embryonic development. Mutations in HOXA13 are associated with developmental disorders such as Hand-Foot-Genital Syndrome (HFGS).Besides,Absent In Melanoma 2 (AIM2) has been identified as an interactor of HOXA13, thus a functional binding ELISA assay was conducted to detect the interaction of recombinant human HOXA13 and recombinant human AIM2. Briefly, biotin-linked HOXA13 were diluted serially in PBS, with 0.01% BSA (pH 7.4). Duplicate samples of 100μl were then transferred to AIM2-coated microtiter wells and incubated for 1h at 37℃. Wells were washed with PBST 3 times and incubation with Streptavidin-HRP for 30min, then wells were aspirated and washed 5 times. With the addition of substrate solution, wells were incubated 15-25 minutes at 37℃. Finally, add 50μl stop solution to the wells and read at 450nm immediately. The binding activity of HOXA13 and AIM2 was shown in Figure 1, the EC50?for this effect is 0.086ug/mL.