Molecular Flexibility and Electrostatic Interactions Drive the Nanoscale Structure of Coiled-Coil GM130 Protein Condensates
Abstract
Golgins are coiled-coil proteins that decorate Golgi cisternae with highly specific spatial distribution acting as vesicle tethers through their extended, semiflexible architectures. Among them, GM130 is also known to undergo phase separation, yet the molecular basis of this behavior remains poorly understood. Here, we use atomic force microscopy (AFM) to directly visualize individual GM130 molecules adsorbed onto attractive surfaces. We find that GM130 is highly flexible and undergoes conformational transitions from extended chains to collapsed coils-globular structures that serve as building blocks for the submicrometric two-dimensional and dynamic domains when anchored to lipid bilayers. Molecular-dynamics simulations predict a supramolecular scaffold for GM130 domains composed of coiled-coil intermolecular nodes surrounded by a dispersed phase of intrinsically disordered regions with electrostatic interactions acting as chief drivers of phase-separation. These assemblies are experimentally validated under high-force AFM measurements. Our findings establish the structural basis linking GM130 conformational polymorphism to its phase separation capacity.
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BibTeX
@article{mateosgil2026molecular,
title = {{Molecular Flexibility and Electrostatic Interactions Drive the Nanoscale Structure of Coiled-Coil GM130 Protein Condensates}},
author = {Pablo Mateos-Gil and Alejandro Feito and Daniel González Cava and Andrés R Tejedor and Víctor G Almendro-Vedia and Jeff Coleman and Hong Zheng and Michaela Simanjuntak and Jean N D Goder and James E Rothman and Jorge R Espinosa and Frederic Pincet and Iván López-Montero},
journal = {PRX Life},
year = {2026},
month = may,
doi = {10.1103/lp87-svtc},
url = {https://hal.science/hal-05754235v1},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Molecular Flexibility and Electrostatic Interactions Drive the Nanoscale Structure of Coiled-Coil GM130 Protein Condensates
AU - Pablo Mateos-Gil
AU - Alejandro Feito
AU - Daniel González Cava
AU - Andrés R Tejedor
AU - Víctor G Almendro-Vedia
AU - Jeff Coleman
AU - Hong Zheng
AU - Michaela Simanjuntak
AU - Jean N D Goder
AU - James E Rothman
AU - Jorge R Espinosa
AU - Frederic Pincet
AU - Iván López-Montero
PY - 2026
DA - 2026/05/28
JO - PRX Life
DO - 10.1103/lp87-svtc
UR - https://hal.science/hal-05754235v1
AB - Golgins are coiled-coil proteins that decorate Golgi cisternae with highly specific spatial distribution acting as vesicle tethers through their extended, semiflexible architectures. Among them, GM130 is also known to undergo phase separation, yet the molecular basis of this behavior remains poorly understood. Here, we use atomic force microscopy (AFM) to directly visualize individual GM130 molecules adsorbed onto attractive surfaces. We find that GM130 is highly flexible and undergoes conformational transitions from extended chains to collapsed coils-globular structures that serve as building blocks for the submicrometric two-dimensional and dynamic domains when anchored to lipid bilayers. Molecular-dynamics simulations predict a supramolecular scaffold for GM130 domains composed of coiled-coil intermolecular nodes surrounded by a dispersed phase of intrinsically disordered regions with electrostatic interactions acting as chief drivers of phase-separation. These assemblies are experimentally validated under high-force AFM measurements. Our findings establish the structural basis linking GM130 conformational polymorphism to its phase separation capacity.
SN - 2835-8279
SN - 2835-8279
ER -