Figure 1
mtDNA mutational analysis in primary melanocytes and melanoma cell lines. (A) Circos plot of the mtDNA. External dots represent all the 86 mutation events in corresponding genes, and inner circular plots represent the average coverage of the sequencing for each cell line in the following order (from inside): FM308, WM35, WM1552, WM1789, WM278, WM793, WM902, 1205Lu, WM1617 and WM9; (B) There was no difference in the mtDNA mutation load among the melanoma stages (p = 0.6969, Kruskal-Wallis test); (C) Total number of mtDNA mutations per cell line. Note that mutation rates varied independently of the melanoma stage; (D) Unsupervised hierarquical clustarization analysis using the frequency of mutations in protein-coding genes. The clustarization was able to distinguish two mutated cell lines clusters (color bar at the bottom). Red color bar shows the cell line cluster with few mutations and the orange color bar the mtDNA highly mutated cluster. ND6 row is blank because the ND6 gene was hit by only one synonymous mutations in all cell lines, therefore there was not variation among the cell lines (Supplementary Table S1). Note in C, that genetically paired cell lines (WM793/1205Lu and WM278/WM1617) consistently showed equal number of mutations between the members of each pair. RGP: Radial Growth Phase; VGP: Vertical Growth Phase; MET: Metastatic Melanoma.
