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Ford, M.

Publications and source records attributed to Ford, M..

17 recordsLinked to original sources

Isolation and characterisation of Lytic Jumbo Klebsiella phage BMPCR_005026

Background: Klebsiella pneumoniae is a key causative agent of multidrug resistant nosocomial infections. Bacteriophages offer a promising alternative treatment, but the diversity of Klebsiella species requires the characterisation of a broad range of phages, particularly the poorly characterised jumbo phages. Materials and Methods: Phage BMCPR_005026 was isolated from sewage against Klebsiella pneumoniae. Whole genome sequencing, transmission electron microscopy and host range analysis against a diverse set of 40 clinically relevant Klebsiella strains were used to characterise the phage. Results: The virion had a myovirus morphology and genomic analysis placed it within an undefined family in Caudoviricetes where it forms a new species within the genus Alcyoneusvirus. BMCPR_005026 could form plaques on 3 of the 40 Klebsiella strains tested (7.5%) and formed halos. Conclusion: BMCPR_005026 represents a new species of phage within the genus Alcyoneusvirus with activity against 3 Klebsiella KL-types.

microbiology↗

First detected incursions of avian influenza H5N1 clade 2.3.4.4b into mainland Australia from the Southern Ocean

High pathogenicity avian influenza H5N1 clade 2.3.4.4b has caused a panzootic of devastating impact to poultry and wildlife globally. The Australian continent and broader Oceania until recently remained the last major region without confirmed detections. Here we report the first H5N1 clade 2.3.4.4b detections from two live seabirds - a brown skua and a southern giant petrel - found on the south coast of Western Australia in June 2026. Virus genome sequencing showed that both viruses were most closely related to H5N1 viruses detected recently on sub-Antarctic islands in the Southern Indian Ocean. In time-calibrated phylogeographic analyses, both viruses sampled in Western Australia clustered with viruses from Heard Island, a sub-Antarctic external territory of Australia. Ancestral location reconstruction also identified Heard Island as the most probable source location, although unsampled intermediate locations cannot be excluded. The two Western Australian detections were estimated to be independent incursions from Heard Island, rather than local transmission on mainland Australia. There was no evidence of reassortment with endemic avian influenza viruses in Australia, and both virus sequences retained key avian-like genetic markers and lacked known substitutions for reduced antiviral susceptibility. These detections revealed a Southern Ocean pathway of recurrent H5N1 incursions into Australia, highlighting the risk of potential establishment on the mainland and the need for heightened surveillance and rapid, nationally-coordinated, virus genomic characterisation.

microbiology↗

Cannabis Use by People with HIV is Associated with an Anti-Inflammatory Immunometabolic Phenotype in Monocyte-Derived Macrophages

Chronic neuroinflammation is associated with comorbidities in people with HIV (PWH) on antiretroviral therapy (ART). While cannabis use is associated with reduced neuroinflammation and neurocognitive impairment (NCI) in PWH, the underlying mechanisms are unknown. To address this gap in knowledge, we analyzed monocyte-derived macrophages (MDMs) from a cohort of 50 PWH and 33 people without HIV (mean age: 61.9 years), categorized by frequency of cannabis use (naive/low, moderate, daily). We performed immunocytochemistry, RNA sequencing, and qPCR on MDMs and quantified related biomarkers in donor plasma. In this cohort study, daily cannabis use in PWH was associated with less global neurocognitive deficits, and with an anti-inflammatory immunometabolic-phenotype in MDMs characterized by (1) a metabolic shift from glycolysis to oxidative phosphorylation, (2) higher mitochondrial numbers, (3) altered cytokine profiles (pro-inflammatory downregulation, anti-inflammatory upregulation), and (4) higher brain-derived neurotrophic factor (BDNF) expression. These cellular changes were corroborated by a plasma biomarker profile in PWH including (1) lower levels of growth differentiation factor 15 and soluble triggering receptor expressed on myeloid cells 2, and (2) higher mature BDNF/precursor BDNF ratios that correlated with better cognition. Thus, cannabis use may mitigate NCI in PWH by immunometabolically reprogramming MDM function towards an anti-inflammatory and neuroprotective state. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=140 SRC="FIGDIR/small/709579v1_ufig1.gif" ALT="Figure 1"> View larger version (42K): org.highwire.dtl.DTLVardef@15fb1adorg.highwire.dtl.DTLVardef@189d79corg.highwire.dtl.DTLVardef@aa6a89org.highwire.dtl.DTLVardef@3852f8_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

