Fig. 3.

Laminin-332 induces dendricity in primary mouse melanocytes. (A) Phase-contrast micrographs of melanocytes cultured 24 h in the absence of exogenous extracellular matrix substrates (No ECM), on collagen I (Col I; 15 µg/cm²) or laminin-332 substrate (Lam 332). Scale bar: 64 µm. (B) The fraction of melanocytes exhibiting a ‘Spread’, ‘Bipolar’ or ‘Dendritic’ morphology was assessed on cultures seeded without exogenous extracellular matrix, on collagen I or on laminin-332. Each experiment was conducted in duplicate samples, and at least 50 cells per sample were scored. The results are expressed as the mean+s.d. (n=3 independent cell isolates). *P<0.05 (one-way ANOVA). Scale bar: 25 µm. (C) Distribution of dendrite abundance in melanocytes seeded on the indicated substrates. Melanocytes without dendrites (herewith defined as processes ≥13 µm) have been excluded. Red lines indicate the mean number of dendrites/cell on each substrate, irrespective of whether or not dendrites exhibited branches. Branches on dendrites were not counted. *P<0.05 (n=150 cells from 3 independent isolates; one-way ANOVA).