Biology subjects

Acharya, P.

Publications and source records attributed to Acharya, P..

At least 19 recordsLinked to original sources

bioRxiv2026

Peptide inhibitors recognize prefusion viral fusion proteins with heterogeneous stoichiometry and rapid kinetics

Peptide fusion inhibitors, an important class of antivirals, block viral entry by targeting fusion proteins required for membrane fusion. However, their interactions with intact trimeric fusion proteins remain elusive; direct observation of binding on virions or native-like trimers has been lacking. Here, we developed a single-molecule imaging platform to visualize peptide binding in real time. LP-98 bound HIV-1 Envelope (Env) trimers on virions and, unexpectedly, prefusion-stabilized soluble Env trimers, with higher affinity for virion-associated Env and, among soluble trimers, a mutant Env. RSV fusion-inhibiting T-118 and 4ca similarly engaged prefusion-stabilized fusion (F) trimers with rapid kinetics and high-nanomolar affinities. Binding to prefusion Env or F demonstrates that peptide inhibitors can act earlier than the canonical prehairpin-intermediate model suggests. Individual binding events revealed heterogeneous peptide-to-trimer stoichiometries, with single-peptide occupancy predominating, while stepwise and simultaneous events revealed multiple routes to higher occupancy. These findings expand the canonical model of peptide fusion inhibition and provide previously inaccessible mechanistic insights into how antiviral peptide fusion inhibitors act.

microbiology↗

bioRxiv2026

Sequential HIV-1 fusion protein gates control the initiation of host cell entry

HIV-1 fusion with host cells is initiated upon engagement of the viral envelope (Env) protein by its receptors and co-receptors. Receptor-induced conformational changes in the Env ectodomain expose the fusion machinery and position the HIV-1 fusion peptide for release and transit to the host membrane. However, no allosteric rearrangements in the envelope receptor/co-receptor binding domain that could induce fusion peptide release have been identified, and the trigger for the structural cascade that brings the viral and host membranes together remains unknown. Here, we identified two sequential conformational gates that control fusion peptide release, thereby facilitating its transition to the host membrane. We show that destabilizing a clasp holding the fusion peptide proximal motif enhances fusion peptide release, and that a coupled downstream gate controls the release of the receptor-binding gp120 subunit. Single-particle cryo-EM structures, biased and unbiased atomistic simulations, and functional experiments reveal that this process is controlled by shifts in the angular orientation of the gp120 subunits, induced by the geometries required for receptor and co-receptor binding. These results show how HIV-1 senses contact with the host cell to initiate fusion, thereby permitting viral entry.

molecular biology↗

bioRxiv2026

Rapid vaccine induction of macaque HIV-1 V2 Apex broadly neutralizing antibodies with immunogenetic signatures that are potentially translatable to humans

Due to the complex biology of HIV-1 broadly neutralizing antibodies (bnAbs), HIV-1 vaccines must target unmutated germline precursor antibodies with B cell receptors that have the appropriate specificity and genetic features to develop neutralization breadth. Previous work has shown that immunization or infection in macaques primes unmutated precursor antibodies that target the broadly neutralizing epitope composed of the second variable region and proximal glycans (termed V2-apex site) of HIV-1 envelope (Env). Macaque V2-apex bnAb precursors elicited thus far have homogeneous usage of the second reading frame of a diversity (D) gene found only in macaques, calling into question whether HIV-1 Env immunogens can elicit only this canonical, macaque-specific V2-apex antibody response, limiting human vaccination success. Here, we show that vaccination of rhesus macaques with Env conjugated to a ferritin nanoparticle (OPT4-scNP) rapidly elicited V2-apex bnAbs with distinct D gene segment usage and motifs that are not restricted only to macaques. After two priming immunizations, V2-apex antibodies with non-canonical HCDR3s exhibited greater neutralization potency and breadth than V2-apex antibodies with previously observed HCDR3 motifs. Following sequential boosting immunizations, a V2-apex bnAb lineage with a novel HCDR3-encoded EDGED motif increased its neutralization breadth, including neutralization of viral isolates bearing the N130 glycan, which shields the V2-apex from recognition. High-resolution structures of two members of this V2-apex bnAb lineage, called DH2050, defined a novel binding mode in which it used its EDGED motif to contact the C-strand peptide and the N160 glycan within the V2-apex site. Altogether, we define a novel bnAb binding mode to the V2 Apex and demonstrate that HIV-1 Env sequential vaccination elicits V2-apex bnAbs with immunogenetic signatures that are potentially translatable to the human immune system.

