Biology subjects

Ussher, J.

Publications and source records attributed to Ussher, J..

5 recordsLinked to original sources

bioRxiv2026

Pharmacologic Targeting of ZNF281 Suppresses Metastatic Prostate Cancer Beyond Androgen Receptor Dependence

Metastatic prostate cancer remains a lethal disease, with most treatments focusing on the androgen receptor (AR) axis. We identified the zinc finger protein 281 (ZNF281) as a previously unrecognized driver of metastatic prostate cancer that promotes both AR-related transcriptional output and distinct AR-independent tumor-promoting pathways. It increases AR expression and acts as a coactivator to promote AR transcriptional activity. Independent of AR, ZNF281 promotes prostate cancer by upregulating SMURF1 to sustain tumor growth and by promoting SNAIL-mediated metastasis. We developed an orally bioavailable, ZNF281 Interfering Molecule (Oral ZIM) that disrupts its DNA binding and AR protein interaction. Knockout of ZNF281 as well as treatment with oral ZIM potently inhibited prostate cancer growth and metastasis in orthotopic xenograft models of castration-sensitive and castration-resistant prostate cancers (without detectable systemic toxicity), and ZIM outperformed enzalutamide treatment in patient-derived prostate cancer organoids.

cancer biology↗

bioRxiv2026

Mitochondrial-targeted therapy with elamipretide preserves cardiac function and prevents late mortality in murine sepsis-induced cardiac dysfunction.

Sepsis-induced cardiac dysfunction (SICD) occurs in nearly half of septic patients, is associated with increased mortality, and lacks targeted therapy. Emerging evidence implicates impaired mitochondrial function and metabolic inflexibility as central contributors to myocardial depression. Here, we characterized SICD in a murine model of polymicrobial sepsis and evaluated the therapeutic potential of the cardiolipin-stabilizing peptide elamipretide (Ela). Sepsis induced marked impairments in cardiac performance, accompanied by reductions in cardiac cardiolipin content, impaired mitochondrial respiratory capacity localized to complex I, and altered substrate utilization. Integration of stable isotope metabolic flux tracing with lipidomic, metabolomic, and proteomic analyses identified a convergent metabolic bottleneck at the level of the electron transport system. This defect was associated with upstream accumulation of acetyl-CoA, Co-A esters, and ketone bodies, consistent with impaired oxidative flux and energetic failure. Administration of a single early dose of Ela restored cardiolipin content, complex I function, normalized metabolic flux, improved cardiac function during both acute sepsis and recovery, and completely prevented late sepsis-related mortality. These findings identify cardiolipin-dependent mitochondrial dysfunction as a central pathogenic mechanism underlying SICD and position mitochondrial-targeted therapy as a promising therapeutic strategy in sepsis. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=130 SRC="FIGDIR/small/736409v1_ufig1.gif" ALT="Figure 1"> View larger version (47K): org.highwire.dtl.DTLVardef@1ca5b47org.highwire.dtl.DTLVardef@2ecfc2org.highwire.dtl.DTLVardef@149ccb9org.highwire.dtl.DTLVardef@1fbcb6_HPS_FORMAT_FIGEXP M_FIG C_FIG Ela improves SICD by stabilizing cardiolipin species and improving mitochondrial complex I function. SICD depicted in red denotes conditions altered compared to healthy control cardiomyocyte, SICD+Ela depicted in green denotes changes relative to SICD. SICD, sepsis-induced cardiac dysfunction; ELA, elamipretide; ADP, adenosine diphosphate; ATP, adenosine triphosphate; ROS, reactive oxygen species.

physiology↗

bioRxiv2026

Rapid GeneXpert surveillance of influenza A virus in seabirds and the environment provides early warning for wildlife health in Aotearoa New Zealand

