Biology subjects

Biteen, J. S.

Publications and source records attributed to Biteen, J. S..

At least 19 recordsLinked to original sources

bioRxiv2026

Fluorescent Biosensors for Cryogenic Correlative Light and Electron Microscopy

Cryogenic electron tomography provides nanometer-scale views of subcellular structures but lacks essential physiological context, such as the metabolic state or ion concentration. To bridge this gap, we incorporated fluorescent biosensors into a cryogenic correlative light and electron microscopy workflow, enabling direct measurement of physiological conditions alongside structural data. Here, we focused on establishing and calibrating biosensors for calcium, pH, and osmotic stress at cryogenic conditions through an in vitro workflow in which biosensors were frozen in defined chemical environments and then imaged ratiometrically. We then applied these biosensors across a range of sample types: an osmotic stress sensor in Saccharomyces cerevisiae, a calcium sensor in human U2OS cells, and a pH sensor in the bacterium Halothiobacillus neapolitanus. This approach links localized physiological changes to the 3D structures of macromolecules and their organization in situ.

biophysics↗

bioRxiv2026

Substrate recognition, not sequestration, drives the engagement of an H3K9 methyltransferase in living cells

The histone H3K9 methyltransferase Clr4 is essential for heterochromatin formation in Schizosaccharomyces pombe, yet how it searches for and engages chromatin in vivo remains unclear. Using live-cell single-molecule tracking of PAmCherry-Clr4, we quantified how perturbations to Clr4 alter its diffusion, search behavior, and residence times. Chromodomain and SET-domain Clr4 mutants move faster and more isotropically and have reduced residence times at heterochromatin, reflecting impaired substrate recognition. In contrast, deleting Swi6, which has been proposed to sequester Clr4, does not reduce the slow-state fraction or alter Clr4 diffusion, indicating that chromatin engagement is intrinsic to Clr4 rather than HP1-dependent. Anisotropy analysis at short and intermediate displacements indicates that Clr4 does not explore chromatin by simple three-dimensional diffusion but through a guided, distance-dependent search in which it repeatedly samples nearby nucleosomes before disengaging. Across all other perturbations we examined, such as deletion of the CLRC component Rik1, impaired Clr4 ubiquitination, and using cells with an unmethylatable H3K9R substrate, Clr4 dynamics were only modestly affected, and a chromatin-associated population persisted in every background. This robustness indicates that the chromodomain and SET domains are the primary determinants of how Clr4 engages chromatin in vivo, allowing it to continuously sample the genome while maintaining a stable bound population. Our results suggest how the promiscuous sampling of chromatin may also enable Clr4 to establish novel sites of heterochromatin during adaptation.

biophysics↗

bioRxiv2026

Polyphosphate acts as an architectural regulator of carbon fixation and nucleoid structure in cyanobacteria

Polyphosphate (polyP) is a conserved inorganic polymer traditionally viewed as a stress-induced phosphate and energy reserve. In cyanobacteria, however, polyP granules are constitutively present and frequently observed in proximity to carboxysomes, the bacterial microcompartments that mediate CO2 fixation. Here we show that polyP functions as a spatially organized regulator of the photosynthetic cytoplasm in Synechococcus elongatus. PolyP granules localize to the nucleoid and are periodically arranged along the cell axis, independently of the McdAB carboxysome positioning system. Despite this independence, polyP and carboxysomes associate non-randomly, and this association is enhanced when active carboxysome positioning by the McdAB system is disrupted. Loss of polyP synthesis leads to nucleoid expansion, an increased number of smaller carboxysomes with high mobility, and severe defects in growth under ambient CO2. Perturbation of polyP turnover further reveals structural connections to both carboxysomes and thylakoid membranes. Together, these findings identify polyP as an architectural integrator that couples chromosome organization, metabolic compartmentalization, and photosynthetic fitness.

microbiology↗

bioRxiv2026

The kinetics and mobility of a ParA ATPase drive carboxysome distribution in Halothiobacillus neapolitanus