immunology↗

bioRxiv2026

Barrier Immune Memory is Promoted by Intestinal Epithelial Cell Presentation of Injected Bacterial Antigens

The contributions of antigen compartmentalization to recognition differences between CD4 and CD8 T cells have long been appreciated, but little is known of how subcellular localization of different antigens expressed by a single pathogen impacts T cell immunity. By tracking a clonal CD4 T cell response to its cognate epitope shuttled between different virulence proteins of the enteropathogenic bacterium, Citrobacter rodentium (Cr), we find a remarkable bias in the magnitude and quality of the response contingent on whether antigen remains bacterially associated or is introduced into intestinal epithelial cells colonized by the bacterium. Only proteins injected into the cytosol of colonocytes via the type 3 secretion system (T3SS) of Cr were found to recruit robust antigen-specific T cell responses to the infected mucosa and give rise to CD4 resident memory T (Trm) cells that populate the mucosal epithelium--and this required direct presentation of these antigens by infected epithelial cells. Single-cell transcriptomic analyses revealed that sustained, bidirectional epithelial-T cell communication was required both to elicit epithelial barrier-protective T cell help and to promote transcriptional networks that program a tissue-residency rather than central memory fate. These results establish a central role for antigen presentation by non-professional APCs in controlling memory fate decisions by CD4 T cells, with important implications for development of successful mucosal vaccines.

immunology↗

bioRxiv2026

Germline-somatic residue synergy reshapes antibody encounter state pathways to enhance HIV 1 recognition

Antibodies initiate antigen recognition through short-lived encounter states. These states are structurally distinct from the bound state and allow an antibody to reach the epitope from diverse approach angles. We previously showed that encounter states enable broadly neutralizing HIV-1 antibodies to access protected epitopes, but how these states evolve during affinity maturation is unknown. Here, we defined encounter-state ensembles for two intermediates in a glycan-dependent antibody clonal lineage using extensive molecular dynamics simulations and Markov state modeling. Somatic mutations in the more mature member did not stabilize the bound state. Instead, they created early glycan-mediated interactions that reoriented the antibody during approach and markedly increased the association rate. This reorientation redistributed productive encounter states across a larger antigen surface. This expanded the antigen surface area over which collisions led to productive binding. The modified encounter state landscape positioned germline residues for conserved contacts and provided a kinetic route that naturally bypasses steric barriers at the epitope. Together, these results show that affinity maturation can proceed by reshaping encounter pathways rather than altering the final complex, revealing a generalizable mechanism by which somatic-germline synergy enhances antigen recognition.

immunology↗

bioRxiv2026

Shared Maturation Pathways of HIV-1 Envelope-reactive V3-glycan bnAb Lineages in Human and Rhesus Macaque

ABSTRACTUnderstanding broadly neutralizing antibody (bnAb) lineage development in rhesus macaques (RMs) infected with Simian-HIV (SHIV) may inform HIV-1 vaccine designs. We analyzed HIV-1 envelope-antibody coevolution in 18 RMs infected by SHIV.BG505 (subtype A) and found highly conserved patterns of antibody recognition and Env escape, including in three animals that developed V3-glycan bnAbs. From one RM with V3-glycan targeted plasma breadth, we isolated 203 members of a single clonal Ab lineage designated DH1030. DH1030 Abs demonstrated striking genetic, functional and structural similarities with the human V3-glycan bnAb lineage DH270, which was isolated from an individual with subtype C HIV-1 CH848 infection. Notably, human-DH270 and macaque-DH1030 bnAbs shared early improbable mutations in HCDR2 that were critical for bnAb development. Thus, key improbable mutations and convergent patterns of antibody evolution and epitope recognition were shared across primate species and distinct HIV-1 subtypes, findings that may be leveraged in new HIV-1 vaccine designs. ONE SENTENCE SUMMARYBroadly neutralizing antibodies targeting HIV-1 envelope surface protein develop via a common maturation pathway across primate phylogeny.

immunology↗

bioRxiv2026

Distinct allosteric remodeling of HIV-1 Env dynamics on virions by gp41-directed antibodies reveals two modes of neutralization

