AUTHOR=James Declan J., Martin Thomas F. TITLE=CAPS and Munc13: CATCHRs that SNARE Vesicles JOURNAL=Frontiers in Endocrinology VOLUME=Volume 4 - 2013 YEAR=2013 URL=https://www.frontiersin.org/journals/endocrinology/articles/10.3389/fendo.2013.00187 DOI=10.3389/fendo.2013.00187 ISSN=1664-2392 ABSTRACT=Abstract. CAPS (Calcium-dependent Activator Protein for Secretion, aka CADPS) and Munc13 (Mammalian Unc-13) proteins function to prime vesicles for Ca2+-triggered exocytosis in neurons and neuroendocrine cells. CAPS and Munc13 proteins contain conserved C-terminal domains that promote the assembly of SNARE complexes for vesicle priming. Similarities of the C-terminal domains of CAPS/Munc13 proteins with CATCHR (Complex Associated with Tethering Containing Helical Rods) domains in multi-subunit tethering complexes have been reported. Multi-subunit tethering complexes coordinate multiple interactions for SNARE complex assembly at constitutive membrane fusion steps. We review aspects of these diverse tethering and priming factors to identify common operating principles.