Journal
JOURNAL OF CELL SCIENCE
Volume 122, Issue 16, Pages 2924-2934Publisher
COMPANY BIOLOGISTS LTD
DOI: 10.1242/jcs.044032
Keywords
COPII; Membrane traffic; Secretion; Vesicle formation
Categories
Funding
- Senior Non-Clinical Fellowship [G117/553]
- BBSRC [BB/E019633]
- doctoral training account studentships
- Biotechnology and Biological Sciences Research Council [BB/E019633/1] Funding Source: researchfish
- Medical Research Council [G117/554] Funding Source: researchfish
- BBSRC [BB/E019633/1] Funding Source: UKRI
- MRC [G117/554] Funding Source: UKRI
Ask authors/readers for more resources
The COPII complex mediates the selective incorporation of secretory cargo and relevant machinery into budding vesicles at specialised sites on the endoplasmic reticulum membrane called transitional ER (tER). Here, we show using confocal microscopy, immunogold labelling of ultrathin cryosections and electron tomography that in human cells at steady state, Sec16 localises to cup-like structures of tER that are spatially distinct from the localisation of other COPII coat components. We show that Sec16 defines the tER, whereas Sec23-Sec24 and Sec13-Sec31 define later structures that precede but are distinct from the intermediate compartment. Steady-state localisation of Sec16 is independent of the localisation of downstream COPII components Sec23-Sec24 and Sec13-Sec31. Sec16 cycles on and off the membrane at a slower rate than other COPII components with a greater immobile fraction. We define the region of Sec16A that dictates its robust localisation of tER membranes and find that this requires both a highly charged region as well as a central domain that shows high sequence identity between species. The central conserved domain of Sec16 binds to Sec13 linking tER membrane localisation with COPII vesicle formation. These data are consistent with a model where Sec16 acts as a platform for COPII assembly at ERES.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available