HIV-1 envelope glycoprotein (Env), a gp120-gp41 trimer, undergoes coordinated conformational changes that drive membrane fusion and allow immune evasion by transiently concealing neutralization-sensitive epitopes. Most broadly neutralizing antibodies (bNAbs) target gp120, whereas a distinct subset recognizes conserved gp41 regions, such as the fusion peptide and the membrane-proximal external region; however, their impact on Env dynamics and associated neutralization mechanisms remains unclear. Using bioorthogonal tagging for single-molecule FRET, we monitored real-time bNAb-induced conformational sampling of Env on intact virions. Most gp41-directed bNAbs allosterically stabilized the prefusion-closed (PC) state, whereas the bivalent 10E8.4/iMab favored both PC and CD4-bound open (predominant) states. Antibodies redistributed the conformational populations of Env with modest kinetic effects, preserving the sequential transition pathway. These findings reveal two modes of neutralization for gp41-directed antibodies: fixing the prefusion-closed conformation and opening it, in both cases via long-range allosteric control of Env dynamics.

microbiology↗

bioRxiv2026

Establishment of Galleria mellonella as a Model for Achromobacter xylosoxidans Infection

Achromobacter xylosoxidans (Ax) is an emerging pathogen with a strong capacity to adapt to different niches, but its pathogenesis is poorly understood. To investigate the virulence of this versatile bacterium, alternative infection models are valuable. Galleria mellonella wax moth presents cost and ethical advantages as an in vivo infection model. Here, we investigate the utility of Galleria as a model of Ax infection and demonstrate that mortality following Ax infection in Galleria recapitulates survival outcomes observed in infected mice. We further show that the Galleria infection model can be used to examine antimicrobial activity against Ax. Visualization of hemocytes suggested that Ax was internalized into immune cells, similar to what is observed in vertebrate models. Overall, our work establishes Galleria mellonella as a model of Ax infection that mirrors disease severity and innate immune cell interactions in murine models.

microbiology↗

bioRxiv2025

Structural determination of the HIV-1 Variable Region 3 epitope of antibody 19b

The HIV-1 Envelope (Env) in its pre-receptor "closed" conformation is targeted by broadly neutralizing antibodies (bnAbs), while its receptor-bound "open" conformation, exposes immunodominant epitopes targeted by non-neutralizing antibodies. A human immunoglobin G (IgG) monoclonal antibody (mAb), 19b, binds an Env third variable (V3) loop epitope that is only exposed in the open Env conformation. Despite widespread use of 19b to detect the open Env conformation in immunoassays, its epitope has not yet been structurally defined. Here we determine crystal structures of ligand-free and V3 peptide-bound 19b Fab to visualize details of this interaction. 19b utilizes both its heavy and light chains to interact with the V3 loop. The 5-residue heavy chain complementarity-determining region (CDR H3) facilitates a hydrophobic pocket for V3 residues to associate with. 19b adopts a cradle binding mode with its CDRH1, CDRL2 and CDRL3 mediating interactions with V3 regions that flank the conserved GPGR/Q motif, without making substantial contacts with the GPGR arch region. Our high-resolution structures by elucidating the epitope, binding mode and the structural basis for the broad reactivity of 19b, fill a gap in our knowledge of a reagent that is widely used in immunoassays.

biochemistry↗

bioRxiv2025

An integrated workflow for structural virology with a 100 keV electron microscope

Cryo-EM has revolutionized structural biology, especially for flexible and heterogeneous samples, although access to high end microscopes that enable these studies remains a bottleneck. While 300 keV microscopes have been the go-to for high-resolution structural determination, they are expensive and restricted to institutional and national facilities needing specialized expertise, with access falling far short of the demand. Here, we present the user-managed operation of a cheaper 100 keV electron microscope within a structural biology laboratory enabling close integration with protein production, biochemical and biophysical studies. We provide details and considerations for the installation of the microscope, its day-to-day maintenance, and operations. Using virus surface glycoproteins as case studies, we illustrate the workflow from grid screening, data collection, and data processing, and provide examples of data quality. This user-administered setup provides a training platform for researchers at all levels, with beginners in cryo-EM achieving proficiency to independently operate the microscope within a month of regular use and training. We have demonstrated routine high-quality low-resolution reconstructions using a Ceta CMOS camera and high-resolution reconstructions enabling building of atomic models using a Falcon C direct detector. While there are several examples of facilities that manage cryo-EM and individual laboratories leveraging cryo-EM, we provide here the first demonstration of a modern group independently doing both successfully, something that has been talked about frequently but rarely seen.

