ER arrival sites associate with ER exit sites to create bidirectional transport portals

Chowdhury, Sudeshna Roy; Bhattacharjee, Chumki; Casler, Jason C.; Jain, Bhawik Kumar; Glick, Benjamin S.; Bhattacharyya, Dibyendu

doi:10.1083/jcb.201902114

Cited by 21 publications

(29 citation statements)

References 64 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is possible that the need for long-range tethering is obviated by the close association of ER export and arrival sites. In the yeast Pichia pastoris, this creates bidirectional transport portals at which the Dsl1 complex may be able to capture COPI vesicles as they are budding from the Golgi (49).…”

Section: Discussionmentioning

confidence: 99%

Structural basis for the binding of SNAREs to the multisubunit tethering complex Dsl1

Travis

DAmico

et al. 2020

Journal of Biological Chemistry

View full text Add to dashboard Cite

Multisubunit tethering complexes (MTCs) are large (250 to >750 kDa), conserved macromolecular machines that are essential for SNARE-mediated membrane fusion in all eukaryotes. MTCs are thought to organize membrane trafficking by mediating the initial, long-range interaction between a vesicle and its target membrane and promoting the formation of membrane-bridging SNARE complexes. Previously, we reported the structure of the yeast Dsl1 complex, the simplest known MTC, which is essential for COPI-mediated transport from the Golgi to the endoplasmic reticulum (ER). This structure suggests how the Dsl1 complex might tether a vesicle to its target membrane by binding at one end to the COPI coat and at the other to ER-associated SNAREs. Here, we used X-ray crystallography to investigate these Dsl1–SNARE interactions in greater detail. The Dsl1 complex comprises three subunits that together form a two-legged structure with a central hinge. We found that distal regions of each leg bind N-terminal Habc domains of the ER SNAREs Sec20 (a Qb-SNARE) and Use1 (a Qc-SNARE). The observed binding modes appear to anchor the Dsl1 complex to the ER target membrane while simultaneously ensuring that both SNAREs are in open conformations, with their SNARE motifs available for assembly. The proximity of the two SNARE motifs, and therefore their ability to enter the same SNARE complex, will depend on the relative orientation of the two Dsl1 legs. These results underscore the critical roles of SNARE N-terminal domains in mediating interactions with other elements of the vesicle-docking and -fusion machinery.

show abstract

Section: Discussionmentioning

confidence: 99%

Structural basis for the binding of SNAREs to the multisubunit tethering complex Dsl1

Travis

DAmico

et al. 2020

Journal of Biological Chemistry

View full text Add to dashboard Cite

show abstract

“…The question as to where COPI vesicles fuse on the ER has been addressed by expressing (X)FP‐tagged proteins homologous to those belonging to the COPI‐tethering factor complex of mammals. This strategy has been successfully applied to both plants (Lerich et al ., 2012), and more recently in Pichia pastoris (a yeast with a stacked Golgi) (Chowdhury et al ., 2020), and reveals that ERIS lie close to ERES on the ER membrane, that is, immediately underneath the cis ‐cisterna. This indicates that bidirectional transport is restricted to the ER–Golgi interface, and is in accord with the Secretory Unit concept.…”

