Scabrous as a Positive Regulator of the Cis ‐Inhibition of Notch

ABSTRACT

Notch receptors play numerous roles during development and throughout adult life, and the regulation of Notch signaling life has been studied in detail during normal development and in disease contexts. Scabrous is a large extracellular protein interacting with Notch that was identified genetically as a positive regulator of Notch signaling in Drosophila . Scabrous is a secreted protein that is usually thought to diffuse away from its source to interact with the extracellular domain of Notch and thereby promotes receptor activation in distant cells. However, how Scabrous regulates Notch activity has remained unclear. Here, I will re‐examine the published findings about the role of Scabrous and hypothesize that Scabrous acts in endosomes to regulate the cis‐inhibition of Notch.