Molecular cell types as functional units of the efferent vagus nerve Author: Tatiana C Coverdell1, Stephen B G Abbott2, John N Campbell3 Affiliation: <sup>1</sup> Biomedical Sciences Graduate Program, University of Virginia, Charlottesville, VA 22903, USA. <sup>2</sup> Department of Pharmacology, University of Virginia, Charlottesville, VA 22903, USA. <sup>3</sup> Department of Biology, University of Virginia, Charlottesville, VA 22903, USA. Electronic address: jnc4e@virginia.edu. Conference/Journal: Semin Cell Dev Biol Date published: 2023 Jul 26 Other: Special Notes: doi: 10.1016/j.semcdb.2023.07.007. , Word Count: 140 The vagus nerve vitally connects the brain and body to coordinate digestive, cardiorespiratory, and immune functions. Its efferent neurons, which project their axons from the brainstem to the viscera, are thought to comprise "functional units" - neuron populations dedicated to the control of specific vagal reflexes or organ functions. Previous research indicates that these functional units differ from one another anatomically, neurochemically, and physiologically but have yet to define their identity in an experimentally tractable way. However, recent work with genetic technology and single-cell genomics suggests that genetically distinct subtypes of neurons may be the functional units of the efferent vagus. Here we review how these approaches are revealing the organizational principles of the efferent vagus in unprecedented detail. Keywords: Dorsal motor nucleus of the vagus; Nucleus ambiguus; Parasympathetic preganglionic; Tenth cranial nerve; Vagal motor neuron. PMID: 37507330 DOI: 10.1016/j.semcdb.2023.07.007