Hedgehog proteins are a family of secreted signal molecules required for embryonic cell differentiation. They are synthesised as inactive precursors with an N-terminal signalling domain linked to a C-terminal autoprocessing domain. The three-dimensional structure of the autolytic domain of the hedgehog protein of shows similarity with the beta-strand core of intein splicing domains. It has hence been termed the hint (Hedgehog/Intein) domain.This entry represents the N-terminal region of the hint domain.