The global expansion of highly pathogenic avian influenza (HPAI) virus A(H5N1) underscores the need for rapid surveillance at high-risk wildlife interfaces. Taiaroa Head (45.7828{degrees} S, 170.7333{degrees} E) in the South Island of Aotearoa New Zealand hosts a plethora of aquatic wildlife including a large red-billed gull (Chroicocephalus novaehollandiae scopulinus) colony as well as the only mainland breeding colony of northern royal albatross (Diomedea sanfordi). The Royal Albatross Centre is also a major nature tourism destination, attracting tens of thousands of visitors annually, thereby creating a dense ecological and human-wildlife interface vulnerable to viral incursion. We evaluated the GeneXpert II platform using the Xpert(R) Xpress Flu/RSV cartridge as a field-deployable tool for avian influenza virus detection in environmental and wildlife-associated samples. The assay detected synthetic influenza A viral RNA and multiple endemic low pathogenic avian influenza virus subtypes (A(H3N8), A(H1N9), A(H5N2) and A(H7N7)) circulating in New Zealand birds. Influenza A virus was reliably identified in spiked environmental water samples with no consistent PCR inhibition as well as naturally occurring avian influenza virus in duck pond water. Field deployment demonstrated that the system could be operated by non-laboratory personnel with minimal training in a non-clinical setting. This study establishes the feasibility of near-real-time environmental monitoring. Repurposing clinical cartridge-based point-of-care diagnostics offers a practical early warning approach for avian influenza virus surveillance at ecologically and economically significant locations.

microbiology↗

bioRxiv2026

An inducer of snail hibernation causes quiescence and hibernation-like cardioprotection, through metabolic rewiring and autophagy, in mice hearts

Cells of hibernators achieve dormancy, resembling cellular quiescence, through molecular rewiring, metabolic remodelling and autophagy, resisting ischemic and ischemia-reperfusion (IR) injury, while non-hibernators are vulnerable to both. We discovered a circulating dormancy-inducing factor in hibernating snails, synthesized it chemically and because it activates PHLPP1 (a phosphatase regulating the mTOR mediators p-AKT and p-S6K1), named it SNail Activator of PHLPP1 (SNAP). During IR, plasma membrane PHLPP1 and p-AKT translocate to the cytoplasm and mitochondria. SNAP dephosphorylates mitochondrial p-AKT, p-S6K1 and induces dormancy in snails and quiescence (autophagy, reversible cell-cycle exit, proteostasis, apoptosis-resistance) in ischemic mouse fibroblasts. In IR models of cardiomyocytes and perfused hearts, SNAP is cardioprotective by preserving Pyruvate Dehydrogenase (PDH) activity, preventing mitochondrial depolarization, apoptosis and ROS-induced ER stress. SNAPs cardioprotective and mitochondrial effects are absent in hearts with a cardiomyocyte-specific PDH knockout. SNAP reveals fundamental mechanisms of quiescence under stress; while its cardioprotection may be beneficial in the IR injury of normal hearts offered for transplantation, a major challenge in transplant medicine.

cell biology↗

bioRxiv2024

Immune correlates of early clearance of Mycobacterium tuberculosis among tuberculosis household contacts in Indonesia

Some individuals, even when heavily exposed to an infectious tuberculosis patient, do not develop a specific T-cell response as measured by interferon-gamma release assay (IGRA). This could be explained by an IFN-{gamma}-independent adaptive immune response, or an effective innate host response clearing Mycobacterium tuberculosis (Mtb) without adaptive immunity. In heavily exposed Indonesian tuberculosis household contacts (n=1347), a persistently IGRA negative status was associated with presence of a BCG scar, and - especially among BCG-vaccinated individuals - with altered innate immune cells dynamics, higher heterologous (Escherichia coli-induced) proinflammatory cytokine production, and higher inflammatory proteins in the IGRA mitogen tube. Neither circulating concentrations of Mtb-specific antibodies nor functional antibody activity associated with IGRA status at baseline or follow-up. In a cohort of adults in a low tuberculosis incidence setting, BCG vaccination induced heterologous innate cytokine production, but only marginally affected Mtb-specific antibody profiles. Our findings suggest that a more efficient host innate immune response, rather than a humoral response, mediates early clearance of Mtb. The protective effect of BCG vaccination against Mtb infection may be linked to innate immune priming, also termed trained immunity.

immunology↗