Corepressor targeting diverse transcription regulators. Hairy-interacting protein required for embryonic segmentation and hairy-mediated transcriptional repression. Homodimer. Interacts with hairy (h), knirps (kni), snail (sna), and Enhancer of split m-delta (HLHm-delta). Complex may be involved in transcriptional repression. Interacts also with adenovirus E1A protein. A number of isoforms are produced. Expressed both maternally and zygotically. Zygotic expression is highest in pupae. Belongs to the D-isomer specific 2-hydroxyacid dehydrogenase family.