Dermal fibroblast derived paracrine signaling regulates expression of genes involved in melanin biosynthesis.

<p>Baseline expression of 6 genes involved in melanogenesis varied significantly between the melanocyte samples (<i>p</i><0.01 for all genes); conditioned medium significantly affected gene expression (<i>p</i><0.001 for all genes). The degree of response to conditioned medium was significantly different between melanocyte samples for MITF (<i>p</i><0.0001), TYR (<i>p</i><0.0001), TYRP1 (<i>p</i> = 0.02), and TYRP2 (<i>p<</i>0.0001) and was nearly significant for DKK1 (<i>p</i> = 0.07), but not for MC1R (<i>p</i> = 0.22). Statistical analysis was based on average values across all six melanocyte lineages rather than individual sample responses to fibroblast-conditioned medium (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0139135#sec006" target="_blank">Methods</a>).