A novel anti-aldolase C antibody specifically interacts with residues 85-102 of the protein

Aldolase C is a brain-specific glycolytic isozyme whose predicted moonlighting functions are obscure. This issue can be addressed using molecular tools that discriminate the protein from the homologous, ubiquitous paralog aldolase A. The anti-aldolase C antibodies currently available are polyclonal and not highly specific. We have obtained a novel monoclonal antibody (9F) against human aldolase C, characterized its isoform specificity and tested its performance. First, we investigated the specificity of 9F for aldolase C. Then, using bioinformatic tools coupled to molecular cloning and chemical synthesis approaches, we produced truncated human aldolase C fragments, and assessed 9F binding to these fragments by western blot and ELISA assays. This strategy revealed that residues 85-102 harbour the epitope-containing region recognized by 9F. The efficiency of 9F was demonstrated also for immunoprecipitation assays. Finally, surface plasmon resonance revealed that the protein has a high affinity toward the epitope-containing peptide. Taken together, our findings show that epitope recognition is sequence-driven and is independent of the three-dimensional structure. In conclusion, given its specific molecular interaction, 9F is a novel and powerful tool to investigate aldolase C’s moonlighting functions in the brain.