Carboxysomes are bacterial microcompartments that drive efficient carbon fixation in autotrophic bacteria. Critical to their function and inheritance is their spatial organization by the ParA-type ATPase, McdA, and its partner protein, McdB. Here, we investigate the -carboxysome McdAB system in Halothiobacillus neapolitanus using biochemical assays, quantitative fluorescence imaging, and mathematical modeling. We find that, unlike most ParA-type ATPases, the ATPase activity of McdA is only stimulated by DNA rather than by its partner protein McdB. Despite this difference, McdB conserves the ability to displace McdA from DNA, suggesting that ATP hydrolysis and DNA unbinding by McdA are not strictly coupled. Together with its ability to diffuse while bound to DNA, McdA forms gradients on the nucleoid that prevent carboxysome aggregation via a Brownian ratchet mechanism. Overall, these findings reveal key differences in a ParA-type ATPase that may be specific for the spatial organization of protein-based organelles in bacteria.

biophysics↗

bioRxiv2026

The biophysical properties of the bacterial nucleoid are dynamic, heterogeneous, and responsive to perturbations of cellular processes

Biophysical properties play central roles in cellular function by controlling the diffusion and spatial organization of biomolecules. Because bacteria lack a nuclear membrane, biophysical measurements are often averaged over the entire cell. However, the nucleoid environment is distinct from that of the surrounding cytoplasm, and averaging also ignores local characteristics within the nucleoid. Here, we developed a microrheology framework to quantitatively characterize the bacterial nucleoid and investigate the interplay of its physical properties with cellular processes. We combined single-particle tracking of a genetically encoded protein probe and three-dimensional (3D) Brownian dynamics simulations to separate the nucleoid from the cytoplasm and specifically measure nucleoid accessibility and viscosity. We found that the nucleoid viscosity is 2.5-fold higher than the cytoplasmic viscosity, and that both viscosity and accessibility change systematically across growth phases and the cell cycle. Inhibiting transcription or translation produces opposite changes in nucleoid viscosity in exponential versus stationary phase cells, indicating that the regulation of nucleoid viscosity is sensitive to the underlying biomolecular composition, crowding, and spatial organization. Using Hi-C assays, we further show that changes in nucleoid viscosity may occur without detectable alterations in genome organization, which suggests that nucleoid mechanics provide an independent regulatory mechanism. Spatially, viscosity differences are more pronounced between the nucleoid core and periphery than between genomic locations, and the periphery-core contrast correlates with the coupling of transcription, translation, and membrane insertion. Together, these results indicate that the bacterial nucleoid is a dynamic, heterogeneous viscoelastic environment in which actively regulated biophysical properties may help coordinate multiple cellular processes and provide a physical layer of control that complements canonical biochemical regulation.

biophysics↗

bioRxiv2025

Characterizing the Impact of Nucleoid-Associated Proteins on HU-DNA Interactions by Live-Cell Single-Molecule Tracking

The bacterial nucleoid undergoes extensive structural reorganization during growth, influenced by nucleoid-associated proteins (NAPs) whose interactions and effects on nucleoid organization remain unclear. We investigated these interactions by tracking single molecules of the NAP HU-PAmCherry in living Escherichia coli cells in different growth phases, and we further examined how two NAPs, Dps and H-NS, impact HU dynamics. HU mobility varies with growth phase: In exponential phase, HU has two distinct mobility states: a fast-diffusing state and a slower, interacting state. In stationary phase, we observed a third population of very slow molecules, suggesting stable HU binding or confinement within compacted DNA. Deleting dps increases HU mobility in stationary phase, consistent with findings that Dps promotes short-range DNA contacts and nucleoid compaction in deep stationary phase. We measured in exponential phase that hns deletion leads to nucleoid compaction, faster HU diffusion, and a third population of very slow HU molecules in these cells. In stationary phase, deleting hns increases these stably bound HU molecules. Our results show that growth-phase-dependent nucleoid reorganization by Dps and H-NS influences the behavior and function of other NAPs. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=55 SRC="FIGDIR/small/695591v2_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@16d8f9forg.highwire.dtl.DTLVardef@1f03355org.highwire.dtl.DTLVardef@ba1fc7org.highwire.dtl.DTLVardef@17c5de2_HPS_FORMAT_FIGEXP M_FIG C_FIG The nucleoid-associated proteins Dps, H-NS, and HU shape the bacterial chromosome in the deep stationary phase through their interactions with the nucleoid.

biophysics↗

bioRxiv2025

Single-molecule tracking of RNA-DNA hybrid removal enzymes important for lagging-strand replication