MYC and Epithelial to Mesenchymal Transition (EMT) Independently Predict Circadian Rhythm Disruption in Lung Adenocarcinoma

The molecular circadian clock is known to be disrupted in lung adenocarcinoma, and its disruption is pro-tumorigenic in mouse models of this disease. However, the determinants of disruption of the molecular clock in human cancer are not clear. We hypothesized that derangement in expression of specific circadian clock genes or elevated MYC expression could correlate with circadian disruption in human tumors, and used Clock Correlation Distance (CCD) to compare clock order and strength in tumors based on the expression of these genes. While the expression of individual circadian genes did not consistently correlate with disruption, tumors with the highest expression of MYC or high MYC pathway activation had significantly disrupted rhythms compared to those with lower MYC. Unexpectedly, a subset of tumors with very low levels of MYC, below that found in normal lung, also showed disruption of circadian rhythms, prompting us to explore novel determinants of disruption in these tumors. We found that expression of programs associated with epithelial to mesenchymal Transition (EMT) and TGF-{beta} signaling were enriched in tumors with the lowest MYC expression, and that, surprisingly, those tumors with a mesenchymal expression pattern had more ordered (stronger) rhythms. To directly test this correlation between cell state and rhythms, we exposed lung adenocarcinoma cells to TGF-{beta} to induce EMT. TGF-{beta} induced a quasi-mesenchymal phenotype and caused a significant increase in the amplitude of oscillations in these cells. Together, our data show that MYC expression, pathway activation, and a mesenchymal cell state are both independent determinants of circadian status in lung adenocarcinoma.

cancer biology↗

Functional immune profiling reveals CD4+ T cell dysregulation associated with celiac disease

T cells integrate signals from antigen and co-stimulatory receptors to calibrate the strength and quality of their responses. This signal integration is influenced by genetic background, which can modulate thresholds for immune tolerance and strength of responses to threat. Celiac disease (CeD) is an autoimmune disorder driven by well-defined genetic risk and characterised by immune dysregulation in response to dietary gluten. However, whether sensitivity or response differences in naive T cell programming contributes to disease susceptibility is not known. To investigate such variation, we developed a sensitive quantitative platform, the momentum assay, which combines standardised, T cell activation with subsequent stimulus withdrawal, enabling measurement of T cell proliferation and survival over time. This assay is integrated with the Cyton2 mathematical model to infer underlying cellular timer programs from population-level dynamics. We applied this method to assess whether naive T cells from individuals with celiac disease (CeD) exhibited altered responses compared to healthy donors (HDs). We found that CD4+ but not CD8+ T cells from CeD patients showed a hypo-proliferative response following stimulation, associated with impaired secretion of the proliferative and pro-survival cytokine IL-2. Moreover, surface expression of early activation marker, CD69 remained elevated for longer on CD4+ T cells from CeD donors after stimulus withdrawal, suggesting prolonged activation and subtle alterations in regulatory feedback mechanisms. These findings reveal previously unrecognised quantitative alterations in naive T cell programming in CeD and underscore the utility of model-based analytical frameworks for detecting subtle functional perturbations in complex immune-mediated diseases.

