InterPro

Imaginal disc growth factors (IDGFs), also known as chitinase-like proteins, are soluble factors involved in the regulation of proliferation in imaginal discs [PMID: 11444043]. They are a family of growth factors identified in insects that include at least five members, some of which are encoded by genes in a tight cluster [PMID: 12242232]. The IDGFs have an eight-stranded alpha/beta barrel fold and are related to the glycosyl hydrolase family 18 (GH18) chitinases, but they have an amino acid substitution known to abolish chitinase catalytic activity [PMID: 17594485]. IDGFs may have evolved from chitinases to gain new functions as growth factors, interacting with cell surface glycoproteins involved in growth-promoting processes [PMID: 11821393].