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Biology subjects

Watson, M.

Publications and source records attributed to Watson, M..

At least 19 recordsLinked to original sources

Proteogenomic Profiling Reveals a Distinct Endogenous p16INK4a-Associated Senescence Signature in the Human Ovary.

The tumor suppressor and cell cycle regulator, p16INK4a (p16), has been extensively linked to cellular senescence, and its accumulation can reflect endogenous senescence within ovarian tissue. However, gene and protein signatures associated with p16 have not been well defined in human tissue. We utilized immunohistochemical (IHC) staining for P16 to identify distinct positive (P16+) and negative (P16-) regions within the ovarian cortex and employed the GeoMx Digital Spatial Profiler for simultaneous proteomic and transcriptomic analyses on cortical tissue cores. Differential expression and translation between p16-positive and p16-negative cores identified genes and proteins that are cellular senescence related (e.g., CDKN1A, GADD45B, GADD45G, and MYC) or key regulators of the extracellular matrix (e.g., collagen I, ADAMTS4, and MMP11). Additionally, the transcriptomic signature identified here was significantly enriched for the spatially derived ovarian p16-associated signature, BuckSenOvary, but not for other senescence gene sets. Lastly, given the association between changes to the extracellular matrix in aged ovaries and ovarian cancer, we compared genes upregulated and downregulated in p16-positive regions relative to p16-negative regions against multiple ovarian cancer transcriptomic datasets. These findings provide new insight into the molecular landscape of naturally occurring ovarian senescence and its possible relationship to age-associated disease processes, including cancer development.

cell biology↗

Larp1 supports brain growth and spatial memory via post-transcriptional control of the translation machinery

In the brain, tight regulation of the translation of mRNAs is essential for development and plasticity. The translation machinery itself is largely encoded by mRNAs with terminal oligopyrimidine (TOP) motifs, which can be post-transcriptionally controlled by the mTOR signaling pathway. In neurons, these mRNAs are selectively enriched in axons, dendrites and synapses, suggesting local functions for their regulation. Here, we use a brain-specific knockout of the mTOR effector and TOP mRNA binding protein, Larp1, to uncover its role in brain development and behavior. Loss of Larp1 significantly decreases brain mass and reduces the density of neurons. We find that TOP mRNAs levels are depleted by more than 50% and selectively lost from synapses, reversing the enrichment that occurs when Larp1 is present. In behavior tests, Larp1-deficient mice are severely impaired in spatial learning and memory. These results demonstrate a critical role for Larp1 in maintaining the levels of essential mRNAs necessary for brain growth and highlight the importance of post-transcriptional regulation by mTOR for normal learning and memory.

neuroscience↗

Rakaia: interactive discovery of spatial biology at scale

Spatial biology data throughput currently outpaces interpretable analysis, limiting large-scale discovery and translation. Here we present Rakaia, a browser-based platform for multiplexed imaging and spatial transcriptomics, empowering code-free interactive exploration and evaluation. Rakaia enables visualization, annotation, and feature-based querying with prioritization across thousands of images. We use Rakaia to identify cell types of interest in >200 highly multiplexed images from non-malignant human breast tissue. Rakaia is available at: https://rakaia.io/

bioinformatics↗

Integrated spatial proteomics of human PDAC uncovers an expanded tumour-immune-stroma spectrum with genomic associations

Distinctively, pancreatic ductal adenocarcinoma (PDAC) consists of sparse tumour lesions intertwined with extensive desmoplastic stroma. The complexity of tumour-microenvironment interactions within this desmoplasia poses a challenge for accurate tumour profiling and patient stratification, and characterizes a profoundly chemoresistant tumour. Here we mapped the spatial relationships between tumour, stroma, and immune cell compartments delineating tumour and microenvironment types that expand the classical to basal spectrum of human PDAC. We used imaging mass cytometry to profile the in situ multi-cellular organization of 81 cell types in resected cases with paired whole genome sequencing. Cell types, functions, and pathway activation were distributed as highly reproducible environments in discrete locations throughout these tumours, which we deep-profiled using laser-capture mass spectrometry. We show that the connections between tumour phenotypes, vascularization, immune response, and stromal biophysical state are reinforced by genomic aberrations, altered by treatment, and associated with patient outcome. Predictive machine-learning models showed that spatial single cell data outperformed genomic or clinical features but integrated multi-omics models provide the best prediction of patient survival with compressed models requiring only 10 non-redundant robust molecular measures associated with the phenotypic spectrum of PDAC. Together, these findings define a phenotypic and molecular framework of PDAC that captures tumour-microenvironment co-dependencies and offers a refined basis for patient stratification and therapeutic targeting.