immunology↗

VARP binds SNX27 to promote endosomal supercomplex formation on membranes

Multiple essential membrane trafficking pathways converge at endosomes to maintain cellular homeostasis by sorting critical transmembrane cargo proteins to the plasma membrane or the trans-Golgi network (TGN). The Retromer heterotrimer (VPS26/VPS35/VPS29 subunits) binds multiple sorting nexin (SNX) proteins on endosomal membranes, but molecular mechanisms regarding formation and regulation of metazoan SNX/Retromer complexes have been elusive. Here, we combine biochemical and biophysical approaches with AlphaFold2 Multimer modeling to identify a direct interaction between the VARP N-terminus and SNX27 PDZ domain. VARP and SNX27 interact with high nanomolar affinity using the binding pocket established for PDZ binding motif (PDZbm) cargo. Specific point mutations in VARP abrogate the interaction in vitro. We further establish a full biochemical reconstitution system using purified mammalian proteins to directly and systematically test whether multiple endosomal coat complexes are recruited to membranes to generate tubules. We successfully use purified coat components to demonstrate which combinations of Retromer with SNX27, ESCPE-1 (SNX2/SNX6), or both complexes can remodel membranes containing physiological cargo motifs and phospholipid composition. SNX27, alone and with Retromer, induces tubule formation in the presence of PI(3)P and PDZ cargo motifs. ESCPE-1 deforms membranes enriched with Folch I and CI-MPR cargo motifs, but surprisingly does not recruit Retromer. Finally, we find VARP is required to reconstitute a proposed endosomal "supercomplex" containing SNX27, ESCPE-1, and Retromer on PI(3)P-enriched membranes. These data suggest VARP functions as a key regulator in metazoans to promote cargo sorting out of endosomes.

biochemistry↗

Contrasting dynamics of two incursions of low pathogenicity avian influenza virus into Australia

The current panzootic of high pathogenicity avian influenza virus H5N1 demonstrates how viral incursions can have major ramifications for wildlife and domestic animals. Herein, we describe the recent incursion into Australia of two low pathogenicity avian influenza virus subtypes, H4 and H10, that exhibited contrasting evolutionary dynamics. Viruses detected from national surveillance and disease investigations between 2020-2022 revealed 27 genomes, 24 of which have at least one segment more closely related to Eurasian or North American avian influenza lineages than those already circulating in Australia. Phylogenetic analysis revealed that H4 viruses circulating in shorebirds represent a recent incursion from Asia that is distinct from those circulating concurrently in Australian waterfowl. Analysis of the internal segments further demonstrates exclusive, persistent circulation in shorebirds. This contrasts with H10, where a novel lineage has emerged in wild waterfowl, poultry and captive birds across Australia, and has likely replaced previously circulating H10 lineages through competitive exclusion. Elucidating different dynamics for avian influenza incursions supports effective disease risk identification and communication that better informs disease preparedness and response.

microbiology↗

Breaking free from the clocks tyranny restores memory to brain damaged flies

The relationship between sleep and memory is an active topic of investigation. In this context, we demonstrate that enhancing sleep restores memory to flies with ablated Mushroom Bodies (MB), a key memory center; this is consistent across several memory assays. Mapping the underlying circuitry reveals circadian modulation of a subset of Dopaminergic neurons (DANs) that modulate aversive learning. Using imaging, we show that MB-ablation disrupts, and sleep restores the time of day these neurons are most responsive. Knocking down the receptor for the clock output signal, Pigment-dispersing factor (Pdfr), in this subset of DANs restores memory to MB-ablated flies. Crucially, MB-ablation does not result in memory impairments in the absence of a functioning clock. Our results reveal neuromodulations key role in cognitive restoration, where sleep aids memory in damaged brains, but a functioning clock unexpectedly hinders this process.

neuroscience↗

An adaptive biomolecular condensation response is conserved across environmentally divergent species

Cells must sense and respond to sudden maladaptive environmental changes--stresses--to survive and thrive. Across eukaryotes, stresses such as heat shock trigger conserved responses: growth arrest, a specific transcriptional response, and biomolecular condensation of protein and mRNA into structures known as stress granules under severe stress. The composition, formation mechanism, adaptive significance, and even evolutionary conservation of these condensed structures remain enigmatic. Here we provide an unprecedented view into stress-triggered condensation, its evolutionary conservation and tuning, and its integration into other well-studied aspects of the stress response. Using three morphologically near-identical budding yeast species adapted to different thermal environments and diverged by up to 100 million years, we show that proteome-scale biomolecular condensation is tuned to species-specific thermal niches, closely tracking corresponding growth and transcriptional responses. In each species, poly(A)-binding protein--a core marker of stress granules--condenses in isolation at species-specific temperatures, with conserved molecular features and conformational changes modulating condensation. From the ecological to the molecular scale, our results reveal previously unappreciated levels of evolutionary selection in the eukaryotic stress response, while establishing a rich, tractable system for further inquiry.

