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Goncalves, C.

Publications and source records attributed to Goncalves, C..

At least 19 recordsLinked to original sources

DNA:RNA hybrid mutational landscapes reveal a common route to geneticinstability in evolving genomes

Pervasive DNA:RNA hybrids are recognized as pathological sources of genome instability, yet how their genotoxicity shapes mutational landscapes and genome evolution remains poorly understood. Here, we define the mutational footprint of hybrids by integrating genome-wide mapping, long-term mutation accumulation experiments, and analyses of genetic diversity across thousands of natural yeast genomes. We uncover signatures for embedded ribonucleotides and genic R-loops, together with a composite mutational pattern shared across natural populations and experimental evolution. Using reporters designed to dissect the mechanisms underlying genetic alterations, we find that they arise primarily from targeting by MutL{gamma}-dependent mismatch repair followed by Rad52-mediated recombination. Although hybrids form dynamically across the genome, their genotoxicity is strongly skewed toward repetitive regions susceptible to these error-prone pathways, including microsatellites and retroelements. Our findings reveal a common mechanism of hybrid-associated mutagenesis that can shape genetic variation in evolving genomes.

molecular biology↗

A triple fluorescent marker for live imaging of plant cell morphogenesis

Live imaging of plant subcellular structures is key to deciphering the spatiotemporal bases of cellular processes, and their functional impact on growth and morphogenesis at various biological scales. Live imaging of plant cells essentially relies on expression of fluorescent markers labeling cells or subcellular structures of interest. Simultaneous multi-channel imaging of several markers is still not routine practice in plant cell biology, owing to issues linked to genetic or spectral compatibility of markers, differences in expression levels, silencing, toxicity, etc. Here we designed a three-color marker in Arabidopsis thaliana and Capsella rubella, enabling high-resolution live imaging of plant morphogenesis, including labeling of the cell membrane, the nucleus and the microtubule cytoskeleton. Detection of MT arrays involved the development of a MAP4-MBD-based microtubule marker optimized for plant cells. The three-color marker allows visualization of the three-dimensional organization and dynamics of plant microtubules within the intracellular space with unprecedented precision, in various organs including the root and shoot meristems, the leaf, anther, and gynoecium. Our results demonstrate the potential of such single-construct strategy for cell biology studies in plants.

plant biology↗

A new mechanism of regulation of LIM kinases, LIMK1 and LIMK2, modulates their activity on cofilin and actin filament remodelling

LIM kinases, LIMK1 and LIMK2, play a crucial role in cytoskeleton dynamics. They are involved in many physiological processes but also in several pathologies such as cancer, neuronal diseases and neurofibromatosis. Although LIM kinases appear as promising therapeutic targets, they remain undruggable. A better understanding of their activity and regulation is thus required to better design efficient targeted therapies. Here, we have shown the impact of a single amino acid on LIMK activity on cofilin, their main substrate in actin filament remodelling. We demonstrated that Y632 and Y630, for LIMK1 and LIMK2 respectively, mediate LIMK dimerization, resulting in their transphosphorylation. This process seems to be a prerequisite for their canonical phosphorylation on their respective T508 and T505 residues within the activation loop. These Tyrosine are not phosphorylated, their aromatic nature is rather critical to ensure proper LIMK activity on cofilin. These results bring new insights into LIMK molecular features.

Molecular Biology↗

Systemic and tumor intrinsic expansion of FCRL5 expressing B cells associates with poor response to Bacillus Calmette-Guerin immunotherapy in patients with non-muscle invasive bladder cancer

The majority of patients treated with Bacillus Calmette-Guerin (BCG) immunotherapy, for non-muscle invasive bladder cancer (NMIBC), experience early recurrence due to pre-existing mucosal immune dysfunction. Since B cell are mucosal immune sentinels, we characterized the systemic and local B cell responses in 45 patients with NMIBC. Expansion of circulating atypical B cells (ABCs) following repeated BCG instillation, expanded IgG autoantibody repertoire, progressive IgG reactivity against BCG antigens, and higher tumor IgG deposition, were features of patients who recurred early. Integrated spatial immunophenotyping and single cell spatial transcriptomic analysis of corresponding tumors revealed increased ABCs within tertiary lymphoid structures, and co-localization with PD-1 B cells, regulatory T cells, and CD163 macrophages. Independent validation in two patient cohorts (total n = 409), revealed a significant association between high expression of the ABC specific, FCRL5, and poor outcomes. Our study identifies ABCs as key mediators of poor response to BCG in patients with high-risk NMIBC.

