Abstract
David John “Davo” Mangelsdorf passed away on August 3, 2025, in Dallas, Texas at age 67 from an unexpected postsurgical complication. Davo made transformative contributions to nuclear receptor and metabolic biology. He discovered the retinoid X receptor (RXR) during his early years at Salk and, during his career and leadership at UT Southwestern, helped define the roles of orphan nuclear receptors, including LXR and FXR, as well as the metabolic hormones FGF19 and FGF21. This retrospective also reflects on the person behind the science. Davo brought curiosity, humor, and a sense of ease to every interaction. His legacy endures in his discoveries, in the colleagues and trainees he inspired, and in the kindness and laughter he shared throughout his life.