Toll (gene)

The Toll genes encode members of the Toll-like receptor class of proteins. ("Toll" is German for "amazing" or "mad".) Toll genes were originally identified in the fruit fly Drosophila melanogaster in 1985, , and cloned in 1988. Since then, eleven known mammalian Toll genes have been identified.

In flies, Toll was first identified as a gene important in embryogenesis in establishing the dorsal-ventral axis. In 1996, Toll was found to have a role in the fly's immunity to fungal infections. Both mammalian and invertebrate Toll genes are required for innate immunity.

Toll-like receptors in mammals were identified in 1997 at Yale University by Ruslan Medzhitov and Charles Janeway.

Their name derives from Christiane Nüsslein-Volhard's 1985 exclamation, "Das war ja toll!"