TY  - JOUR
AU  - Czajka, Titus
AU  - Major, Andras
AU  - Bruns, Hendrik
AU  - Cammarata, Marco
AU  - Hoffmann, Christian
AU  - Milovanovic, Dragomir
AU  - Salditt, Tim
TI  - Vesicle dynamics in synapsin-induced condensates by passive X-ray microrheology.
JO  - Biophysical journal
VL  - 125
IS  - 7
SN  - 0006-3495
CY  - Cambridge, Mass.
PB  - Cell Press
M1  - DZNE-2026-00384
SP  - 1713 - 1722
PY  - 2026
AB  - The collective dynamics of subcellular biological processes is often difficult to assess experimentally due to the challenges associated with spatial and temporal resolution, labeling, or multiple scattering. X-ray photon correlation spectroscopy is, in principle, well suited to probe collective dynamics by quantifying dispersion relations in complex fluids in general and biomolecular systems in particular. However, the low scattering signal and the sensitivity to radiation damage set stringent limits to many applications. Probing the dynamics of vesicles in protein-induced condensates is a case in point. Here, we use lipid vesicles with a hard silica core, called colloid-supported lipid bilayers, as labeled vesicles for enhanced X-ray contrast. We then probe structure and dynamics in solutions of vesicles and synapsin, a protein known for its property of inducing liquid-liquid phase separation and forming condensates that recruit vesicles, organizing them into clusters in presynaptic nerve terminals. The dynamics in these systems is found to exhibit evidence for both liquid-like and network-like phases. Our results reveal distinct effective-diffusion constants at varying protein concentrations. At the same time the stretched exponential decay of the correlation functions provides clear evidence for nondiffusive behavior within the condensates.
KW  - Lipid Bilayers: chemistry
KW  - Lipid Bilayers: metabolism
KW  - Synapsins: metabolism
KW  - Synapsins: chemistry
KW  - Diffusion
KW  - X-Rays
KW  - Biomolecular Condensates: chemistry
KW  - Biomolecular Condensates: metabolism
KW  - Lipid Bilayers (NLM Chemicals)
KW  - Synapsins (NLM Chemicals)
LB  - PUB:(DE-HGF)16
C6  - pmid:41795188
DO  - DOI:10.1016/j.bpj.2026.03.006
UR  - https://pub.dzne.de/record/286088
ER  -