Inspecting the secretory pathway with whole-cell, volumetric FIB-SEM

Date

Sep 20, 2021

Time

4:00 PM - 5:00 PM

Speaker

Jennifer Lippincott-Schwartz

Affiliation

Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, USA

Language

en

Main Topic

Biologie

Host

Rita Mateus

Description

Inside of a cell, snaking membranes comprising the ER synthesize up to 30% of the proteins encoded for by the genome. Many of these newly minted proteins only function after being exported from the ER to other cellular destinations. This occurs at sites distributed across the ER called ER exit sites (ERESs). Here, we provide a fresh look at ERESs and the secretory pathway using different imaging technologies, including whole-cell volumetric FIB-SEM. Rather than vesicles alone, the ER spawns an elaborate, interwoven tubular network of contiguous lipid bilayers (ER exit site) for protein export. This receptacle is capable of extending microns along microtubules while still connected to the ER by a thin neck. COPII localizes to this neck region and dynamically regulates cargo entry from the ER, while COPI acts more distally, escorting the detached, accelerating tubular entity on its way to joining the Golgi apparatus through microtubule-directed movement.

Last modified: Sep 21, 2021, 12:06:45 AM