The function of SHH (sonic hedgehog signaling molecule, ENSG00000164690) is as follows. [Sonic hedgehog protein]: Precursor of sonic hedgehog, a morphogen that activates the smoothened signaling pathway, and which is essential for a variety of patterning events during development (PubMed:29954986, PubMed:29995851, PubMed:30139912, PubMed:31127104, PubMed:31548691). The C-terminal part of the precursor displays an autoproteolysis and a cholesterol transferase activity, resulting (1) in the cleavage of the full-length protein into two parts, Sonic hedgehog protein N-product and C-product (ShhN and ShhC, respectively) and (2) covalent attachment of a cholesterol moiety to the C-terminus of the newly generated ShhN (By similarity). Both autoproteolysis and a cholesterol transferase activities occur in the endoplasmic reticulum (By similarity). Following additional lipidation, ShhN acts as a morphogen, while ShhC is degraded in the endoplasmic reticulum (By similarity). {ECO:0000250|UniProtKB:Q62226, ECO:0000269|PubMed:29954986, ECO:0000269|PubMed:29995851, ECO:0000269|PubMed:30139912, ECO:0000269|PubMed:31127104, ECO:0000269|PubMed:31548691}. [Sonic hedgehog protein N-product]: The dually lipidated sonic hedgehog protein N-product (ShhN) is a morphogen that activates the smoothened signaling pathway, and which is essential for a variety of patterning events during development (PubMed:10753901, PubMed:24522195, PubMed:24863049, PubMed:29995851, PubMed:30139912, PubMed:31127104, PubMed:31548691, PubMed:31555730). Acts by binding to the patched receptor (PTCH1 or PTCH2), relieving smoothened (SMO) inhibition by patched, activating the smoothened signaling pathway and transcription of target genes (PubMed:10753901, PubMed:29995851, PubMed:31548691, PubMed:31555730). In the absence of SHH, patched represses the constitutive signaling activity of SMO (PubMed:10753901). ShhN is widely expressed and plays a key role in the patterning of the central nervous system and limb development (By similarity). Induces ventral cell fate in the neural tube and somites (By similarity). Involved in the patterning of the anterior-posterior axis of the developing limb bud (By similarity). Essential for axon guidance (By similarity). {ECO:0000250|UniProtKB:Q62226, ECO:0000269|PubMed:10753901, ECO:0000269|PubMed:29995851, ECO:0000269|PubMed:30139912, ECO:0000269|PubMed:31127104, ECO:0000269|PubMed:31548691, ECO:0000269|PubMed:31555730, ECO:0000303|PubMed:24522195, ECO:0000303|PubMed:24863049}.