biochemistry↗

bioRxiv2025

Targeting RARβ With a Stable Retinoic Acid Mimic Promotes Neurite Outgrowth, Neurogenesis, and Behavioral Recovery

Injury to the adult central nervous system triggers minimal axonal regeneration, partly due to the limited activation of intrinsic growth programs. Retinoic acid (RA) signaling has been shown to promote modest regenerative responses, but its clinical utility is restricted by poor biochemical stability and short-lived receptor engagement. Here, we report a tribenzamide-based small molecule DM04, that recapitulates RA-like transcriptional and phenotypic effects and enhances regenerative outcomes, independent of canonical RARE-dependent transactivation. DM04 promoted neurite outgrowth in primary neurons, upregulated canonical RA-responsive genes, and supported neural induction from human iPSCs. In a murine spinal injury model, DM04 treatment improved motor recovery. Transcriptomic analysis revealed shared target gene activation between RA and DM04, along with unique enrichment of extracellular matrix remodeling pathways. These findings establish DM04 as a small molecule based approach with dual efficacy in injury and developmental contexts, acting through a mechanism distinct from canonical RAR transactivation, and highlight its promise as a candidate for further preclinical investigation in neural repair.

neuroscience↗

bioRxiv2025

Achromobacter xylosoxidans isolates exhibit genome diversity, variable virulence, high levels of antibiotic resistance and potential intrahost evolution.

2. AbstractAchromobacter xylosoxidans is an emerging pathogen characterized by high levels of antibiotic resistance and increasing infection rates worldwide. This motile, opportunistic pathogen is widely distributed in the environment and can cause various infections, including pneumonia, bacteremia, endocarditis, meningitis, and others. In this study, we analyzed the population structure, antibiotic resistance profiles, and virulence factors of over 200 publicly available genomes. Core genome analysis revealed that A. xylosoxidans is highly adaptable, possessing a relatively small core genome. Antibiotic susceptibility testing of isolates from the United States revealed high resistance to multiple antibiotics. Our data show that imipenem/relebactam (IMR) is as effective against A. xylosoxidans as imipenem (IMI) alone, indicating that relebactam does not inhibit {beta}-lactamase activity in Achromobacter. The species features multiple secretion systems, including the Type III secretion system (T3SS) of the YscN family, which is similar to those found in Bordetella pertussis and Pseudomonas aeruginosa. Isolates collected from the same patients showed changes in cytotoxicity, flagella motility, biofilm and antibiotic resistance suggesting its dynamic adaptation to host environment. Intra-host evolved isolates, NIH-010, NIH-016 and NIH-018 demonstrated the loss of flagellar motility and variable cytotoxicity while exhibiting increased antibiotic resistance and enhanced biofilm formation. Sequence analysis suggests that NIH-016-3 has tyrosine to histidine mutation at position 330 near the FlhF Guanosine triphosphate (GTP)-binding domain that may affect flagellar assembly. Interestingly, virulence assays showed significant variation in the ability of different A. xylosoxidans isolates to induce cell death in in vitro models, suggesting its dynamic adaptation to host environment. 3. ImportanceThis study provides a comprehensive examination of Achromobacter xylosoxidans, an emerging pathogen of global concern due to its high antibiotic resistance and increasing clinical relevance. By analyzing over 200 genomes, we offer critical insights into the population structure, resistance mechanisms, and virulence factors of this species. The identification of a small core genome underscores its potential for genomic plasticity. The existence of multiple secretion systems highlights the great capacity of A. xylosoxidans as a pathogen. Variations in virulence among A. xylosoxidans isolates indicate the complexity of this pathogen underscoring the need for further studies on its virulence mechanisms. Evolution within the host includes the loss of motility-associated systems and enhanced antibiotic resistance and biofilm formation. This work showed that A. xylosoxidans are resistant to relebactam when combined with imipenem a combination effective in other bacteria. These findings emphasize the urgent need for targeted therapeutic strategies to combat this opportunistic pathogen.

microbiology↗

bioRxiv2025

Mobius: Mixture-Of-Experts Transformer Model in Epigenetics of ME/CFS and Long COVID

