explain proteolytic cleavage of Notch.
the first proteolytic processing step occurs within the trans Golgi network to generate the mature heterodimeric Notch receptor that is then displayed on the cell surface
The binding of Delta triggers the next two proteolytic steps: complex of Delta and the Notch subunit to which it is bound is endocytosed by the Delta-expressing cell, exposing the extracllular cleavage site in the transmembrane Notch subunit