Faculty Opinions recommendation of Reconstitution of COPII vesicle fusion to generate a pre-Golgi intermediate compartment.

AbstractComplex machinery is required to drive secretory cargo export from the endoplasmic reticulum. In vertebrates, this includes transport and Golgi organization protein 1 (TANGO1), encoded by the Mia3 gene. Here, using genome engineering of human cells light microscopy, secretion assays, and proteomics, we show loss of Mia3/TANGO1 results in formation of numerous vesicles and a loss of early secretory pathway integrity. This restricts secretion not only of large proteins like procollagens but of all types of secretory cargo. Our data shows that Mia3/TANGO1 constrains the propensity of COPII to form vesicles promoting instead the formation of the ER-Golgi intermediate compartment. Thus, Mia3/TANGO1 facilities the secretion of complex and high volume cargoes from vertebrate cells.

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SNARE Status Regulates Tether Recruitment and Function in Homotypic COPII Vesicle Fusion

Journal of Biological Chemistry ◽

10.1074/jbc.m606044200 ◽

2006 ◽

Vol 281 (50) ◽

pp. 38825-38833 ◽

Cited By ~ 39

Author(s):

Marvin Bentley ◽

Yingjian Liang ◽

Karl Mullen ◽

Dalu Xu ◽

Elizabeth Sztul ◽

...

Keyword(s):

Vesicle Fusion ◽

Copii Vesicle ◽

And Function

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Poliovirus Infection Transiently Increases COPII Vesicle Budding

Journal of Virology ◽

10.1128/jvi.01159-12 ◽

2012 ◽

Vol 86 (18) ◽

pp. 9675-9682 ◽

Cited By ~ 19

Author(s):

Meg Trahey ◽

Hyung Suk Oh ◽

Craig E. Cameron ◽

Jesse C. Hay

Keyword(s):

Golgi Apparatus ◽

Secretory Pathway ◽

Vesicle Formation ◽

Vesicle Budding ◽

Precursor Pool ◽

Copii Vesicle ◽

Early Increase ◽

Vesicle Biogenesis ◽

Intermediate Compartment ◽

Copii Vesicles

Poliovirus (PV) requires membranes of the host cell's secretory pathway to generate replication complexes (RCs) for viral RNA synthesis. Recent work identified the intermediate compartment and the Golgi apparatus as the precursors of the replication “organelles” of PV (N. Y. Hsu et al., Cell 141:799–811, 2010). In this study, we examined the effect of PV on COPII vesicles, the secretory cargo carriers that bud from the endoplasmic reticulum and homotypically fuse to form the intermediate compartment that matures into the Golgi apparatus. We found that infection by PV results in a biphasic change in functional COPII vesicle biogenesis in cells, with an early enhancement and subsequent inhibition. Concomitant with the early increase in COPII vesicle formation, we found an increase in the membrane fraction of Sec16A, a key regulator of COPII vesicle formation. We suggest that the early burst in COPII vesicle formation detected benefits PV by increasing the precursor pool required for the formation of its RCs.

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A new type of ERGIC-ERES membrane contact mediated by TMED9 and SEC12 is required for autophagosome biogenesis

10.1101/2021.05.19.444771 ◽

2021 ◽

Author(s):

Shulin Li ◽

Rui Yan ◽

Jialu Xu ◽

Shiqun Zhao ◽

Xinyu Ma ◽

...

Keyword(s):

Short Distance ◽

Protein Transport ◽

Secretory Protein ◽

Endomembrane System ◽

Exit Site ◽

Copii Vesicle ◽

Golgi System ◽

New Type ◽

Membrane Contact ◽

Intermediate Compartment

Under stress, the endomembrane system undergoes reorganization to support autophagosome biogenesis, which is a central step in autophagy. How the endomembrane system remodels has been poorly understood. Here we identify a new type of membrane contact formed between the ER-Golgi intermediate compartment (ERGIC) and the ER-exit site (ERES) in the ER-Golgi system, which is essential for promoting autophagosome biogenesis induced by different stress stimuli. The ERGIC-ERES contact is established by the interaction between TMED9 and SEC12 which generates a short distance opposition (as close as 2-5 nm) between the two compartments. The tight membrane contact allows the ERES-located SEC12 to transactivate COPII assembly on the ERGIC. In addition, a portion of SEC12 also relocates to the ERGIC. Through both mechanisms, the ERGIC-ERES contact promotes formation of the ERGIC-derived COPII vesicle, a membrane precursor of the autophagosome. The ERGIC-ERES contact is physically and functionally different from the TFG-mediated ERGIC-ERES adjunction involved in secretory protein transport, and therefore defines a unique endomembrane structure generated upon stress conditions for autophagic membrane formation.

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Reconstitution of COPII vesicle fusion to generate a pre-Golgi intermediate compartment

The Journal of Cell Biology ◽

10.1083/jcb.200408135 ◽

2004 ◽

Vol 167 (6) ◽

pp. 997-1003 ◽

Cited By ~ 67

Author(s):

Dalu Xu ◽

Jesse C. Hay

Keyword(s):

Endoplasmic Reticulum ◽

Membrane Fusion ◽

Secretory Pathway ◽

Golgi Stack ◽

Golgi Membranes ◽

Transport Vesicles ◽

Copii Vesicle ◽

Intermediate Compartment ◽

Copii Vesicles

What is the first membrane fusion step in the secretory pathway? In mammals, transport vesicles coated with coat complex (COP) II deliver secretory cargo to vesicular tubular clusters (VTCs) that ferry cargo from endoplasmic reticulum exit sites to the Golgi stack. However, the precise origin of VTCs and the membrane fusion step(s) involved have remained experimentally intractable. Here, we document in vitro direct tethering and SNARE-dependent fusion of endoplasmic reticulum–derived COPII transport vesicles to form larger cargo containers. The assembly did not require detectable Golgi membranes, preexisting VTCs, or COPI function. Therefore, COPII vesicles appear to contain all of the machinery to initiate VTC biogenesis via homotypic fusion. However, COPI function enhanced VTC assembly, and early VTCs acquired specific Golgi components by heterotypic fusion with Golgi-derived COPI vesicles.

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