cancer biology↗

Drone methods and educational resources for plant science and agriculture

Technological advances have made drones (UAVs) increasingly important tools for the collection of trait data in plant science. Many costs for the analysis of plant populations have dropped precipitously in recent decades, particularly for genetic sequencing. Similarly, hardware advances have made it increasingly simple and practical to capture drone imagery of plant populations.However, converting this imagery into high-precision and high-throughput tabular data has become a major bottleneck in plant science. Here, we describe high-throughput phenotyping methods for the analysis of numerous plant traits based on imagery from diverse sensor types. Methods can be flexibly combined to extract data related to canopy temperature, area, height, volume, vegetation indices, and summary statistics derived from complex segmentations and classifications. We then describe educational and training resources for these methods, including a web page (PlantScienceDroneMethods.github.io) and an educational YouTube channel (https://www.youtube.com/@travisparkerplantscience) with step-by-step protocols, example data, and example scripts for the whole drone data processing pipeline. These resources facilitate the extraction of high-throughput and high-precision phenomic data, removing barriers to the phenomic analysis of large plant populations.

plant biology↗

Inhibition of the metalloprotease ADAM19 as a Novel Senomorphic Strategy to Ameliorate gut permeability and senescence markers by modulating senescence-associated secretory phenotype (SASP)

Accumulation of DNA damage can accelerate aging through cellular senescence. Previously, we established a Drosophila model to investigate the effects of radiation-induced DNA damage on the intestine. In this model, we examined irradiation-responsive senescence in the fly intestine. Through an unbiased genome-wide association study (GWAS) utilizing 156 strains from the Drosophila Genetic Reference Panel (DGRP), we identified meltrin {beta} (the drosophila orthologue of mammalian ADAM19) as a potential modulator of the senescence-associated secretory phenotype (SASP). Knockdown of meltrin {beta} resulted in reduced gut permeability, DNA damage, and expression of the senescence marker {beta}-galactosidase (SA-{beta}-gal) in the fly gut following irradiation. Additionally, inhibition of ADAM19 in mice using batimastat-94 reduced gut permeability and inflammation in the gut. Our findings extend to human primary fibroblasts, where ADAM19 knockdown or pharmacological inhibition decreased expression of specific SASP factors and SA-{beta}-gal. Furthermore, proteomics analysis of the secretory factor of senescent cells revealed a significant decrease in SASP factors associated with the ADAM19 cleavage site. These data suggest that ADAM19 inhibition could represent a novel senomorphic strategy.

molecular biology↗

Human stem cell-derived GABAergic interneuron development reveals early emergence of subtype diversity followed by gradual electrochemical maturation

Medial ganglionic eminence-derived inhibitory GABAergic pallial interneurons (MGE-pINs) are essential regulators of cortical circuits; their dysfunction is associated with numerous neurological disorders. We developed human (h) MGE-pINs from pluripotent stem cells for the treatment of drug-resistant epilepsy. Here, we analyzed xenografted hMGE-pINs over the lifespan of host mice using single nuclei RNA sequencing. Comparative transcriptomics against endogenous human brain datasets revealed that 97% of grafted cells developed into somatostatin (SST) and parvalbumin (PVALB) subtypes, including populations that exhibit selective vulnerability in Alzheimers disease. Transplanted hMGE-pINs demonstrated rapid emergence of subclass features, progressing through distinct transcriptional states sequentially involving neuronal migration, synapse organization, and membrane maturation. We present molecular, electrophysiological, and morphological data that collectively confirm the derivation of diverse bona-fide human SST and PVALB subtypes, providing a high-fidelity model to study human MGE-pIN development and functional maturation as well as a compositional atlas for regenerative cell therapy applications.

neuroscience↗

Interactive design and validation of antibody panels using single-cell RNA-seq atlases

Single-cell RNA-sequencing holds promise for identifying novel markers of cellular variation for antibody-based technologies. However, antibody panel design is often difficult due to multiple experimental and biological constraints. We introduce Cytomarker, an interactive platform enabling human-in-the-loop design of antibody panels from single-cell transcriptomic data. We use Cytomarker to spatially profile human mammary tissue subpopulations and develop a novel antibody screening approach to validate granular subpopulation predictions across >3.5M cells.

bioinformatics↗

A comprehensive multi-omics signature of doxorubicin-induced cellular senescence in the postmenopausal human ovary.

