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

Ahimou F, Mok LP, Bardot B, Wesley C - J. Cell Biol. (2004)

Bottom Line: Notch signaling is repeatedly used during animal development to specify cell fates.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.

View Article: PubMed Central - PubMed

Affiliation: Department of Microbiology and Molecular Genetics, The University of Vermont, VT 05405, USA.

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.

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Surface scans of cells expressing the different Notch receptors or Dl. (A) High-resolution AFM height images (100 × 100 nm; z range, 7 nm) of the surfaces of live heat-shocked S2 cell or S2 cells expressing the different proteins, scanned in 1× PBS+Ca2+. (B) Similar images of the surfaces of live S2 cells expressing Dl or N through the actin promoter. (C) Deflection images (z range, 16 nm) of the surface of an in situ “heat-shocked” S2-N cell. Higher resolution height images (100 × 100 nm; z range, 10 nm) on the right.
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fig4: Surface scans of cells expressing the different Notch receptors or Dl. (A) High-resolution AFM height images (100 × 100 nm; z range, 7 nm) of the surfaces of live heat-shocked S2 cell or S2 cells expressing the different proteins, scanned in 1× PBS+Ca2+. (B) Similar images of the surfaces of live S2 cells expressing Dl or N through the actin promoter. (C) Deflection images (z range, 16 nm) of the surface of an in situ “heat-shocked” S2-N cell. Higher resolution height images (100 × 100 nm; z range, 10 nm) on the right.

Mentions: To get some idea regarding the physical basis for the adhesion strength between N- and Dl-expressing cells, we scanned the surfaces of S2-N, S2-Dl, S2-N1-2155, S2-Nnd3, S2-NAx59d, S2-NΔ1-18, and S2-N (Ofut1−) cells, and many others using the pyramidal silicon nitride cantilever. Although the surface of heat-shocked untransfected S2 cells appeared plain and devoid of features, the surfaces of S2 cells expressing the different heat shock–induced cell surface molecules showed characteristic topologies (Fig. 4 A). For the following reasons, we consider these topologies to be related to the expression of cell surface proteins induced in the cells: (1) they are not an unrelated consequence of heat shock because heat-shocked S2 cells did not show these topologies; (2) the characteristic topology of each cell line was highly reproducible and other cell surface receptors like Dfrizzled 2 showed a different topology (unpublished data); (3) the topologies of the surfaces of S2 cells expressing N and Dl from the actin promoter were very similar to the topologies observed with S2-N and S2-Dl, respectively (Fig. 4 B); (4) when uninduced S2-N cells were placed in the AFM and the solution was heated in situ, the characteristic fibrous topology appeared in patches and spread to cover the whole surface (Fig. 4 C); (5) these characteristic topologies slowly reverted to the plain surface seen with S2 cells 2 d after the heat shock induction subsided (unpublished data); and (6) if the topologies are due to other proteins or molecules, it would raise the unlikely possibility that these were different for each Notch receptor, or responded differently to each Notch receptor.


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

Ahimou F, Mok LP, Bardot B, Wesley C - J. Cell Biol. (2004)

Surface scans of cells expressing the different Notch receptors or Dl. (A) High-resolution AFM height images (100 × 100 nm; z range, 7 nm) of the surfaces of live heat-shocked S2 cell or S2 cells expressing the different proteins, scanned in 1× PBS+Ca2+. (B) Similar images of the surfaces of live S2 cells expressing Dl or N through the actin promoter. (C) Deflection images (z range, 16 nm) of the surface of an in situ “heat-shocked” S2-N cell. Higher resolution height images (100 × 100 nm; z range, 10 nm) on the right.
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Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2172611&req=5

fig4: Surface scans of cells expressing the different Notch receptors or Dl. (A) High-resolution AFM height images (100 × 100 nm; z range, 7 nm) of the surfaces of live heat-shocked S2 cell or S2 cells expressing the different proteins, scanned in 1× PBS+Ca2+. (B) Similar images of the surfaces of live S2 cells expressing Dl or N through the actin promoter. (C) Deflection images (z range, 16 nm) of the surface of an in situ “heat-shocked” S2-N cell. Higher resolution height images (100 × 100 nm; z range, 10 nm) on the right.
Mentions: To get some idea regarding the physical basis for the adhesion strength between N- and Dl-expressing cells, we scanned the surfaces of S2-N, S2-Dl, S2-N1-2155, S2-Nnd3, S2-NAx59d, S2-NΔ1-18, and S2-N (Ofut1−) cells, and many others using the pyramidal silicon nitride cantilever. Although the surface of heat-shocked untransfected S2 cells appeared plain and devoid of features, the surfaces of S2 cells expressing the different heat shock–induced cell surface molecules showed characteristic topologies (Fig. 4 A). For the following reasons, we consider these topologies to be related to the expression of cell surface proteins induced in the cells: (1) they are not an unrelated consequence of heat shock because heat-shocked S2 cells did not show these topologies; (2) the characteristic topology of each cell line was highly reproducible and other cell surface receptors like Dfrizzled 2 showed a different topology (unpublished data); (3) the topologies of the surfaces of S2 cells expressing N and Dl from the actin promoter were very similar to the topologies observed with S2-N and S2-Dl, respectively (Fig. 4 B); (4) when uninduced S2-N cells were placed in the AFM and the solution was heated in situ, the characteristic fibrous topology appeared in patches and spread to cover the whole surface (Fig. 4 C); (5) these characteristic topologies slowly reverted to the plain surface seen with S2 cells 2 d after the heat shock induction subsided (unpublished data); and (6) if the topologies are due to other proteins or molecules, it would raise the unlikely possibility that these were different for each Notch receptor, or responded differently to each Notch receptor.

Bottom Line: Notch signaling is repeatedly used during animal development to specify cell fates.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.

View Article: PubMed Central - PubMed

Affiliation: Department of Microbiology and Molecular Genetics, The University of Vermont, VT 05405, USA.

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.

Show MeSH
Related in: MedlinePlus