What is Sonic hedgehog?
[[File:Shh structure.png|right|250px|Overview of molecular structure]] {{For|the video game character after which the protein is named|Sonic the Hedgehog (character)}} The '''sonic hedgehog protein''' '''(SHH)''' is coded by the ''SHH'' [[gene]].<ref>{{cite journal | vauthors = Marigo V, Roberts DJ, Lee SM, Tsukurov O, Levi T, Gastier JM, Epstein DJ, Gilbert DJ, Copeland NG, Seidman CE | display-authors = 6 | title = Cloning, expression, and chromosomal location of SHH and IHH: two human homologues of the ''Drosophila'' segment polarity gene hedgehog | journal = Genomics | volume = 28 | issue = 1 | pages = 44–51 | date = July 1995 | pmid = 7590746 | doi = 10.1006/geno.1995.1104 }}</ref> The protein is named after the character ''[[Sonic the Hedgehog (character)|Sonic the Hedgehog]]''. This key signalling molecule ''regulates embryonic development in all animals''. SHH controls organogenesis and the organization of the central nervous system, limbs, digits and many other parts of the body. Sonic hedgehog is a [[Morphogenesis|morphogen]] that patterns the developing embryo using a concentration gradient.<ref>{{cite journal | vauthors = Jaeger J, Martinez-Arias A | title = Getting the measure of positional information | journal = PLOS Biology | volume = 7 | issue = 3 | pages = e81 | date = March 2009 | pmid = 19338391 | pmc = 2661971 | doi = 10.1371/journal.pbio.1000081 }}</ref> Abnormal activation of SHH signalling in adult tissues causes various types of [[cancer]]s. General readers might look for a simplified account by an expert author.<ref> Carey, Nessa 2017. ''Junk DNA: a journey through the dark matter of the genome''. Columbia University Press. ISBN 9780231539418, p202.</ref> == References == {{reflist}} [[Category:Developmental biology]] [[Category:Proteins]]