A major aging hallmark is the accumulation of cellular senescence burden. Over time senescent cells contribute to tissue deterioration through chronic inflammation and fibrosis driven by the Senescence-Associated Secretory Phenotype (SASP). The human ovary is one of the first organs to age, and prominent age-related fibroinflammation within the ovarian microenvironment is consistent with the presence of senescent cells, but these cells have not been characterized in the human ovary. We thus established a doxorubicin-induced model of cellular senescence to establish a "senotype" (gene/protein signature of a senescence cell state) for ovarian senescent cells. Explants of human postmenopausal ovarian cortex and medulla were treated with doxorubicin for 24 hours followed by culture for up to 10 days in a doxorubicin-free medium. Tissue viability was confirmed by histology, lack of apoptosis, and continued glucose consumption by explants. Single nuclei sequencing and proteomics revealed an unbiased signature of ovarian senescence. We identified distinct senescence profiles for the cortex and medulla, driven predominantly by epithelial and stromal cells. Proteomics uncovered subregional differences in addition to 120 proteins common to the cortex and medulla SASP. Integration of transcriptomic and proteomic analyses revealed 26 shared markers, defining a senotype of doxorubicin-induced senescence unique to the postmenopausal ovary. A subset of these proteins: Lumican, SOD2, MYH9, and Periostin were mapped onto native tissue to reveal compartment-specific localization. This senotype will help determine the role of cellular senescence in ovarian aging, inform biomarker development to identify, and therapeutic applications to slow or reverse ovarian aging, senescence, and cancer.

molecular biology↗

Determining the culturability of the bovine rumen bacterial and archaeal microbiota

Ruminants play an important part in global food security, but also emit methane which contributes to global warming. Microbes in the rumen strongly influence the energy retention efficiency from the hosts plant-based diet and produce methane as a by-product. While thousands of novel microbial genomes have been assembled from metagenome sequence data, their culturability is ill-defined. Here different media were used to isolate microbes from rumen fluid. 34 genera were grown, and the majority belonged to the phylum Bacillota (75.28% {+/-} 6.34), Bacteroidota (19.99% {+/-} 4.85), Pseudomonadota (2.46% {+/-} 2.01), and Actinomycetota (2.09% {+/-} 1.07). The most abundant genera were Selenomonas (28.08% {+/-} 11.71), Streptococcus (22.67% {+/-} 6.06), Prevotella (18.71% {+/-} 4.02), and unclassified Lachnospiraceae (11.50% {+/-} 2.54). When comparing the mean relative abundance of these genera between media, 31 were significantly enriched on at least one medium. The composition of the source rumen fluid was vastly different to those cultured. Bacteroidota (52.53% {+/-} 5.10) predominated, with by Bacillota (41.00% {+/-} 3.96), the archaeal Euryarchaeota (5.12% {+/-} 1.94), Pseudomonadota (1.22% {+/-} 0.78), and Actinomycetota (0.12% {+/-} 0.08) comprising the rest. The most abundant genera were Prevotella (29.13% {+/-} 4.16), Butyrivibrio (18.21% {+/-} 2.08), Succiniclasticum (15.57% {+/-} 5.03), unclassified Bacteroidetes (13.91% {+/-} 1.67), and unclassified Prevotellaceae (9.50% {+/-} 2.01). These data further emphasise the importance of using defined media to selectively enrich for different microbial taxa. This is essential to understand the complex workings of the rumen microbes to enhance digestion efficiency and reduce the loss of energy as methane.

microbiology↗

Methanogenesis inhibition remodels microbial fermentation and stimulates acetogenesis in ruminants

