The adhesion force of Notch with Delta and the rate of Notch signaling

Abstract

Notch signaling is repeatedly used during animal development to specify cell fates. Using atomic force microscopy on live cells, chemical inhibitors, and conventional analyses, we show that the rate of Notch signaling is linked to the adhesion force between cells expressing Notch receptors and Delta ligand. Both the Notch extracellular and intracellular domains are required for the high adhesion force with Delta. This high adhesion force is lost within minutes, primarily due to the action of Presenilin on Notch. Reduced turnover or Delta pulling accelerate this loss. These data suggest that strong adhesion between Notch and Delta might serve as a booster for initiating Notch signaling at a high rate.

Leukemia-Associated Mutations within the NOTCH1 Heterodimerization Domain Fall into at Least Two Distinct Mechanistic Classes

“…One interesting possibility is that a similar displacement of the LNR/HD negative regulatory unit might result from a mechanical force that is transmitted along the long axis of the receptor in response to ligand binding and endocytosis. If so, such forces could promote S2 cleavage prior to physical removal of the N EC subunit, a possibility that is in line with several studies from the fly (1,18 (34), thus expanding an ectopic pool of cells that are at risk for acquisition of additional genetic events and eventual outgrowth as T-ALL. In support of this scenario, patients with T-ALL do not always have thymic involvement at the time of diagnosis (suggesting that these tumors sometimes originate within the bone marrow), and the thymus is expendable for FIG.…”

“…Models involving receptor oligomerization have been proposed, but recent data suggest that both metalloprotease-sensitive and -resistant forms of NOTCH receptors exist primarily as monomers (46). An alternative mechanism supposes that NOTCH1 is rendered sensitive to S2 cleavage by a change in conformation (46), which could occur in response to mechanical forces generated by the endocytic machinery of the ligand-expressing cell (1,22,30,43).…”

Force measurements with the atomic force microscope: Technique, interpretation and applications

“…Due to the experimental difficulties involved, examples of such measurements are still rare [991][992][993]. These studies demonstrate the potential of the cell probe technique to directly access information on cell-cell interaction under physiological conditions.…”

Regulation of Notch signaling by glycosylation

“…Even so, such assays may not appropriately reflect in vivo interactions between Notch and ligands which occur in specialized, dynamic, plasma membrane compartments of apposing cells. In this regard, atomic force microscopy may provide the most physiologically relevant data [17].…”