Is sonic hedgehog a gene or a protein or both?

Question

Is sonic hedgehog a gene or a protein or both?

I think sonic hedgehog is okay as a name for a chemical.

Having said that, I am a little bit concerned about the way sonic hedgehog seems to mean the protein and the gene that codes for it, which is likely to cause confusion.

"Sonic hedgehog is a protein encoded for by the SHH gene." says en.wikipedia.org/wiki/… which later says: "Two of these genes—i.e., desert hedgehog and Indian hedgehog—were named for species of hedgehogs, while sonic hedgehog was named after Sonic the Hedgehog, the protagonist character of the eponymous video game franchise. The gene was named as such by Robert Riddle, who was a postdoctoral fellow at the Tabin Lab, after his wife Betsy Wilder came home with a gaming magazine containing an advert for the Sonic the Hedgehog video game"

The New York Times: "A Gene Named Sonic". The New York Times. 1994-01-11.

Answer 1

Your confusion is warranted! The formatting rules for gene and protein nomenclature differ between model organisms. Even within a species, naming conventions may be inconsistently applied across the literature.

In Homo sapiens, the sonic hedgehog gene SHH (note italicization) encodes the sonic hedgehog protein SHH (or Shh protein, as on Uniprot). Human gene nomenclature is standardized by the HGNC.

As in humans, Drosophila gene and protein names are distinguished by different italicization; per FlyBase:

Protein product names and symbols should not be italicized in printed text. Where feasible, proteins that are named for the gene should be further distinguished by capitalizing the initial letter of the gene symbol or name. For example, the protein product(s) of the hh (hedgehog) gene could be correctly denoted as Hh or Hedgehog; the protein product(s) of the RpL38 (Ribosomal protein L38) gene could be correctly denoted as RpL38 or Ribosomal protein L38; and the the protein product(s) of the AGO1 (Argonaute-1) gene could be correctly denoted as AGO1 or Argonaute-1.

I’m partial to the naming conventions in Saccharomyces, where gene encodes PROTEIN (e.g. mpk1 and MPK1).

For both eukaryotic and prokaryotic microorganisms, the ASM Molecular and Cellular Biology submission guide for authors is a good resource for genetic nomenclature conventions.