The formation of RNA-DNA hybrid (RDH) primers by primase is an essential step in the recruitment of DNA polymerase during replication initiation and for the synthesis of each Okazaki fragment on the lagging strand. In addition to primers, RDHs form through misincorporation of ribonucleotides by DNA polymerase during elongation and by formation of R-loops during transcription. R-loops are three-stranded structures that form when the nascent mRNA anneals to the template DNA strand, displacing the complementary DNA strand. The persistence of RDHs is deleterious to genome stability in all cells because they increase susceptibility to mutations, impaired replication fork progression, DNA double-stranded breaks, and genomic rearrangements. In many bacteria, it is well established that components of the replicative DNA polymerase form a macromolecular complex that can be imaged using single-molecule or ensemble fluorescence approaches. The spatiotemporal regulation of proteins involved in RDH removal during lagging-strand maturation is less clear. Here, we study three proteins that are involved in the removal of RDHs from the lagging strand during DNA replication in the Gram-positive bacterium Bacillus subtilis: DNA polymerase I (Pol I), FenA, and RNase HIII. We characterized the behavior of each PAmCherry-tagged lagging-strand enzyme in living cells using single-particle tracking photactivated localization microscopy. In this work, we find that all three proteins are highly mobile, suggesting residence times at their target substrates are below our temporal resolution. We also find evidence that Pol I activity is modulated through interaction with the replisome, whereas FenA and RNase HIII are regulated through access to the nucleoid. Our results provide new insight into how enzymes are recruited to resolve RDHs during lagging-strand replication in vivo. SignificanceRNA-DNA hybrids (RDHs) are essential, transient intermediates in DNA replication, yet their presence significantly increases the susceptibility of the genome to damage. We characterized the single-molecule behavior of three proteins important for processing RDHs in Okazaki fragments in living bacteria. We find that enzyme activity is modulated by access to the replisome and nucleoid. Specifically, we find that DNA polymerase I is preferentially localized to the replisome, while FenA and RNase HIII dwell times at the replisome are very short and below our detection limit. Our work shows that Pol I, FenA, and RNase HIII turn over rapidly in cells, providing new insight into how lagging-strand replication is coordinated in vivo.

biophysics↗

bioRxiv2025

Genome-wide DNA bridging by H-NS reshapes the stationary phase nucleoid and transcriptional landscape

Bacterial nucleoid-associated proteins (NAPs) structure the chromosome and regulate gene expression, but how these two functions are related is unclear. H-NS is a well-studied NAP that acts as a global gene silencer capable of bridging and looping DNA in vitro. Here, using high-throughput chromosome conformation capture assays, we show that H-NS mediates genome-wide long-range DNA looping in the stationary-phase nucleoid of Escherichia coli. Chromatin immunoprecipitation assays demonstrate that high levels of H-NS are present at the base of DNA loops. Super-resolution imaging and single-particle tracking show that H-NS binds more tightly in stationary phase and compacts the nucleoid mesh. Transcriptomic analyses indicate H-NS represses gene expression more strongly in the looped nucleoid and enables higher expression of genes outside of H-NS-bound regions. Overall, our study demonstrates that H-NS bridges distal DNA regions along the genome upon nutrient limitation, causing reduced nucleoid accessibility, stronger transcriptional repression, and a shifted transcriptional landscape.

molecular biology↗

bioRxiv2025

Dps binds and protects DNA in starved Escherichia coli with minimal effect on chromosome accessibility, dynamics and organisation

Dps is the most abundant nucleoid-associated protein in starved Escherichia coli with [~]180,000 copies per cell. Dps binds DNA and oxidises iron, facilitating survival in harsh environments. Dps-DNA complexes can form crystalline structures, leading to the proposed model that Dps reorganises the starved E. coli nucleoid into a compact liquid crystal, slowing chromosome dynamics and limiting access of other proteins to DNA. In this work, we directly tested this model using live-cell super-resolution microscopy and Hi-C analysis. We found that after 96 h of starvation, Dps compacts the nucleoid and increases short-range DNA-DNA interactions, but does not affect chromosome accessibility to large protein nanocages or small restriction enzymes. We also report that chromosome dynamics and organisation are primarily impacted by the bacterial growth phase; the effect of Dps is relatively minor. Our work clarifies the role of Dps in modulating nucleoid properties, and we propose an updated model for Dps-DNA interactions in which Dps binds, protects and compacts DNA largely without influencing chromosome access, dynamics and organisation. Additionally, this work provides a general framework for assessing the impact of nucleoid-associated proteins on key aspects of chromosome function in live cells. TOC O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=82 SRC="FIGDIR/small/673347v3_ufig1.gif" ALT="Figure 1"> View larger version (36K): org.highwire.dtl.DTLVardef@1385efforg.highwire.dtl.DTLVardef@1e4cb76org.highwire.dtl.DTLVardef@1e9e43dorg.highwire.dtl.DTLVardef@8768f4_HPS_FORMAT_FIGEXP M_FIG C_FIG