cell biology↗

Preparing future STEM faculty nationwide through flexible teaching professional development

We report on a five-year initiative that has prepared thousands of future STEM faculty around the world to adopt evidence-based instructional practices by participating in two massive open online courses (MOOCs) and facilitated in-person learning communities. This novel combination of asynchronous online and coordinated, structured face-to-face learning community experiences provides flexible options for STEM graduate students and postdoctoral fellows to pursue teaching professional development, while leveraging the affordances of educational technologies and the geographically clustered nature of this target learner demographic. A total of 14,977 participants enrolled in seven offerings of the introductory course held 2014-2018, with 1,725 participants from approximately 60 countries completing at an average course completion rate of 13%. The preparation of future STEM faculty makes an important difference in establishing high-quality instruction that meets the diverse needs of all undergraduate students, and the initiative described here can serve as a model for increasing access to such preparation.

scientific communication and education↗

ImmunoTyper-SR: A Novel Computational Approach for Genotyping Immunoglobulin Heavy Chain Variable Genes using Short Read Data

Human immunoglobulin heavy chain (IGH) locus on chromosome 14 includes more than 40 functional copies of the variable gene (IGHV), which, together with the joining genes (IGHJ), diversity genes (IGHD), constant genes (IGHC) and immunoglobulin light chains, code for antibodies that identify and neutralize pathogenic invaders as a part of the adaptive immune system. Because of its highly repetitive sequence composition, the IGH locus has been particularly difficult to assemble or genotype through the use of standard short read sequencing technologies. Here we introduce ImmunoTyper-SR, an algorithmic method for genotype and CNV analysis of the germline IGHV genes using Illumina whole genome sequencing (WGS) data. ImmunoTyper-SR is based on a novel combinatorial optimization formulation that aims to minimize the total edit distance between reads and their assigned IGHV alleles from a given database, with constraints on the number and distribution of reads across each called allele. We have validated ImmunoTyper-SR on 12 individuals with Illumina WGS data from the 1000 Genomes Project, whose IGHV allele composition have been studied extensively through the use of long read and targeted sequencing platforms, as well as nine individuals from the NIAID COVID Consortium who have been subjected to WGS twice. We have then applied ImmunoTyper-SR on 585 samples from the NIAID COVID Consortium to investigate associations between distinct IGHV alleles and anti-type I IFN autoantibodies which have been linked to COVID-19 severity.

bioinformatics↗

Increased mitochondrial activity upon CatSper channel activation is required for sperm capacitation.

To fertilize an oocyte, sperm must become hyperactive. However, whether they obtain ATP for hyperactivated motility via glycolysis or mitochondrial respiration is unclear. Here, high-resolution respirometry, flow cytometry, and confocal microscopy experiments revealed that mitochondrial respiration and membrane potential increased during mouse sperm capacitation. Treatment with inhibitors of mitochondrial respiration prevented sperm from hyperactivating and fertilizing an oocyte. Mitochondrial respiration was impaired in sperm from mice lacking the calcium channel CatSper. We developed a method to image mitochondrial calcium in sperm and found that CatSper activation led to increased mitochondrial calcium concentration. Finally, treating sperm with an inhibitor of mitochondrial calcium import impaired mitochondrial function and sperm hyperactivation. Together, our results uncover a new role of sperm mitochondria and reveal a new pathway connecting calcium influx through CatSper to mitochondrial activity and the sperm hyperactivation required to fertilize an oocyte. SummaryThe source of ATP for sperm hyperactivation is unclear. Ferreira et al. show that mitochondrial activity increases during, and is required for, hyperactivation and fertilization ability. Increased mitochondrial activity depends on calcium influx through the channel CatSper.

cell biology↗

From COVID-19 to the Common Cold: Novel Host-Targeted, Pan-Respiratory Antiviral Small Molecule Therapeutics

