Author Interviews, Endocrinology / 04.05.2018 Interview with: Marcus M. Seldin PhD (Post-doc researcher) and Professor Aldons J. Lusis, PhD Department of Medicine, Department of Human Genetics Department of Microbiology, Immunology and Molecular Genetics University of California, Los Angeles, CA, What is the background for this study? What are the main findings? Response: There are thousands of proteins which circulate in the blood and relay signals between tissues, however many of their functions remain difficult to dissect.  We used a mouse population, termed the Hybrid Mouse Diversity Panel (HMDP) to ask if we can identify new factors which communicate between tissues.  Taking this approach, we uncover several proteins which relay signals between tissues.  These include Lipocalin-5, an adipose-expressed protein which can promote skeletal muscle respiration and liver-derived Notum which enhances thermogenesis in fat tissue.  The approach we developed can also be broadly applied to many mouse and human datasets.  As proof of this, we show that cross-tissue predictions are remarkably conserved between mice and humans