biophysics↗

bioRxiv2025

Transient binding facilitates super-resolution imaging of functional amyloid fibrils on living bacteria

Curli, which are the major proteinaceous component of the Escherichia coli biofilm extracellular matrix, help protect cells against environmental stressors including dehydration and antibiotics. Composed of the amyloid proteins CsgA and CsgB, curli self-assemble as these protomers are secreted into the extracellular space. The mechanisms of curli assembly and their functional roles within the extracellular matrix are incompletely understood. High-resolution imaging tools compatible with live-cell conditions provide a critical means to investigate the assembly and function of curli in their native context. In this study, we use super-resolution imaging to visualize curli fibrils on living bacterial cells. Transient amyloid binding of the fluorogenic dye Nile blue facilitates two complementary super-resolution fluorescence microscopy approaches: single-molecule localization microscopy and super-resolution optical fluctuation imaging. Additionally, imaging fluorescence correlation spectroscopy was used to measure the characteristic relaxation times associated with Nile blue binding to CsgA fibrils. Together, these approaches offer a framework for imaging-based biophysical characterization of curli structures on living cells. Importance/impact statementEscherichia coli and other enteric bacteria secrete amyloid proteins that self-assemble into fibrillar structures called curli, forming a key component of biofilm extracellular matrices. Bacterial biofilms confer resilience to harsh environments with broad implications for human health. In this study, we extend transient amyloid binding to the novel application of super-resolution fluorescence microscopy of curli on living cells, offering promising approaches to gain structural and mechanistic insights.

biophysics↗

bioRxiv2025

Nucleoid Compaction Influences Carboxysome Localization and Dynamics in Synechococcus elongatus PCC 7942

The bacterial nucleoid is not just a genetic repository--it serves as a dynamic scaffold for spatially organizing key cellular components. ParA-family ATPases exploit this nucleoid matrix to position a wide range of cargos, yet how nucleoid compaction influences these positioning reactions remains poorly understood. We previously characterized the Maintenance of Carboxysome Distribution (Mcd) system in the cyanobacterium Synechococcus elongatus PCC 7942, where the ParA-like ATPase McdA binds the nucleoid and interacts with its partner protein, McdB, to generate dynamic gradients that distribute carboxysomes for optimal carbon fixation. Here, we investigate how nucleoid compaction impacts carboxysome positioning, particularly during metabolic dormancy when McdAB activity is downregulated. We demonstrate that a compacted nucleoid maintains carboxysome organization in the absence of active McdAB-driven positioning. This finding reveals that the nucleoid is not merely a passive substrate for positioning, but an active player in spatial organization. Given the widespread role of ParA-family ATPases in the positioning of diverse cellular cargos, our study suggests that nucleoid compaction state is a fundamental, yet underappreciated, determinant of mesoscale organization across bacteria.

microbiology↗

bioRxiv2025

HP-Bodies - Ancestral Condensates that Regulate RNA Turnover and Protein Translation in Bacteria

Uncovering what drives select biomolecules to form phase-separated condensates in vivo and identifying their physiological significance are topics of fundamental importance. Here we show that nitrogen-starved Escherichia coli produce long-chain polyphosphates, which scaffold the RNA chaperone Hfq into phase-separating high molecular weight complexes together with components of the RNA translation and processing machinery. The presence of polyphosphate within these condensates, which we termed HP-bodies, controls Hfq function by selectively stabilizing polyadenylated RNAs involved in transcription and protein translation, and promoting interactions with translation- and RNA-metabolism-associated proteins involved in de novo protein synthesis. Lack of polyphosphate prevents HP-body formation, which increases cell death and significantly hinders recovery from N-starvation. In functional analogy, we demonstrate that polyP contributes specifically to the formation of Processing (P)-bodies in human cell lines, revealing that a single, highly conserved and ancestral polyanion serves as the universal scaffold for functional phase-separated condensate formation across the tree of life.