We present a novel small molecule antiviral chemotype that was identified by an unconventional cell-free protein synthesis and assembly-based phenotypic screen for modulation of viral capsid assembly. Activity of PAV-431, a representative compound from the series, has been validated against infectious virus in multiple cell culture models for all six families of viruses causing most respiratory disease in humans. In animals this chemotype has been demonstrated efficacious for Porcine Epidemic Diarrhea Virus (a coronavirus) and Respiratory Syncytial Virus (a paramyxovirus). PAV-431 is shown to bind to the protein 14-3-3, a known allosteric modulator. However, it only appears to target the small subset of 14-3-3 which is present in a dynamic multi-protein complex whose components include proteins implicated in viral lifecycles and in innate immunity. The composition of this target multi-protein complex appears to be modified upon viral infection and largely restored by PAV-431 treatment. Our findings suggest a new paradigm for understanding, and drugging, the host-virus interface, which leads to a new clinical therapeutic strategy for treatment of respiratory viral disease.

biochemistry↗

Extracellular vesicles from retinal pigment epithelial cells expressing R345W-Fibulin-3 induce epithelial-mesenchymal transition in recipient cells.

PurposePrevious studies in our lab found that expression of R345W-Fibulin-3 induces retinal pigment epithelial (RPE) cells to undergo epithelial-mesenchymal transition (EMT). The purpose of the current study was to investigate the size, cargo and function of extracellular vesicles (EVs) derived from RPE cells expressing wild-type (WT)-Fibulin-3 compared to RPE cells expressing the R345W-Fibulin-3 mutation, and to determine the role of these EVs in regulating RPE cell dysfunction. MethodsARPE-19 cells were infected with luciferase-tagged wild-type Fibulin-3 (WT)- or luciferase-tagged R345W-Fibulin-3 (mutant) using lentivirus. EVs were isolated from the media of ARPE-19 cells by conventional ultracentrifugation or density gradient ultracentrifugation. Transmission electron microscopy (TEM) and cryogenic electron microscopy (cryo-EM) were performed to study the morphology of the EVs. The amount and size distribution of EVs were determined by Nanoparticle Tracking Analysis (NTA). EV protein concentrations were quantified using the DCTM Protein Assay (Bio-Rad). EV cargo were analyzed by unbiased proteomics using LC-MS/MS with subsequent pathway analysis (Advaita). The EV-associated transforming growth factor beta 1 (TGF-{beta}1) protein was measured by Enzyme-linked immunosorbent assay (ELISA). The EV transplant study was conducted and migration ability was evaluated in ARPE-19 cells with or without exposure to EVs by conducting scratch assays. ResultsTEM imaging revealed concave-appearing vesicles, and cryo-EM imaging showed spherical vesicles with two subpopulations of EVs: a small group with diameters around 30nm and a large group with diameters around 100nm. Imaging also indicated a greater number of small EVs (~30 nm) in the mutant group compared to the WT group. This result was further confirmed by NTA showing that, in the mutant group, the particle size distributions were smaller than those of the WT EVs. There were no significant differences in EV protein concentrations per EV between WT and mutant groups. Proteomic studies showed that EVs derived from ARPE-19 cells expressing WT-Fibulin-3 contain critical members of sonic hedgehog signaling (SHH) signaling and ciliary tip components, whereas EVs derived from RPE cells expressing R345W-Fibulin-3 contain EMT mediators, including TGF-{beta}-induced protein (TGFBI), vimentin, and mothers against decapentaplegic homolog 4 (SMAD4), indicating that the EV cargo reflects the phenotypic status of their parental cells. Subsequent studies revealed enhanced activity of TGF-{beta}1 associated with mutant EVs compared to WT EVs. Critically, EV transplant studies showed that treatment of recipient RPE cells with mutant RPE cell-derived EVs was sufficient to induce an enhanced migration ability and elevated EMT marker expression of RPE cells. ConclusionsThe expression of R345W-Fibulin-3 alters the size, cargo and autocrine function of EVs. Notably, EVs derived from RPE cells expressing R345W-Fibulin-3 are sufficient to induce EMT in uninfected RPE cells.

