Grond, RianneVeenendaal, TinekeDuran, Juan M.Raote, IshierVan Es, Johan H.Corstjens, SebastiaanDelfgou, LauraEl Haddouti, BenaissaMalhotra, VivekRabouille, Catherine2020-11-232020Grond R, Veenendaal T, Duran JM, Raote I, van Es JH, Corstjens S, Delfgou L, El Haddouti B, Malhotra V, Rabouille C. The function of GORASPs in Golgi apparatus organization in vivo. J Cell Biol. 2020; 219(9):e202004191. DOI: 10.1083/jcb.2020041910021-9525http://hdl.handle.net/10230/45832In vitro experiments have shown that GRASP65 (GORASP1) and GRASP55 (GORASP2) proteins function in stacking Golgi cisternae. However, in vivo depletion of GORASPs in metazoans has given equivocal results. We have generated a mouse lacking both GORASPs and find that Golgi cisternae remained stacked. However, the stacks are disconnected laterally from each other, and the cisternal cross-sectional diameters are significantly reduced compared with their normal counterparts. These data support earlier findings on the role of GORASPs in linking stacks, and we suggest that unlinking of stacks likely affects dynamic control of COPI budding and vesicle fusion at the rims. The net result is that cisternal cores remain stacked, but cisternal diameter is reduced by rim consumption.application/pdfeng© 2020 Grond et al. This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms/). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 International license, as described at https://creativecommons.org/licenses/by-nc-sa/4.0/).info:eu-repo/semantics/articlehttp://dx.doi.org/10.1083/jcb.202004191OrganellesTraffickinginfo:eu-repo/semantics/openAccess