microbiology↗

bioRxiv2024

Stress Changes the Bacterial Biomolecular Condensate Material State and Shifts Function from mRNA Decay to Storage

Bacterial ribonucleoprotein bodies (BR-bodies) are dynamic biomolecular condensates that play a pivotal role in RNA metabolism. We investigated how BR-bodies significantly influence mRNA fate by transitioning between liquid- and solid-like states in response to stress. With a combination of single-molecule and bulk fluorescence microscopy, biochemical assays, and quantitative analyses, we determine that BR-bodies promote efficient mRNA decay in a liquid-like condensate during exponential growth. On the other hand, BR-bodies are repurposed from sites of mRNA decay to reservoirs for mRNA storage under stress; a functional change that is enabled by their transition to a more rigid state, marked by reduced internal dynamics, increased molecular density, and prolonged residence time of ribonuclease E. Furthermore, we manipulated ATP levels and translation rates, and we conclude that the accumulation of ribosome-depleted mRNA is a key factor driving BR-body rigification, and that condensate maturation further contributes to this process. Upon nutrient replenishment, stationary-phase BR-bodies disassemble, releasing stored mRNAs for rapid translation, demonstrating that BR-body function is governed by a reversible mechanism for resource management. These findings reveal adaptive strategies by which bacteria regulate RNA metabolism through condensate-mediated control of mRNA decay and storage.

biophysics↗

bioRxiv2024

Nascent flagellar basal bodies are immobilized by rod assembly in Bacillus subtilis

Flagella are complex, trans-envelope nanomachines that localize to species- specific cellular addresses. Here we study the localization dynamics of the earliest stage of basal body formation in Bacillus subtilis using a fluorescent fusion to the C-ring protein FliM. We find that B. subtilis basal bodies do not exhibit dynamic subunit exchange and are largely stationary at steady state, consistent with flagellar assembly through the peptidoglycan. Rare basal bodies were observed to be mobile however, and the frequency of basal body mobility is elevated both early in basal body assembly and when the rod is mutated. Thus, basal body mobility is a precursor to patterning and we propose that rod polymerization probes the peptidoglycan superstructure for pores of sufficient diameter that permit rod completion. Furthermore, mutation of the rod also disrupts basal body patterning in a way that phenocopies mutation of the cytoplasmic flagellar patterning protein FlhF. We infer that conformational changes in the basal body exchange information between rod synthesis and the cytoplasmic patterning proteins to restrict assembly at certain pores established by a grid-like pattern pre-existent in the peptidoglycan itself. IMPORTANCEBacteria insert flagella in a species-specific pattern on the cell body, but how patterns are achieved is poorly understood. In bacteria with a single polar flagellum, a marker protein localizes to the cell pole and nucleates the assembly of the flagellum at that site. Bacillus subtilis assembles [~]15 flagella over the length of the cell body in a grid-like pattern and lacks all proteins associated with targeted assembly in polarly flagellated bacteria. Here we show that B. subtilis basal bodies are mobile soon after assembly and become immobilized when the flagellar rod transits the peptidoglycan wall. Moreover, defects in the flagellar rod lead to an asymmetric distribution of flagella with respect to the midcell. We conclude that the patterning of flagella is different in B. subtilis, and we infer that the B. subtilis rod probes the peptidoglycan for holes that can accommodate the machine.

cell biology↗

bioRxiv2023

Identification of a novel, tunable interface in the S.pombe HP1 protein, Swi6, that underpins epigenetic inheritance.

HP1 proteins are essential for establishing and maintaining transcriptionally silent heterochromatin. They dimerize, forming a binding interface to recruit diverse chromatin-associated factors. HP1 proteins are specialized and rapidly evolve, but the extent of variation required to achieve functional specialization is unknown. To investigate how changes in amino acid sequence impacts epigenetic inheritance, we performed a targeted mutagenesis screen of the S. pombe HP1 homolog, Swi6. Substitutions within an auxiliary surface adjacent to the HP1 dimerization interface produced Swi6 variants with divergent maintenance properties. Remarkably, substitutions at a single amino acid position led to the persistent gain or loss of epigenetic inheritance. These substitutions increased Swi6 chromatin occupancy in vivo and altered Swi6-protein interactions that reprogram H3K9me maintenance. We show that relatively minor changes in Swi6 amino acid composition can lead to profound changes in epigenetic inheritance which provides a redundant mechanism to evolve novel effector specificity.

