Abstract
The mouse represents a key model system for the study of the physiology and biochemistry of skin. Comparison of skin between mouse and human is critical for interpretation and application of data from mouse experiments to human disease. Here, we review the current knowledge on structure and immunology of mouse and human skin. Moreover, we present a systematic comparison of human and mouse skin transcriptomes. To this end, we have recently used a genome-wide database of human gene expression to identify genes highly expressed in skin, with no, or limited expression elsewhere – human skin-associated genes (hSAGs). Analysis of our set of hSAGs allowed us to generate a comprehensive molecular characterization of healthy human skin. Here, we used a similar database to generate a list of mouse skin-associated genes (mSAGs). A comparative analysis between the top human (n=666) and mouse (n=873) skin-associated genes (SAGs) revealed a total of only 30.2% identity between the two lists. The majority of shared genes encode proteins that participate in structural and barrier functions. Analysis of the top functional annotation terms revealed an overlap for morphogenesis, cell adhesion, structure, and signal transduction. The results of this analysis, discussed in the context of published data, illustrate the diversity between the molecular make up of skin of both species and grants a probable explanation, why results generated in murine in vivo models often fail to translate into the human.
About the authors
Peter Arne Gerber is senior-consultant and scientific group leader in the Department of Dermatology at the University of Düsseldorf, Germany. He received his MD from the University of Düsseldorf and performed post-doctoral work in the Department of Physiology & Biophysics at the University of California, Irvine, USA. His current research interests include the identification and functional analysis of novel skin-specific genes and the molecular and cellular mechanisms of cutaneous adverse effects of targeted cancer drugs.
Peter Hevezi obtained his PhD in Microbiology from Columbia University, New York, and completed his post-doctoral work in Michael Bishop’s laboratory at The University of California, San Francisco. He is currently a Project Scientist at The University of California, Irvine. He has worked extensively in the biotechnology sector, most recently as Associate Director of Bioinformatics at Senomix, Inc (San Diego, California). His main interests are the identification and validation of biomarkers for human disease using gene expression analysis, bioinformatics and assay development. He has generated several extensive genome-wide databases of gene expression representing normal human tissues and cells and also primate taste buds.
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