FRAGMENT FROM NATURE this weekend is a historical vignette on the discovery of nuclear receptors in cells, based on a lovely 2014 review by Ronald Evans and David Mangelsdorf. The gene isolation of nuclear receptors led to the discovery of receptors without known function, so-called “orphan receptors” which eventually were assigned to functional pathways. Importantly, these orphan receptors belonged to large conserved superfamilies. This was effectively the start of molecular endocrinology, a far-reaching discipline that had a big impact on medicine.