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Long COVID are chronic debilitating post-infectious illnesses that collectively affect up to 470 million individuals. Unlike illnesses of comparable scale, there are no validated blood or imaging tests for the clinical diagnosis of these conditions. Currently, these conditions are diagnosed through clinical exclusion, resulting in approximately 90% of ME/CFS patients being incorrectly diagnosed as Long COVID patients. This misdiagnosis contributes to delayed care and millions of dollars in healthcare burdens. We present Mobius, a transformer-based model that uses autoencoder-derived features from blood DNA methylation to distinguish ME/CFS, Long COVID, and healthy controls. Using 852 samples from 14 distinct datasets, our method employs three innovations: (i) self-supervised masked pretraining to learn epigenetic patterns, (ii) a sparsely-gated mixture-of-experts architecture to handle heterogeneous data, and (iii) an adaptive computation time mechanism for dynamic inference. Mobius achieved 97.06% accuracy (macro-F1 0.95, AUROC 0.96), outperforming current symptom-based diagnostics (58%) and baseline models such as XGBoost (82%). Ablation experiments showed that pretraining added 6% accuracy and that the gating and adaptive depth contributed an additional 7%. Our open-source pipeline could enable a much-needed objective blood test for these conditions and guide targeted precision medicine therapies.

genomics↗

bioRxiv2025

Glycan-reactive antibodies isolated from human HIV-1 vaccine trial participants show broad pathogen cross-reactivity

HIV-1 continues to pose a significant global health challenge, requiring ongoing research into effective prevention and treatment strategies. Understanding the B cell repertoire that can be engaged upon vaccination in humans is crucial for the development of future preventive vaccines. In this study, PBMCs from HIV-negative participants in the multivalent HVTN124 human HIV-1 vaccine clinical trial were interrogated for HIV-reactive B cells using LIBRA-seq, a high-throughput B cell mapping technology. We report the discovery of glycan-reactive antibodies capable of neutralizing diverse heterologous HIV-1 virus strains. Further, isolated antibodies showed broad cross-reactivity against antigens from a variety of other pathogens, while remaining mostly negative on autoreactivity assays. The emerging class of glycan- reactive virus-neutralizing antibodies with exceptional breadth of pathogen cross- reactivity may present an effective target for vaccination at the population level.

immunology↗

bioRxiv2025

Design of SARS-CoV-2 RBD Immunogens to Focus Immune Responses Towards Conserved Coronavirus Epitopes

SARS-CoV-2 continues to evolve, with new variants emerging that evade pre-existing immunity and limit the efficacy of existing vaccines. One approach towards developing superior, variant-proof vaccines is to engineer immunogens that preferentially elicit antibodies with broad cross-reactivity against SARS-CoV-2 and its variants by targeting conserved epitopes on spike. The inner and outer faces of the Receptor Binding Domain (RBD) are two such conserved regions targeted by antibodies that recognize diverse human and animal coronaviruses. To promote the elicitation of such antibodies by vaccination, we engineered "resurfaced" RBD immunogens that contained mutations at exposed RBD residues outside the target epitopes. In the context of pre-existing immunity, these vaccine candidates aim to disfavor the elicitation of strain-specific antibodies against the immunodominant Receptor Binding Motif (RBM) while boosting the induction of inner and outer face antibodies. The engineered resurfaced RBD immunogens were stable, lacked binding to monoclonal antibodies with limited breadth, and maintained strong interactions with target broadly neutralizing antibodies. When used as vaccines, they limited humoral responses against the RBM as intended. Multimerization on nanoparticles further increased the immunogenicity of the resurfaced RBDs immunogens, thus supporting resurfacing as a promising immunogen design approach to rationally shift natural immune responses to develop more protective vaccines.

immunology↗

bioRxiv2024

Structural and antigenic characterization of novel and diverse Henipavirus glycoproteins

Henipaviruses, a genus within the Paramyxoviridae family, include the highly virulent Nipah and Hendra viruses that cause reoccurring outbreaks of deadly disease. Recent discoveries of several new Paramyxoviridae species, including the zoonotic Langya virus, have revealed much higher antigenic diversity than currently characterized and prompted the reorganization of these viruses into the Henipavirus and Parahenipavirus genera. Here, to explore the limits of structural and antigenic variation in both genera, collectively referred to here as HNVs, we constructed an expanded, antigenically diverse panel of HNV fusion and attachment glycoproteins from 56 unique HNV strains that better reflects global HNV diversity. We expressed and purified the fusion protein ectodomains and the attachment protein head domains and studied their biochemical, biophysical and structural properties. We performed immunization experiments in mice leading to the elicitation of antibodies reactive to multiple HNV fusion proteins. Cryo-electron microscopy structures of diverse fusion proteins elucidated molecular determinants of differential pre-fusion state metastability and higher order contacts. A crystal structure of the Gamak virus attachment head domain revealed an additional domain appended to the conserved 6-bladed, {beta}-propeller fold. Taken together, these studies expand the known structural and antigenic limits of the HNVs, reveal new cross-reactive epitopes within both genera and provide foundational data for the development of broadly reactive countermeasures.

