Cryo-electron tomography reveals how COPII assembles on cargo-containing membranes

TY - JOUR

T1 - Cryo-electron tomography reveals how COPII assembles on cargo-containing membranes

AU - Pyle, Euan

AU - Miller, Elizabeth A.

AU - Zanetti, Giulia

PY - 2024/11/7

Y1 - 2024/11/7

N2 - Proteins traverse the eukaryotic secretory pathway through membrane trafficking between organelles. The coat protein complex II (COPII) mediates the anterograde transport of newly synthesized proteins from the endoplasmic reticulum, engaging cargoes with a wide range of size and biophysical properties. The native architecture of the COPII coat and how cargo might influence COPII carrier morphology remain poorly understood. Here we reconstituted COPII-coated membrane carriers using purified Saccharomyces cerevisiae proteins and cell-derived microsomes as a native membrane source. Using cryo-electron tomography with subtomogram averaging, we demonstrate that the COPII coat binds cargo and forms largely spherical vesicles from native membranes. We reveal the architecture of the inner and outer coat layers and shed light on how spherical carriers are formed. Our results provide insights into the architecture and regulation of the COPII coat and advance our current understanding of how membrane curvature is generated.

AB - Proteins traverse the eukaryotic secretory pathway through membrane trafficking between organelles. The coat protein complex II (COPII) mediates the anterograde transport of newly synthesized proteins from the endoplasmic reticulum, engaging cargoes with a wide range of size and biophysical properties. The native architecture of the COPII coat and how cargo might influence COPII carrier morphology remain poorly understood. Here we reconstituted COPII-coated membrane carriers using purified Saccharomyces cerevisiae proteins and cell-derived microsomes as a native membrane source. Using cryo-electron tomography with subtomogram averaging, we demonstrate that the COPII coat binds cargo and forms largely spherical vesicles from native membranes. We reveal the architecture of the inner and outer coat layers and shed light on how spherical carriers are formed. Our results provide insights into the architecture and regulation of the COPII coat and advance our current understanding of how membrane curvature is generated.

U2 - 10.1038/s41594-024-01413-4

DO - 10.1038/s41594-024-01413-4

M3 - Article

C2 - 39511455

SN - 1545-9993

VL - 32

SP - 513

EP - 519

JO - Nature Structural & Molecular Biology

JF - Nature Structural & Molecular Biology

ER -