The structure of a COPII tubule

O’Donnell, Jason; Maddox, Kerry; Stagg, Scott M.

doi:10.1016/j.jsb.2010.09.002

Cited by 18 publications

(12 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This same study also revealed that the Sec23/24 cargo adaptor assembled into a regular lattice on the membrane surface [48] . Taken together, the findings from this and earlier work [43, 44, 49, 46, 47] indicate that the COPII coat can adopt a variety of geometries to accommodate a range of vesicle sizes, with the Sec23/24 adaptor itself playing an unexpected structural role in determining vesicle shape [48] .…”

Section: Copii Coat Assembly May Accommodate Different Cargo Sizessupporting

confidence: 58%

Cargo adaptors: structures illuminate mechanisms regulating vesicle biogenesis

Paczkowski¹,

Richardson

Fromme

2015

Trends in Cell Biology

View full text Add to dashboard Cite

Cargo adaptors sort transmembrane protein cargos into nascent vesicles by binding directly to their cytosolic domains. Recent studies have revealed previously unappreciated roles for cargo adaptors and regulatory mechanisms governing their function. The AP-1 and AP-2 clathrin adaptors switch between open and closed conformations that ensure they function at the right place at the right time. The exomer cargo adaptor plays a direct role in remodeling the membrane for vesicle fission. Several different cargo adaptors functioning in distinct trafficking pathways at the Golgi are similarly regulated through bivalent binding to the Arf1 GTPase, potentially enabling regulation by a threshold concentration of Arf1. Taken together, these studies highlight that cargo adaptors do more than just adapt cargos.

show abstract

Section: Copii Coat Assembly May Accommodate Different Cargo Sizessupporting

confidence: 58%

Cargo adaptors: structures illuminate mechanisms regulating vesicle biogenesis

Paczkowski¹,

Richardson

Fromme

2015

Trends in Cell Biology

View full text Add to dashboard Cite

show abstract

“…This observation seems to suggest that - despite the preference of the COPII coat for high-curvature structures seen by fluorescence – COPII proteins have some flexibility for binding to lower curvature membranes. The ability of the COPII coat to bind to membranes of different curvatures merits further investigation to determine how COPII cages form on ‘oversized' cargo such as procollagen and chylomicrons1213.…”

Section: Resultsmentioning

confidence: 99%

Multibudded tubules formed by COPII on artificial liposomes

Bacia

Futai

Prinz

et al. 2011

Sci Rep

View full text Add to dashboard Cite

COPII-coated vesicles form at the endoplasmic reticulum for cargo transport to the Golgi apparatus. We used in vitro reconstitution to examine the roles of the COPII scaffold in remodeling the shape of a lipid bilayer. Giant Unilamellar Vesicles were examined using fast confocal fluorescence and cryo-electron microscopy in order to avoid separation steps and minimize mechanical manipulation. COPII showed a preference for high curvature structures, but also sufficient flexibility for binding to low curvatures. The COPII proteins induced beads-on-a-string-like constricted tubules, similar to those previously observed in cells. We speculate about a mechanical pathway for vesicle fission from these multibudded COPII-coated tubules, considering the possibility that withdrawal of the Sar1 amphipathic helix upon GTP hydrolysis leads to lipid bilayer destabilization resulting in fission.

show abstract

“…This might occur because, whereas cargo-free self-assembled COPII vesicles are 40–80 nm in diameter (Barlowe et al, 1994; Miller and Barlowe, 2010; Dancourt and Barlowe, 2010), fibrillar procollagen bundles form rigid 300 nm rods (Fraser et al, 1979; Stephens and Pepperkok, 2002; Canty and Kadler, 2005). Hence, collagen transport requires specialized, oversized COPII structures and an ample supply of coat proteins (Stagg et al, 2008; O’Donnell et al, 2010). As a result, in cells with high levels of protein trafficking, the availability of COPII carriers might become a limiting factor, and other proteins might displace collagen molecules.…”

Section: Discussionmentioning

confidence: 99%

Thefeelgoodmutation in zebrafish dysregulates COPII-dependent secretion of select extracellular matrix proteins in skeletal morphogenesis

Melville

Montero-Balaguer

Levic

et al. 2011

Disease Models &Amp; Mechanisms

View full text Add to dashboard Cite

SUMMARYCraniofacial and skeletal dysmorphologies account for the majority of birth defects. A number of the disease phenotypes have been attributed to abnormal synthesis, maintenance and composition of extracellular matrix (ECM), yet the molecular and cellular mechanisms causing these ECM defects remain poorly understood. The zebrafish feelgood mutant manifests a severely malformed head skeleton and shortened body length due to defects in the maturation stage of chondrocyte development. In vivo analyses reveal a backlog of type II and type IV collagens in rough endoplasmic reticulum (ER) similar to those found in coat protein II complex (COPII)-deficient cells. The feelgood mutation hinders collagen deposition in the ECM, but trafficking of small cargos and other large ECM proteins such as laminin to the extracellular space is unaffected. We demonstrate that the zebrafish feelgood mutation causes a single amino acid substitution within the DNA-binding domain of transcription factor Creb3l2. We show that Creb3l2 selectively regulates the expression of genes encoding distinct COPII proteins (sec23a, sec23b and sec24d) but find no evidence for its regulation of sec24c expression. Moreover, we did not detect activation of ER stress response genes despite intracellular accumulation of collagen and prominent skeletal defects. Promoter trans-activation assays show that the Creb3l2 feelgood variant is a hypomorphic allele that retains approximately 50% of its transcriptional activity. Transgenic rescue experiments of the feelgood phenotype restore craniofacial development, illustrating that a precise level of Creb3l2 transcriptional activity is essential for skeletogenesis. Our results indicate that Creb3l2 modulates the availability of COPII machinery in a tissue- and cargo-specific manner. These findings could lead to a better understanding of the etiology of human craniofacial and skeletal birth defects as well as adult-onset diseases that are linked to dysregulated ECM deposition, such as arthritis, fibrosis or osteoporosis.

show abstract

The structure of a COPII tubule

Cited by 18 publications

References 37 publications

Cargo adaptors: structures illuminate mechanisms regulating vesicle biogenesis

Cargo adaptors: structures illuminate mechanisms regulating vesicle biogenesis

Multibudded tubules formed by COPII on artificial liposomes

Thefeelgoodmutation in zebrafish dysregulates COPII-dependent secretion of select extracellular matrix proteins in skeletal morphogenesis

Contact Info

Product

Resources

About