cancer biology↗

Discovery of additional ancient genome duplications in yeasts

Whole genome duplication (WGD) has had profound macroevolutionary impacts on diverse lineages1,2, preceding adaptive radiations in vertebrates3-5, teleost fish6,7, and angiosperms8,9. In contrast to the many known ancient WGDs in animals10,11 and especially plants12-14, we are aware of evidence for only four in fungi15,16. The oldest of these occurred [~]100 million years ago (mya) and is shared by [~]60 extant Saccharomycetales species17,18, including the bakers yeast Saccharomyces cerevisiae (Fig. 1). Notably, this is the only known ancient WGD in the yeast subphylum Saccharomycotina. The dearth of ancient WGD events in fungi remains a mystery15. Some studies have suggested that fungal lineages that experience chromosome19 and genome15 duplication quickly go extinct, leaving no trace in the genomic record, while others contend that the lack of known WGD is due to an absence of data15,16. Under the second hypothesis, additional sampling and deeper sequencing of fungal genomes should lead to the discovery of more WGD events. Coupling hundreds of recently published genomes from nearly every described Saccharomycotina species with three additional long-read assemblies, we discovered three novel WGD events. While the functions of retained duplicate genes originating from these events are broad, they bear many similarities to the well-known WGD that occurred in the Saccharomycetales17. Our results suggest that WGD may be a more common evolutionary force in fungi than previously believed. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=111 SRC="FIGDIR/small/673279v1_fig1.gif" ALT="Figure 1"> View larger version (29K): org.highwire.dtl.DTLVardef@6a8f47org.highwire.dtl.DTLVardef@1e4a790org.highwire.dtl.DTLVardef@b4e0eforg.highwire.dtl.DTLVardef@11b7795_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOFigure 1.C_FLOATNO Three additional whole genome duplications in Saccharomycotina yeasts. Rates of gene duplication are mapped onto Saccharomycetales (left) and Dipodascales (right) phylogenies. Whole genome duplications indicated along the lineages in which they are predicted to occur. Trees have been pruned for visualization purposes. C_FIG HighlightsO_LIEvidence for three whole genome duplications (WGDs) in Dipodascales yeasts C_LIO_LIImpacts of WGD are broad but bear many similarities to the known WGD in Saccharomycetales yeasts C_LIO_LIDuplicates with many protein-protein interactions are more likely to be retained over long timescales C_LIO_LIWGD in fungi is likely underreported C_LI

evolutionary biology↗

FrlP, an ABC type I importer component of Bacillus subtilis: regulation and impact in bacterial fitness

Bacillus subtilis is able to catabolize fructosamines, also known as Amadori rearrangement products. The frlBONMD-frlP operon mediates this process and is subjected to specific and global regulation. Although the degradation pathway favoring -glycated amino acids is known, the mechanisms of substrate uptake have remained unclear. In this study, mutagenic and functional analyses revealed that FrlONM, a type I ABC importer, along with the nucleotide-binding domain (NBD) FrlP, is required for the uptake of fructosevaline. Transcriptional and translation frlP-lacZ fusions indicated that frlP is induced by fructosevaline and negatively regulated by the FrlR repressor. Furthermore, by targeting an RNA molecule (S1254) encoded upstream from frlP and overlapping the repressor flrR gene transcribed in the opposite direction, we provide evidence for the dual regulation of frlP by this anti-sense RNA and FrlR. This result adds a posttranscriptional layer to the intricate regulation of the fructosamines operon. In addition, we show that MsmX, a multitask NBD of B. subtilis, is also able to serve as energy motor of this type I ABC importer, and that its presence alongside FrlP is vital for optimal growth on fructosevaline. To address the physiological significance of this functional redundancy we assessed the distribution of ABC type I NBDs FrlP and MsmX across the Bacillaceae family. MsmX is homogeneously distributed in Bacillaceae family tree, while FrlP is restricted to the Bacillus subtilis group, suggesting that the presence of FrlP together with other components of the fructosamines operon is important for bacteria fitness in plant-associated ecological niches. ImportanceBacillus subtilis is widely applied in the industry as a microbial cell factory, as a biofertilizer for sustainable agriculture, in the animal feed industry and as human probiotic. In its natural environment B. subtilis helps to shape the gut microbiome and the phytomicrobiome. Fructosamines, or Amadori rearrangement products, are ubiquitously found in nature and serve as precursors of toxic cell end-products implicated in the pathology of human diseases. This study provides a solid contribution to a deep knowledge of transport mechanisms, genetic regulation and physiological relevance of fructosamines utilization in B. subtilis. Moreover, it highlights an unusual strategy to adapt to alterations in nutrient availability by swapping the energy providing domain of ABC transporters.

microbiology↗

Stable hypermutators revealed by the genomic landscape of DNA repair genes among yeast species