cell biology↗

High Throughput Computational Mouse Genetic Analysis

BackgroundGenetic factors affecting multiple biomedical traits in mice have been identified when GWAS data that measured responses in panels of inbred mouse strains was analyzed using haplotype-based computational genetic mapping (HBCGM). Although this method was previously used to analyze one dataset at a time; but now, a vast amount of mouse phenotypic data is now publicly available, which could lead to many more genetic discoveries. ResultsHBCGM and a whole genome SNP map covering 53 inbred strains was used to analyze 8462 publicly available datasets of biomedical responses (1.52M individual datapoints) measured in panels of inbred mouse strains. As proof of concept, causative genetic factors affecting susceptibility for eye, metabolic and infectious diseases were identified when structured automated methods were used to analyze the output. One analysis identified a novel genetic effector mechanism; allelic differences within the mitochondrial targeting sequence affected the subcellular localization of a protein. We also found allelic differences within the mitochondrial targeting sequences of many murine and human proteins, and these could affect a wide range of biomedical phenotypes. ImplicationsThese initial results indicate that genetic factors affecting biomedical responses could be identified through analysis of very large datasets, and they provide an early indication of how this type of augmented intelligence can facilitate genetic discovery.

bioinformatics↗

A Methodological Assessment and Characterization of Genetically-Driven Variation in Three Human Phosphoproteomes

Phosphorylation of proteins on serine, threonine, and tyrosine residues is a ubiquitous post-translational modification that plays a key part of essentially every cell signaling process. It is reasonable to assume that inter-individual variation in protein phosphorylation may underlie phenotypic differences, as has been observed for practically any other molecular regulatory phenotype. However, we do not know much about the extent of inter-individual variation in phosphorylation because it is quite challenging to perform a quantitative high throughput study to assess inter-individual variation in any post-translational modification. To test our ability to address this challenge with current technology, we quantified phosphorylation levels for three genotyped human cell lines within a nested experimental framework, and found that genetic background is the primary determinant of phosphoproteome variation. We uncovered multiple functional, biophysical, and genetic associations with germline driven phosphopeptide variation. Variants affecting protein levels or structure were among these associations, with the latter presenting, on average, a stronger effect. Interestingly, we found evidence that is consistent with a phosphopeptide variability buffering effect endowed from properties enriched within longer proteins. Because the small sample size in this pilot study may limit the applicability of our genetic observations, we also undertook a thorough technical assessment of our experimental workflow to aid further efforts. Taken together, these results provide the foundation for future work to characterize inter-individual variation in post-translational modification levels and reveal novel insights into the nature of inter-individual variation in phosphorylation.

genomics↗

Sexually divergent DNA methylation programs with hippocampal aging

DNA methylation is a central regulator of genome function and altered methylation patterns are indicative of biological aging and mortality. Age-related cellular, biochemical, and molecular changes in the hippocampus lead to cognitive impairments and greater vulnerability to neurodegenerative disease that varies between the sexes. The role of hippocampal epigenomic changes with aging in these processes is unknown as no genome-wide analyses of age-related methylation changes have considered the factor of sex in a controlled animal model. High-depth, genome-wide bisulfite sequencing of young (3 month) and old (24 month) male and female mouse hippocampus revealed that while total genomic methylation amounts did not change with aging, specific sites in CG and non-CG (CH) contexts demonstrated age-related increases or decreases in methylation that were predominantly sexually divergent. Differential methylation with age for both CG and CH sites was enriched in intergenic, and intronic regions and under-represented in promoters, CG islands and specific enhancer regions in both sexes suggesting that certain genomic elements are especially labile with aging, even if the exact genomic loci altered are predominantly sex-specific. Life-long sex differences in autosomal methylation at CG and CH sites were also observed. The lack of genome-wide hypomethylation, sexually divergent aging response, and autosomal sex differences at CG sites were confirmed in human data. These data reveal sex as a previously unappreciated central factor of hippocampal epigenomic changes with aging. In total, these data demonstrate an intricate regulation of DNA methylation with aging by sex, cytosine context, genomic location, and methylation level.

neuroscience↗