Rumen microbiota enable ruminants to grow on fibrous plant materials but also produce methane, driving 5% of global greenhouse gas emissions and leading to a loss of gross energy content. Methanogenesis inhibitors such as 3-nitrooxypropanol (3-NOP) decrease methane emissions in ruminants when supplemented in feed. Yet we lack a system-wide, species-resolved understanding of how the rumen microbiota remodels following inhibition and how this influences animal production. Here, we conducted a large-scale trial with 51 dairy calves to analyse microbiota responses to 3-NOP, pairing host performance, emissions, and nutritional profiles with genome-resolved metagenomic and metatranscriptomic data. 3-NOP supplementation decreased methane emissions by an average of 62%, modulated short-chain fatty acid and H2 levels, and did not affect dietary intake or animal performance. We created a rumen microbial genome catalogue with an unprecedented mapping rate. We observed a strong reduction of methanogens and stimulation of reductive acetogens, primarily novel uncultivated lineages such as Candidatus Faecousia. However, there was a shift in major fermentative communities away from acetate production in response to hydrogen gas accumulation. Thus, the divergent responses of the fermentative and hydrogenotrophic communities limit potential productivity gains from methane reduction. Reporting one of the largest reductions in methane emissions in a field trial to date, this study links ruminant greenhouse gas emissions and productivity to specific microbial species. These findings also emphasise the importance of microbiota-wide analysis for optimising methane mitigation strategies and identify promising strategies to simultaneously reduce emissions while increasing animal production. Significance StatementOne strategy to increase the sustainability and productivity of livestock production is to modulate ruminant microbiota to produce absorbable nutrients rather than the potent greenhouse gas methane. Previous studies show supplementing feed with methanogenesis inhibitors such as 3-nitrooxypropanol reduces methane emissions, but also leads to inconsistent productivity gains. Here we report a definitive field trial, combining animal data, meta-omics, and structural modelling, to resolve the key microbes and pathways controlling nutrient and methane production in ruminants. We show that shifts in composition and gene expression of hydrogen-cycling microbes reduce emissions but limit productivity gains. These findings offer insights at unprecedented resolution, while the data and analytical framework provide valuable resources to develop solutions to enhance livestock productivity and sustainability.

microbiology↗

A pumpless and tubeless microfluidic device enables extended in vitro development of Cryptosporidium parvum

The enteric parasite Cryptosporidium remains a treatment challenge for drinking water utilities globally due to its resistance to chlorine disinfection. However, the lack of an in vitro culture system for Cryptosporidium that is both cost-effective and reliable remains a key bottleneck in Cryptosporidium research. Here we report that the microfluidic culture of HCT-8 cells under fluid shear stress enables the extended development of Cryptosporidium parvum. Specifically, the growth of C. parvum in a user-friendly pumpless microfluidic device was assessed using immunofluorescence assays, scanning electron microscopy and quantitative PCR, which revealed that development peaked at six days post-infection but continued for ten days in total. Oocysts produced within the microfluidic device were infective to fresh HCT-8 monolayers, however these oocysts were only present at low levels. We anticipate that such microfluidic approaches will facilitate a wide range of in vitro studies on Cryptosporidium and may have the potential to be further developed as a routine infectivity assessment tool for the water industry.

microbiology↗

Senescent cell heterogeneity and responses to senolytic treatment are related to cell cycle status during cell growth arrest.

Cellular senescence has been strongly linked to aging and age-related diseases. It is well established that the phenotype of senescent cells is highly heterogeneous and influenced by their cell type and senescence-inducing stimulus. Recent single-cell RNA-sequencing studies identified heterogeneity within senescent cell populations. However, proof of functional differences between such subpopulations is lacking. To identify functionally distinct senescent cell subpopulations, we employed high-content image analysis to measure senescence marker expression in primary human endothelial cells and fibroblasts. We found that G2-arrested senescent cells feature higher senescence marker expression than G1-arrested senescent cells. To investigate functional differences, we compared IL-6 secretion and response to ABT263 senolytic treatment in G1 and G2 senescent cells. We determined that G2-arrested senescent cells secrete more IL-6 and are more sensitive to ABT263 than G1-arrested cells. We hypothesize that cell cycle dependent DNA content is a key contributor to the heterogeneity within senescent cell populations. This study demonstrates the existence of functionally distinct senescent subpopulations even in culture. This data provides the first evidence of selective cell response to senolytic treatment among senescent cell subpopulations. Overall, this study emphasizes the importance of considering the senescent cell heterogeneity in the development of future senolytic therapies.

