Homeobox protein Hox-C11 (HOXC11) is a key regulatory protein. Encoded by the HOXC11 gene, it's a member of the homeobox transcription factor family. It functions importantly in embryonic morphogenesis and organogenesis, governing the spatial and temporal development of tissues and organs by binding to specific DNA sequences and regulating gene expression.Besides,Huntingtin (HTT) has been identified as an interactor of HOXC11, thus a functional binding ELISA assay was conducted to detect the interaction of recombinant human HOXC11 and recombinant human HTT. Briefly, biotin-linked HOXC11 were diluted serially in PBS, with 0.01% BSA (pH 7.4). Duplicate samples of 100μl were then transferred to HTT-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 HOXC11 and HTT was shown in Figure 1, the EC50?for this effect is 0.085ug/mL.