Argos is a secreted protein that is an inhibitor of the epidermal growth factor receptor (EGFR) pathway in Drosophila melanogaster.
[3] Argos represents the first example of ligand sequestration as a mechanism of inhibition in the ErbB (EGFR) family.
[1] The name of the gene derives from the phenotype of mutant flies with eye defects and refers to Argus Panoptes.
Crystallographic studies have revealed that Argos does not contain an EGF domain as originally expected.
The Argos domain has features in common with the three finger toxin fold that is found in a number of proteins including TGF beta receptors and the urokinase (uPA) receptor.