Endoplasmic reticulum export machinery (COPII)

The Endoplasmic Reticulum (ER) export machinery is a multi-protein system, primarily centered around the Coat Protein Complex II (COPII), that facilitates the transport of proteins and lipids from the ER to the Golgi apparatus (Barlowe & Miller, 2013). This machinery operates at specialized ER exit sites (ERES) and involves a cycle of Sar1 GTPase activation, followed by the recruitment of the Sec23/24 inner coat and the Sec13/31 outer coat to form transport vesicles (UniProt Consortium, 2023). It is essential for cellular proteostasis and the biogenesis of the secretory pathway. Mutations in components like SEC23A or SAR1B lead to severe genetic disorders such as cranio-lenticulo-sutural dysplasia and chylomicron retention disease, respectively (Venditti et al., 2014). Furthermore, the machinery is often upregulated in cancers to support increased secretory demands and is hijacked by various viruses for replication (Kramer et al., 2013). While its essential nature poses challenges for drug development, small molecules like FLI-06 and Brefeldin A are used to experimentally inhibit these processes, highlighting the pathway's potential as a therapeutic target in specific contexts (Kramer et al., 2013).

Other names

COPII vesicle transport systemER-to-Golgi transport machineryEarly secretory pathway componentsER exit sitesERES

Inhibition of COPII vesicle formation, disruption of Sar1 GTPase cycle, or interference with cargo recruitment to ER exit sites.