Biology subjects

Muehlberg, L.

Publications and source records attributed to Muehlberg, L..

4 recordsLinked to original sources

bioRxiv2026

Virion-wide interactome mapping of HSV-1 reveals maturation-dependent remodeling and convergent organization of herpesvirus tegument networks

Herpesvirus virions form by remodeling of intracellular virus-host interaction networks into evolutionarily conserved particle architectures. Here, we define a virion-wide spatial and quantitative protein proximity map of herpes simplex virus 1 (HSV-1) by combining cross-linking mass spectrometry with quantitative proteomics. Integration with intracellular interaction maps reveals that maturation acts as a selective filter, transforming broad virus-host associations into an organized virion network. This process depletes biosynthetic and nuclear components while enriching interactions involved in tegument organization and envelope acquisition around the viral protein UL49. Comparison with analogous maps of human cytomegalovirus (HCMV) identifies HSV-1-UL49 and HCMV-UL32 as functionally equivalent network hubs despite lacking evolutionary relatedness. Both hubs converge on shared phosphoregulatory host factors, short linear interaction motifs, and liquid-liquid phase separation. At the virion surface, the host complement regulator CD59 protects particles from complement-mediated inactivation. Together, these findings show how conserved organizational principles shape virus-specific virion interaction networks during herpesvirus maturation.

microbiology↗

bioRxiv2026

Phosphorylation-tuned condensation links HCMV tegument assembly to membrane recruitment

Herpesviruses build complex infectious particles around a protein layer, the tegument, that lacks an ordered architecture. How this apparently amorphous material selectively assembles on the capsid and engages enveloping membranes remains unclear. Here we show that the capsid-anchored human cytomegalovirus protein pp150 forms liquid-like condensates when locally concentrated. Its disordered region recruits soluble tegument proteins and membrane-associated partners, providing a mechanism to couple assembly of the tegument layer to recruitment of the enclosing membrane. Phosphorylation tunes this condensation: phosphomimetic mutations prevent recovery of infectious virus, whereas loss of phosphorylation sites causes aberrant capsid-tegument assemblies and impairs viral replication. Together, these findings identify regulated condensation as a mechanism that couples tegument assembly to membrane recruitment and supports the production of infectious particles, highlighting condensate regulation as a potentially novel point of antiviral intervention.

microbiology↗

bioRxiv2025

Integrative structural interactomics reveals protein organization and structure in a giant virus

Giant viruses are large DNA viruses that infect unicellular and multicellular eukaryotes and form exceptionally large extracellular particles. (Meta)genomics and (meta)transcriptomics have provided insight into their diverse coding repertoire, but many of the proteins remain to be characterized as they lack homology with known proteins. Here, we integrated cross-linking mass spectrometry, quantitative proteomics, computational tools and cryo-EM data to characterize the protein architecture of intact melbournevirus particles. Based on this, we allocated 88 viral proteins to different virion sub-compartments and proposed topologies of 25 inner membrane proteins. We assigned eight components of the capsid in cryo-EM data, including proteins that tether the capsid shell to the membrane, reflecting key points in virion maturation. The data provide a valuable resource and demonstrate the power of an integrative approach to gain system-level structural insights into a poorly characterized biological system.

biochemistry↗

bioRxiv2025

Snapshot of in-cell protein contact sites reveals new host factors and hijacking of paraspeckles during influenza A virus infection

Influenza A virus (IAV) hijacks host cellular machinery, but many virus-IAV interactions and contacting protein sites remain uncharacterised, particularly those dependent on intact cellular architecture, such as membrane-associated or phase-separated compartments. Here, we applied in-cell cross-linking mass spectrometry (XL-MS), integrated with AlphaFold-based structural modelling and functional assays, to map protein-protein contact sites in IAV-infected human cells. This approach revealed previously unrecognised virus-host interactions linked to spatially organised processes, including the maturation pathway of HA through the membrane-bound ER- Golgi system, the novel interaction of M2 with the membrane-embedded LAT1 amino acid transporter, and the progressive disassembly of paraspeckles-phase-separated compartments in the nucleus. We validate M2-LAT1 interaction and paraspeckle disassembly in human primary lung epithelial cells and show that the paraspeckle disassembly constitutes a new and unique infection mechanism through which IAV releases RNA-binding proteins that support viral RNA replication. These findings advance the understanding of IAV manipulation of host cellular processes and illustrate how the integrative in-cell structural system biology approach captures native host-pathogen interactomes, infection pathways, and host cell perturbations.

microbiology↗