Meeting report – Emerging Concepts in Cell Organization

Abstract

New concepts in cell organization emerged in a medieval castle during a snowy week in January 2017 in the middle of the Austrian Alps. The occasion was the 10th Annaberg EMBO workshop in Goldegg am See; organized by Gabriele Seethaler, Catherine Rabouille and Marino Zerial. There were 95 participants, including many who gave talks and presented posters, enjoying a familial and trusting atmosphere that stimulated lively exchange of (unpublished) results, new ideas and thoughts.As at previous occasions when this community met in the same spot, the aim of the meeting was to identify the key questions in cell biology and set the ground for future research directions. The inspirational character of the meeting and the enthusiasm of the participants certainly achieved that. The new concepts that emerged will be shaping our understanding of how cells are organized and how this organization impacts cellular functions. Overall, it became clear that there is a discrepancy between the textbook views of the cellular building plan and how the field currently envisions a cell is really built. Furthermore, novel methods allow the study of the complexity of cellular organization, and old methods are being revisited. This report is an attempt to recapitulate and integrate the ideas that emerged at the workshop, and thereby provide inspiration to the larger community. All presentations and, in particular the lively poster sessions, were essential for the success of the meeting. However, owing to space restrictions, we could not cover all short talks or the posters here. We apologize to our colleagues whose presentations could not be discussed here.Secretion: making proteins and membranes and how to get them out A lot remains to be discovered about intra-organelle communication by 'classical' vesicular trafficking, especially in the secretory pathway. For instance, how do cells ensure that vesicles contain the right cargo? Liz Miller (MRC LMB, Cambridge, UK) explained protein quality control at endoplasmic reticulum (ER) exit sites and presented a cargo-crowding mechanism that helps to exclude ER-resident proteins from being packed into COPII vesicles, thereby preventing their 'spilling over' into the Golgi.While ER export has been intensely studied, exit sites from the trans-Golgi network (TGN) have remained more elusive. Stéphanie Miserey-Lenkei (Institut Curie, Paris, France) highlighted that RAB6 controls membrane fission of transport vesicles at the TGN through coupling motor proteins of the kinesin and myosin family to the cytoskeleton at specific sites of fission. This coupling ensures the spatial coordination between the fission of RAB6-positive vesicles and their exit along microtubules (Miserey-Lenkei et al., under review).Another important question is how is specificity in trafficking to and through the Golgi achieved? After all, the Golgi is the major protein distribution center of the cell. Sean Munro (MRC LMB, Cambridge, UK), this year's winner of the famous Grunzelsbacher award (sponsored by the elusive Aus...