Section: Er Exit Sites (Eres) Er Import Sites (Eris) and The Assemblmentioning

confidence: 99%

Plant Golgi ultrastructure

Robinson

2020

Journal of Microscopy

View full text Add to dashboard Cite

The plant Golgi apparatus (sensu lato: Golgi stack + Trans Golgi Network, TGN) is a highly polar and mobile key organelle lying at the junction of the secretory and endocytic pathways. Unlike its counterpart in animal cells it does not disassemble during mitosis. It modifies glycoproteins sent to it from the endoplasmic reticulum (ER), it recycles ER resident proteins, it sorts proteins destined for the vacuole from secretory proteins, it receives proteins internalised from the plasma membrane and either recycles them to the plasma membrane or retargets them to the vacuole for degradation. In functional terms the Golgi apparatus can be likened to a car factory, with incoming (COPII traffic) and returning (COPI traffic) railway lines at the entry gate, and a distribution centre (the TGN) at the exit gate of the assembly hall. In the assembly hall we have a conveyor belt system where the incoming car parts are initially assembled (in the cis-area) then gradually modified into different models (processing of secretory cargo) as the cars pass along the production line (cisternal maturation). After being released the trans-area, the cars (secretory cargos) are moved out of the assembly hall and passed on to the distribution centre (TGN), where the various models are placed onto different trains (cargo sorting into carrier vesicles) for transport to the car dealers. Cars with motor problems are returned to the factory for repairs (endocytosis to the TGN). This simple analogy also incorporates features of quality control at the COPII entry gate with defective parts being returned to the manufacturing center (the ER) via the COPI trains (vesicles). In recent years, numerous studies have contributed to our knowledge on Golgi function and structure in both animals, yeast and plants. This review, rather than giving a balanced account of the structure as well as of the function of the Golgi apparatus has purposely a marked slant towards plant Golgi ultrastructure integrating findings from the mammalian/animal field.

show abstract

“…COPI and COPII coat proteins appear to concentrate in peripheral and central positions of the ERES cup, respectively. To confirm this complementary distribution, reminiscent of recent findings in the yeast Pichia pastoris (Roy Chowdhury et al, 2020), we examined ERES-Golgi units in fat body expressing Sec13.GFP and γCOP.RFP simultaneously. This confirmed that COPII is found at the center of ERES, whereas COPI occupies preferentially the periphery of the structure (Figure 4A).…”

Section: Resultsmentioning

confidence: 55%

“…Among these, budding of Golgi-bound membrane carriers at ERES is known to involve the COPII coat complex, a set of proteins highly conserved in eukaryotes (Jensen and Schekman, 2011). In these same ERES regions, in addition, traffic in the reverse Golgi-ER direction through COPI vesicles is thought to concentrate as well (Roy Chowdhury et al, 2020). Despite their highly dynamic underlying nature, live imaging has repeatedly shown that ERES are relatively long-lived, stable entities (daSilva et al, 2004; Hammond and Glick, 2000; Shindiapina and Barlowe, 2010; Westrate et al, 2020).…”

Section: Introductionmentioning

confidence: 99%

ER exit sites inDrosophiladisplay abundant ER-Golgi vesicles and pearled tubes but no megacarriers

Yang

Liu

Feng

et al. 2021

Preprint

View full text Add to dashboard Cite

Secretory cargos are collected at ER exit sites (ERES) before transport to the Golgi apparatus. Decades of research have provided many details of the molecular events underlying ER-Golgi exchanges. Essential questions, however, remain about the organization of the ER-Golgi interface in cells and the type of membrane structures mediating traffic from ERES. To investigate these, we used transgenic tagging in Drosophila flies, 3D-SIM and FIB-SEM to characterize ERES-Golgi units in collagen-producing fat body, imaginal discs and imaginal discs overexpressing ERES determinant Tango1. We found in front of ERES a pre-cis-Golgi region involved in both anterograde and retrograde transport. This pre-cis-Golgi is continuous with the rest of the Golgi, not a separate intermediate compartment or collection of large carriers, for which we found no evidence. We found, however, many vesicles, as well as pearled tubules connecting ERES and Golgi.

show abstract

ER arrival sites associate with ER exit sites to create bidirectional transport portals

Cited by 21 publications

References 64 publications

Structural basis for the binding of SNAREs to the multisubunit tethering complex Dsl1

Structural basis for the binding of SNAREs to the multisubunit tethering complex Dsl1

Plant Golgi ultrastructure

ER exit sites inDrosophiladisplay abundant ER-Golgi vesicles and pearled tubes but no megacarriers

Contact Info

Product

Resources

About