molecular biology↗

bioRxiv2023

An experimental framework to assess biomolecular condensates in bacteria

High-resolution imaging of biomolecular condensates in living cells is essential for correlating their properties to those observed through in vitro assays. However, such experiments are limited in bacteria due to resolution limitations. Here we present an experimental framework that probes the formation, reversibility, and dynamics of condensate-forming proteins in Escherichia coli as a means to determine the nature of biomolecular condensates in bacteria. We demonstrate that condensates form after passing a threshold concentration, maintain a soluble fraction, dissolve upon shifts in temperature and concentration, and exhibit dynamics consistent with internal rearrangement and exchange between condensed and soluble fractions. We also discovered that an established marker for insoluble protein aggregates, IbpA, has different colocalization patterns with bacterial condensates and aggregates, demonstrating its applicability as a reporter to differentiate the two in vivo. Overall, this framework provides a generalizable, accessible, and rigorous set of experiments to probe the nature of biomolecular condensates on the sub-micron scale in bacterial cells.

microbiology↗

bioRxiv2023

H3K9 methylation enhances HP1-associated epigenetic silencing complex assembly and suppresses off-chromatin binding

Visualizing and measuring molecular-scale interactions in living cells represents a major challenge, but recent advances in microscopy are bringing us closer to achieving this goal. Single-molecule super-resolution microscopy enables high-resolution and sensitive imaging of the positions and movement of molecules in living cells. HP1 proteins are important regulators of gene expression because they selectively bind and recognize H3K9 methylated (H3K9me) histones to form heterochromatin-associated protein complexes that silence gene expression. Here, we extended live-cell single-molecule tracking studies in fission yeast to determine how HP1 proteins interact with their binding partners in the nucleus. We measured how genetic perturbations that affect H3K9me alter the diffusive properties of HP1 proteins and each of their binding partners based on which we inferred their most likely interaction sites. Our results indicate that H3K9me promotes specific complex formation between HP1 proteins and their interactors in a spatially restricted manner, while attenuating their ability to form off-chromatin complexes. As opposed to being an inert platform or scaffold to direct HP1 binding, our studies propose a novel function for H3K9me as an active participant in enhancing HP1-associated complex formation in living cells.

biophysics↗

bioRxiv2023

The BR-body proteome contains a complex network of protein-protein and protein-RNA interactions

Bacterial RNP bodies (BR-bodies) are non-membrane-bound structures that facilitate mRNA decay by concentrating mRNA substrates with RNase E and the associated RNA degradosome machinery. However, the full complement of proteins enriched in BR-bodies has not been defined. Here we define the protein components of BR-bodies through enrichment of the bodies followed by mass spectrometry-based proteomic analysis. We found 111 BR-body enriched proteins, including several RNA binding proteins, many of which are also recruited directly to in vitro reconstituted RNase E droplets, showing BR-bodies are more complex than previously assumed. While most BR-body enriched proteins that were tested cannot phase separate, we identified five that undergo RNA-dependent phase separation in vitro, showing other RNP condensates interface with BR-bodies. RNA degradosome protein clients are recruited more strongly to RNase E droplets than droplets of other RNP condensates, implying that client specificity is largely achieved through direct protein-protein interactions. We observe that some RNP condensates assemble with preferred directionally, suggesting that RNA may be trafficked through RNP condensates in an ordered manner to facilitate mRNA processing/decay, and that some BR-body associated proteins have the capacity to dissolve the condensate. Finally, we find that RNA dramatically stimulates the rate of RNase E phase separation in vitro, explaining the dissolution of BR-bodies after cellular mRNA depletion observed previously. Altogether, these results suggest that a complex network of protein-protein and protein-RNA interactions controls BR-body phase separation and RNA processing. HighlightsO_LIBR-body proteomics identified 111 proteins enriched in BR-bodies. C_LIO_LIBR-bodies associate with an interconnected network of RNP condensates. C_LIO_LIBR-body condensation is modulated by its interaction network. C_LIO_LIRNA is required for rapid BR-body condensation. C_LI Graphical AbstractSummary of the BR-body protein interactome. Lines between two protein circles represent a direct interaction.

microbiology↗