Genome-wide Transcriptome Analysis of Human Edpidermal Melanocyctes

Because human epidermal melanocytes (HEMs) provide critical protection against skin cancer,
sunburn, and photoaging, a genome-wide perspective of gene expression in these cells is
critical to understanding human skin physiology. In this study we performed high throughput
sequencing of HEMs to obtain a complete data set of transcript sizes, abundances, and splicing.
As expected, we found that melanocyte specific genes that function in pigmentation were
among the highest expressed genes. We analyzed the receptor, ion channel and transcription
factor gene families to get a better understanding of the cell signalling pathways used by
melanocytes. We also performed a comparative transcriptomic analysis of lightly versus
darkly pigmented HEMs and found 16 genes differentially expressed in the two pigmentation
phenotypes; of those, only one putative melanosomal transporter (SLC45A2) has known
function in pigmentation. Our melanocyte transcriptome study provides a comprehensive view
and may help identify novel pigmentation genes and potential pharmacological targets.