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Rutter, M.

Publications and source records attributed to Rutter, M..

4 recordsLinked to original sources

Microbial, dietary insect, and pathogen communities in fresh and decomposing guano of anthropic little brown bat (Myotis lucifugus) maternity colonies

The guano of insectivorous bats holds ecological information that can be assessed non-invasively to characterize the gut microbiome and diet, alongside environmental microbes and pathogens of conservation concern. Despite this potential, how guano communities change during decomposition remains understudied, particularly inside anthropic roosts rather than caves. In this study, guano from little brown bat (Myotis lucifugus) colonies was sampled monthly across the summer maternity season from three sites across two locations in Connecticut, USA, at fresh deposition and at 4, 8, and 12 weeks following deposition. Resolving these cross-kingdom signals required five workflows: short-read 16S and ITS2 amplicon sequencing (Illumina) for bacterial and fungal profiling, long-read CO1 metabarcoding (Oxford Nanopore) for arthropod diet in fresh samples, long-read shotgun metagenomics for viral identification in aged samples, and targeted qPCR for organisms of bat, human, and forest-health concern. Fresh guano generated a consistent bacterial signal across sites, whereas fresh fungal communities differed by site. Responses to decomposition depended on roost setting: exterior sites lost fungal diversity and shifted toward environmental aerobes over time, while the interior roost retained the fresh sample profile. Dietary composition varied temporally, was dominated by Diptera, and included the invasive emerald ash borer (Agrilus planipennis). Pseudogymnoascus destructans, the causal agent of white-nose syndrome, occurred in fresh and aged samples at all three sites but persisted for 12 weeks only at the interior roost, where antifungal bacterial taxa were depleted. Long-read shotgun metagenomics of aged guano recovered roughly 100 viral species, predominantly bacteriophages, alongside non-bacteriophage mastadenoviruses associated with humans, bats, and other mammals. These results show that anthropic structures influence the trajectory of guano microbiome succession, and that maternity colony guano enables non-invasive assessment of environmental pathogens, bat diet, and bacterial and fungal communities.

ecology↗

Mink by mink: stitching together signatures of subspecies adaptation through a pangenome of threatened mustelids

The American mink (Neogale vison), a semi-aquatic Mustelidae carnivoran with broad ecological range across North America, includes several putative subspecies of conservation concern. To investigate the evolutionary history and adaptive signatures of mink subspecies, chromosome-scale genome assemblies were generated for six individuals representing three southern subspecies: N. vison evergladensis, N. vison vulgivaga, and N. vison lutensis. Genomes were assembled using Illumina short reads, scaffolded with Oxford Nanopore long reads, and aligned to the phased N. vison reference genome. Assemblies ranged from 75.9% to 97.8% completeness, with five meeting thresholds for pangenome construction. A reference-free pangenome revealed an open architecture, highlighting considerable subspecies diversity. Subspecies-specific gene enrichment reflected adaptation: N. vison evergladensis showed enrichment in traits related to reproduction and sensory function; N. vison vulgivaga in cytoskeletal remodeling and oxidative stress; and N. vison lutensis in neuronal development, synaptic plasticity and cellular stress pathways. Assessment of the mitogenomes resolved N. vison lutensis as a distinct lineage, while nuclear data supported broader subspecies divergence but lacked fine scale resolution. N. vison evergladensis showed multiple signatures of small population size, including inbreeding coefficients (FROH) above 0.5, and displayed consistent population decline over time via demographic inference. Our findings support evergladensis as a distinct subspecies, supported by both the mitogenome phylogeny, and significant functional differentiation. As the first pangenome for Mustelidae, this study demonstrates the power of integrating cross-platform sequencing with natural history specimens to improve the resolution on signatures of adaptation and inform conservation policy and management of threatened populations.

genomics↗

Computational design of highly signaling active membrane receptors through de novo solvent-mediated allosteric networks

Protein catalysis and allostery require the atomic-level orchestration and motion of residues, ligand, solvent and protein effector molecules, but the ability to design protein activity through precise protein-solvent cooperative interactions has not been demonstrated. Here, we report the design of a dozen novel membrane receptors catalyzing G-protein nucleotide exchange through diverse de novo engineered allosteric pathways mediated by cooperative networks of intra-protein, protein-ligand and solvent molecule interactions. Consistent with the predictions, designed protein activities strongly correlated with the level of solvent-mediated interaction network plasticity at flexible transmembrane helical interfaces. Several designs displayed considerably enhanced thermostability and activity compared to related natural receptors. The most stable and active variant crystallized in an unforeseen signaling active conformation, in excellent agreement with the design models. The allosteric network topologies of the best designs bear limited similarity to those of natural receptors and reveal a space of allosteric interactions larger than previously inferred from natural proteins. The approach should prove useful for engineering proteins with novel complex protein catalytic and signaling activities.

biophysics↗

Investigating causal relationships between sleep traits and risk of breast cancer: a Mendelian randomization study

ObjectiveTo examine whether sleep traits have a causal effect on risk of breast cancer.\n\nDesignMultivariable regression, one- and two-sample Mendelian randomization.\n\nSettingThe UK Biobank prospective cohort study and the Breast Cancer Association Consortium (BCAC) case-control genome-wide association study.\n\nParticipants156,848 women in the multivariable regression and one-sample Mendelian randomization analysis in UK Biobank (7,784 with a breast cancer diagnosis) and 122,977 breast cancer cases and 105,974 controls from BCAC in the two-sample Mendelian randomization analysis.\n\nExposuresSelf-reported chronotype (morning/evening preference), insomnia symptoms and sleep duration in multivariable regression, and genetic variants robustly associated with these sleep traits.\n\nMain outcome measuresBreast cancer (prevalent and incident cases in UK Biobank, prevalent cases only in BCAC).\n\nResultsIn multivariable regression analysis using data on breast cancer incidence in UK Biobank, morning preference was inversely associated with breast cancer (HR 0.95, 95% CI 0.93, 0.98 per category increase) while there was little evidence for an association with sleep duration and insomnia symptoms. Using 341 single nucleotide polymorphisms (SNPs) associated with chronotype, 91 SNPs associated sleep duration and 57 SNPs associated with insomnia symptoms, one-sample MR analysis in UK Biobank provided some supportive evidence for a protective effect of morning preference on breast cancer risk (HR 0.85, 95% 0.70, 1.03 per category increase) but imprecise estimates for sleep duration and insomnia symptoms. Two-sample MR using data from BCAC supported findings for a protective effect of morning preference (OR 0.88, 95% CI 0.82, 0.93 per category increase) and adverse effect of increased sleep duration (OR 1.19, 95% CI 1.02, 1.39 per hour increase) on breast cancer (both estrogen receptor positive and negative), while there was inconsistent evidence for insomnia symptoms. Results were largely robust to sensitivity analyses accounting for horizontal pleiotropy.\n\nConclusionsWe found consistent evidence for a protective effect of morning preference and suggestive evidence for an adverse effect of sleep duration on breast cancer risk.

epidemiology↗