FIGURE 7.

Contribution of αLNNd to laminin accumulation on Schwann cell (SC) surfaces. Cells were cultured with the indicated proteins for 1 h and immunostained for the laminin β1 subunit (E4-specific antibody). Panels A and B, quantitation of laminin (A) and corresponding entactin antigen (B) immunofluorescence summed cell intensities for laminin (Lm, closed circles), αLNNd (constant 26 nm) with increasing LmΔαLN (closed inverted triangles), nidogen-1 (26 nm) with increasing LmΔαLN (open triangles), and LmΔαLN alone (open circles) (average and S.D., n ≥ 5). The addition of αLNNd, but not nidogen-1, to the non-polymerizing LmΔαLN enabled self-assembly to a degree approaching that of intact laminin. Panels C and D, cells were incubated with the indicated proteins (constant 14 nm laminin and 14 nm αLNNd). αLNNd enabled the cell surface assembly of laminins bearing deletions of the αLN domain but not deletions of the βLN or γLN domains.