Anti-EFC antibodies are used in antigen-specific immunodetection in biological samples. The target EFC is a known alias name of the protein regulatory factor X1, encoded by the RFX1 gene in humans. This 979-amino acid residue protein is known to be involved in immune response pathways and the regulation of transcription, among other biological processes. It is localized to the nucleus of the cell. It is reported to be widely expressed in many tissue types.