cell biology↗

Exosomes Released from Senescent Cells and Circulatory Exosomes Isolated from Human Plasma Reveal Aging-associated Proteomic and Lipid Signatures

Senescence emerged as significant mechanism of aging and age-related diseases, offering an attractive target for clinical interventions. Senescent cells release a senescence-associated secretory phenotype (SASP), including exosomes that may act as signal transducers between distal tissues, propagating secondary or bystander senescence and signaling throughout the body. However, the composition of exosome SASP remains underexplored, presenting an opportunity for novel unbiased discovery. We present a detailed proteomic and lipidomic analysis of exosome SASP using mass spectrometry from human plasma from young and older individuals and from tissue culture of senescent primary human lung fibroblasts. We identified [~]1,300 exosome proteins released by senescent cells induced by three different senescence inducers. In parallel, a human plasma cohort from young (20-26 years) and old (65-74 years) individuals revealed over 1,350 exosome proteins and 171 plasma exosome proteins were regulated when comparing old vs young individuals. Of the age-regulated plasma exosome proteins, we observed 52 exosome SASP factors that were also regulated in exosomes from the senescent fibroblasts, including serine protease inhibitors (SERPINs), Prothrombin, Coagulation factor V, Plasminogen, and Reelin. 247 lipids were identified in exosome samples. Following senescence induction, identified phosphatidylcholines, phosphatidylethanolamines, and sphingomyelins increased significantly indicating cellular membrane changes. Interestingly, significantly changed proteins were related to extracellular matrix remodeling and inflammation, both potentially detrimental pathways that can damage surrounding tissues and even induce secondary senescence. Our findings reveal mechanistic insights and potential senescence biomarkers, enabling a better approach to surveilling the senescence burden in the aging population and offering therapeutic targets for interventions.

cell biology↗

Infectious bronchitis virus vaccination, but not the presence of XCR1, is correlated with large differences in chicken caecal microbiota

The chicken immune system and microbiota play vital roles in maintaining gut homeostasis and protecting against pathogens. In mammals, XCR1+ conventional dendritic cells (cDCs) are located in the gut-draining lymph nodes and play a major role in gut homeostasis. These cDCs sample antigens in the gut luminal contents and limit the inflammatory response to gut commensal microbes by generating appropriate regulatory and effector T-cell responses. We hypothesised that these cells play similar roles in sustaining gut homeostasis in chickens, and that chickens lacking XCR1 were likely to contain a dysbiotic caecal microbiota. Here we compare the caecal microbiota of chickens that were either heterozygous or homozygous XCR1 knockouts, that had or had not been vaccinated for infectious bronchitis virus (IBV). We used short-read (Illumina) and long-read (PacBio HiFi) metagenomic sequencing to reconstruct 670 high-quality, strain-level metagenome assembled genomes. We found no significant differences between alpha-diversity or the abundance of specific microbial taxa between genotypes. However, IBV vaccination was found to correlate with significant differences in the richness and beta-diversity of the microbiota, and to the abundance of forty bacterial genera. In conclusion, we found that a lack of XCR1 was not correlated with significant changes in the chicken microbiota, but IBV vaccination was. Data SummaryThe raw sequencing data for this project, as well as primary assemblies, putative genome bins and species-level MAGs, are available in the European Nucleotide Archive under project PRJEB64517. Strain-level MAGs are available through Edinburgh DataShare (https://doi.org/10.7488/ds/7678). Impact statementChickens play a vital role in global food systems, with 74 billion chickens killed for meat and 1.6 trillion chicken eggs produced in 2021 alone. The gut microbiota plays a vital role in the health and nutrition of the chicken, contributing to gut homeostasis and the production of nutrients that can be absorbed and used by the host bird. The chicken gut microbiota represents an excellent target to improve pathogen resistance and nutrition, as farmed chickens are not exposed to a maternal hen and thereby develop a low-diversity gut microbiota that negatively impacts their immune development and gut health. In order to develop such microbiota interventions, we first need to understand the fundamental biology behind immune-microbiota interactions. While it is well known that the chicken gut microbiota plays an important role in gut homeostasis, the mechanisms behind this phenomenon are poorly understood. In mammals, XCR1+ conventional dendritic cells have been shown to play a role in maintaining gut homeostasis. In this study we compare the gut microbiota of heterozygous and homozygous XCR1 knockout chickens that did or did not receive infectious bronchitis virus vaccination. We found that the gut microbiota of heterozygous and homozygous XCR1 knockout chickens did not differ significantly, but IBV vaccination did significantly correlate with differences in the microbiota composition.