biochemistry↗

bioRxiv2024

Anti-HIV-1 B cell antigen receptor signaling and structure

The B cell antigen receptor (BCR) complex, comprised of antigen recognition and signaling components, functions in initiating B cell activation. While structural studies have described BCR domain organization, gaps remain in our understanding of its antigen binding domain (Fab, fragment antigen-binding) disposition, and how antigen binding is sensed to initiate signaling. Here, we report antigen affinity and signaling of the immunoglobulin (Ig) class IgM and IgG BCRs and define conformational states of full-length BCRs of two human broadly neutralizing antibodies, the glycan-specific, heavy chain domain-swapped, I-shaped 2G12, and a canonical Y-shaped antibody, CH31, that recognizes the CD4-binding site on the HIV-1 Envelope protein (Env). The BCRs adopted the shapes (I or Y) of their respective soluble antibodies, and both Ig class of BCRs of the same specificity bound Env trimers with similar affinities. We observed antigen-valenc y dependent differential signaling by the 2G12 IgM and IgG BCRs with trimeric Envs. Cryo-electron microscopy of the 2G12 IgG and CH31 IgM BCRs revealed varied Fab orientations. Structural comparisons revealed hinge points and regions of flexibility in the BCRs suggesting a highly dynamic structure of the BCR complex. Taken together, our results provide an integrated understanding of BCR structure, conformation, antigen recognition and signaling, and provide the basis for understanding antigen induced BCR signal transmission. One Sentence SummaryCryo-electron microscopy structures of full-length B cell antigen receptor complex provide a novel dynamic BCR model and a basis for understanding antigen binding induced signal transmission.

immunology↗

bioRxiv2024

HuR-dependent expression of RyR2 contributes to calcium-mediated thermogenesis in brown adipocytes

Several uncoupling protein 1 (UCP1)-independent thermogenic pathways have been described in thermogenic adipose tissue, including calcium-mediated thermogenesis in beige adipocytes via sarco/endoplasmic reticulum ATPase (SERCA). We have previously shown that adipocyte-specific deletion of the RNA binding protein human antigen R (HuR) results in thermogenic dysfunction independent of UCP1 expression. RNA sequencing revealed the downregulation of several genes involved in calcium ion transport upon HuR deletion. The goal of this work was to define the HuR-dependent mechanisms of calcium driven thermogenesis in brown adipocytes. We generated (BAT)-specific HuR-deletion (BAT-HuR-/-) mice and show that their body weight, glucose tolerance, brown and white adipose tissue weights, and total lipid droplet size were not significantly different compared to wild-type. Similar to our initial findings in Adipo-HuR-/- mice, mice with BAT-specific HuR deletion are cold intolerant following acute thermal challenge at 4{degrees}C, demonstrating specificity of acute HuR-dependent thermogenesis to BAT. We also found decreased expression of ryanodine receptor 2 (RyR2), but no changes in RyR2, SERCA1, SERCA2, or UCP1 expression, in BAT from BAT-HuR-/- mice. Next, we used Fluo-4 calcium indicator dye to show that genetic deletion or pharmacological inhibition of HuR blunts the increase in cytosolic calcium concentration in SVF-derived primary brown adipocytes. Moreover, we saw a similar blunting in {beta}-adrenergic-mediated heat generation, as assessed by ERtherm AC fluorescence, in SVF-derived brown adipocytes following HuR inhibition or deletion. Mechanistically, we show that HuR directly binds and reduces the decay rate of RyR2 mRNA in brown adipocytes, and stabilization of RyR2 via S107 rescues {beta}-adrenergic-mediated cytosolic calcium increase and heat generation in HuR deficient brown adipocytes. In conclusion, our results suggest that HuR-dependent control of RyR2 expression plays a significant role in the thermogenic function of brown adipose tissue through modulation of SR calcium cycling.

molecular biology↗