indian hedgehog protein; IHH; HHG-2; contains: indian hedgehog protein N-product, indian hedgehog protein C-product (IHH)

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Function

intercellular signal essential for a variety of patterning events during development
binds to the patched receptor (PTC), which functions in association with smoothened (SMO), to activate transcription of target genes
implicated in endochondral ossification
- may regulate the balance between growth & ossification of developing bones
induces expression of parathyroid hormone-related protein (PTHRP) (putative)
the C-terminal domain displays an autoproteolysis activity & a cholesterol transferase activity
- both activities result in cleavage of the full-length protein & covalent attachment of a cholesterol moiety to the C-terminal of the newly generated N-terminal fragment (N-product)
the N-product is the active species in both local & long-range signaling
the C-product has no signaling activity (putative)
cholesterylation is required for N-product targeting to lipid rafts & multimerization (putative)
palmitoylated; N-palmitoylation is required for N-product multimerization & full activity

indian hedgehog protein N-product:
- cell membrane; lipid-anchor; extracellular side (putative)
- N-terminal peptide remains associated with the cell surface (putative)
indian hedgehog protein C-product:
- secreted, extracellular space (putative)
- the C-terminal peptide diffuses from the cell (putative)