Related Experiment Video
Updated: Oct 1, 2025

Isolation of Viral Replication Compartment-enriched Sub-nuclear Fractions from Adenovirus-infected Normal Human Cells
Published on: November 12, 2015
Human cytomegalovirus forms phase-separated compartments at viral genomes to facilitate viral replication
Enrico Caragliano1, Stefano Bonazza2, Giada Frascaroli2
1Leibniz Institute for Experimental Virology (HPI), 20251 Hamburg, Germany; Centre for Structural Systems Biology, 22607 Hamburg, Germany; Institute of Virology, Hannover Medical School, 30625 Hannover, Germany.
Abstract:
Human cytomegalovirus (HCMV) replicates its DNA genome in specialized replication compartments (RCs) in the host cell nucleus. These membrane-less organelles originate as spherical structures and grow in size over time. However, the mechanism of RC biogenesis has remained understudied. Using live-cell imaging and photo-oligomerization, we show that a central component of RCs, the UL112-113 proteins, undergo liquid-liquid phase separation (LLPS) to form RCs in the nucleus. We show that the self-interacting domain and large intrinsically disordered regions of UL112-113 are required for LLPS. Importantly, viral DNA induces local clustering of these proteins and lowers the threshold for phase separation. The formation of phase-separated compartments around viral genomes is necessary to recruit the viral DNA polymerase for viral genome replication. Thus, HCMV uses its UL112-113 proteins to generate RCs around viral genomes by LLPS to ensure the formation of a pro-replicative environment.
Related Concept Videos
Viruses with RNA Genomes
Viral Recombination
Size and Structure of Viral Genomes
Viral Structure
DNA Bacteriophages
Retrovirus Life Cycles