microbiology↗

A DNA condensation code for linker histones

Linker histones play an essential role in chromatin packaging by facilitating compaction of the 11-nm fibre of nucleosomal "beads on a string". The result is a heterogeneous condensed state with local properties that range from dynamic, irregular and liquid-like, to stable and regular structures (the 30-nm fibre), which in turn impact chromatin-dependent activities at a fundamental level. The properties of the condensed state depend on the type of linker histone, particularly on the highly disordered C-terminal tail, which is the most variable region of the protein, both between species, and within the various subtypes and cell-type specific variants of a given organism. We have developed an in-vitro model system comprising linker histone tail and linker DNA, which although very minimal, displays surprisingly complex behaviour, and is sufficient to model the known states of linker-histone-condensed chromatin: disordered "fuzzy" complexes ("open" chromatin), dense liquid-like assemblies (dynamic condensates) and higher-order structures (organised 30-nm fibres). A crucial advantage of such a simple model is that it allows the study of the various condensed states by NMR, CD and scattering methods. Moreover, it allows capture of the thermodynamics underpinning the transitions between states through calorimetry. We have leveraged this to rationalise the distinct condensing properties of linker histone subtypes and variants across species that are encoded by the amino acid content of their C-terminal tails. Three properties emerge as key to defining the condensed state: charge density, lysine/arginine ratio, and proline-free regions, and we evaluate each separately using a strategic mutagenesis approach.

biophysics↗

Combinatorial immune refocusing within the influenza hemagglutinin head elicits cross-neutralizing antibody responses

The head domain of influenza hemagglutinin (HA) elicits potently neutralizing yet mostly strain-specific antibodies during infection and vaccination. Here we evaluated a series of immunogens that combined several immunofocusing techniques for their ability to enhance the functional breadth of vaccine-elicited immune responses. We designed a series of "trihead" nanoparticle immunogens that display native-like closed trimeric heads from the HAs of several H1N1 influenza viruses, including hyperglycosylated variants and hypervariable variants that incorporate natural and designed sequence diversity at key positions in the periphery of the receptor binding site (RBS). Nanoparticle immunogens displaying triheads or hyperglycosylated triheads elicited higher HAI and neutralizing activity against vaccine-matched and -mismatched H1 viruses than corresponding immunogens lacking either trimer-stabilizing mutations or hyperglycosylation, indicating that both of these engineering strategies contributed to improved immunogenicity. By contrast, mosaic nanoparticle display and antigen hypervariation did not significantly alter the magnitude or breadth of vaccine-elicited antibodies. Serum competition assays and electron microscopy polyclonal epitope mapping revealed that the trihead immunogens, especially when hyperglycosylated, elicited a high proportion of antibodies targeting the RBS, as well as cross-reactive antibodies targeting a conserved epitope on the side of the head. Our results yield important insights into antibody responses against the HA head and the ability of several structure-based immunofocusing techniques to influence vaccine-elicited antibody responses. HIGHLIGHTSO_LIGeneralization of trihead antigen platform to several H1 hemagglutinins, including hyperglycosylated and hypervariable variants C_LIO_LITrimer-stabilizing mutations in trihead nanoparticle immunogens lead to lower levels of non-neutralizing antibody responses in both mice and rabbits C_LIO_LIHyperglycosylated triheads elicit higher antibody responses against broadly neutralizing epitopes C_LI

immunology↗

KOunt - A reproducible KEGG orthologue abundance workflow

SummaryAccurate gene prediction is essential for successful metagenome analysis. We present KOunt, a Snake-make pipeline, that precisely quantifies KEGG orthologue abundance. Availability and implementationKOunt is available on GitHub: https://github.com/WatsonLab/KOunt. The KOunt reference database is available on figshare: https://figshare.com/s/72fe3ed7dfbbdcd8b1e5. Test data are available at https://figshare.com/ndownloader/files/39545968 and version 1.1.0 of KOunt at https://figshare.com/ndown-loader/files/39547273. Contactjennifer.mattock@roslin.ed.ac.uk Supplementary informationSupplementary data are available at Bioinformatics online.

bioinformatics↗