On guard: coronin proteins in innate and adaptive immunity. 
Recent work has implicated members of the evolutionarily conserved family of coronin proteins - in particular coronin 1 - in immune homeostasis.  Coronins are involved in processes as diverse as pathogen survival in phagocytes and homeostatic T cell signalling.  Notably, in both mice and humans, coronin mutations are associated with immune deficiencies and resistance to autoimmunity.  In this article, we review what is currently known about these conserved molecules and discuss a potential common mechanism that underlies their diverse activities, which seem to involve cytoskeletal interactions as well as calcium-calcineurin signalling.