A protein repressing GLI's transcription factor activity when SMO signaling is inactive. Upon ligand binding to the upstream receptor PTC (Patched) GLI dissociates from SUFU and activates transcription of hedgehog-target genes. In mammals it consists of SUFU and one of the GLI family proteins.
Comment:
An example of this is SUFU in human (Q9UMX1) in PMID:24311597 (inferred from direct assay).