Mutator phenotypes are short-lived due to the rapid accumulation of deleterious mutations. Yet, recent observations reveal that certain fungi can undergo prolonged accelerated evolution after losing DNA repair genes. Here, we surveyed 1,154 yeast genomes representing nearly all known yeast species of the subphylum Saccharomycotina to examine the relationship between reduced DNA repair repertoires and elevated evolutionary rates. We identified three distantly related lineages--encompassing 12% of species--with substantially reduced sets of DNA repair genes and the highest evolutionary rates in the entire subphylum. Two of these "faster-evolving lineages" (FELs)--a subclade within the order Pichiales and the Wickerhamiella/Starmerella (W/S) clade (order Dipodascales)--are described here for the first time, while the third corresponds to a previously documented Hanseniaspora FEL. Examination of DNA repair gene repertoires revealed a set of genes predominantly absent in these three FELs, suggesting a potential role in the observed acceleration of evolutionary rates. Genomic signatures in the W/S clade are consistent with a substantial mutational burden, including pronounced A|T bias and signatures of endogenous DNA damage. The W/S clade appears to mitigate UV-induced damage through horizontal acquisition of a bacterial photolyase gene, underscoring how gene loss may be offset by nonvertical evolution. These findings highlight how the loss of DNA repair genes gave rise to hypermutators that persist across macroevolutionary timescales, with horizontal gene transfer as an avenue for partial functional compensation.

evolutionary biology↗

RAB1A is a novel vulnerability in uveal melanoma revealed by dual inhibition of MNK1/2 and mTOR.

Uveal melanoma (UM) is an eye cancer that is fatal upon metastasis to the liver. Most treatments trialed in UM fail to provide therapeutic benefit, thus there is an urgent need for novel treatment strategies. The MAPK and PI3K signaling pathways, key molecular drivers found to be hyper-activated in UM, converge on the MNK1/2-eIF4E and mTORC1/2-4EBP axes. Here, we demonstrate that the pharmacologic inhibition of MNK1/2 in combination with an mTOR inhibitor impairs clonogenic outgrowth and UM cell invasion. Using proteomic analyses, we reveal that combined MNK1/2 and mTOR inhibition disrupts Golgi homeostasis and protein vesicle trafficking mainly due to downregulated RAB1A expression, a master regulator of intracellular protein transport. We uncover that the knockdown of RAB1A blocks liver metastasis, a result that is recapitulated by combined pharmacologic inhibition of MNK1/2 and mTOR. Finally, we show that RAB1A expression reshapes the surfaceome by increasing the abundance of plasma membrane proteins associated with poor overall survival in UM, highlighting its potential as a biomarker. This study identifies protein vesicle transport as an unrecognized vulnerability in UM and supports a mechanistic rationale for targeting MNK1/2 and mTOR in metastatic UM.

cancer biology↗

C.La.P.: Enhancing transformer-based genomic signal modeling by integrating DNA sequences and chromatin accessibility data

Transformers have shown promise in chromatin modeling but have primarily relied solely on reference DNA sequences, limiting their utility across multiple biological contexts. In this work we enhance transformer models by integrating reference sequences with ATAC-seq, a chromatin accessibility assay. Our Chromatin LAnguage Processing (CLaP) model combines a convolutional tokenizer, a transformer encoder, and task-specific components to predict multiple genomic signals from a single input. After pre-training with masked nucleotide prediction, CLaP achieved per-token F1 scores exceeding 0.8 for three target ChIP-seq assays in fine-tuning. Attention mechanism analysis revealed that CLaP detects CTCF binding sites with nucleotide-level precision by learning the sequence preference of the CTCF factor and the characteristic ATAC-seq patterns that are caused by protein binding events. Additionally, CLaP predicts protein-DNA binding events not captured by the ChIP-seq ground truth. These findings highlight CLaPs potential to expand chromatin modeling by incorporating molecular assay data alongside sequence information.

bioinformatics↗

The CCL17-CCR4 axis is critical for mutant STAT6-mediated microenvironmental remodelling and therapeutic resistance in Relapsed/Refractory Diffuse Large B Cell Lymphoma

Relapsed and refractory Diffuse Large B Cell Lymphoma (rrDLBCL) presents a significant challenge in hematology-oncology, with approximately 30-40% of DLBCL patients experiencing relapse or resistance to treatment. This underscores the urgent need to better understand the molecular mechanisms governing therapeutic resistance. Signal Transducer and Activator of Transcription 6 (STAT6) has been previously identified as a gene with recurrent D419 gain-of-function mutations in rrDLCBL. When STAT6D419 mutations are present in DLBCL tumour cells, we have demonstrated that transcription of the chemokine CCL17 (aka TARC) is increased, and tumours have increased infiltration of CD4+ T cells. However, the significance of increased T cell infiltration had not been determined. In the present study, we developed a mouse model of STAT6D419N mutant DLBCL, that recapitulates the critical features of human STAT6D419 mutant DLBCL, including increased expression of phospho-STAT6, increased CD4+ T cell invasion, and resistance to doxorubicin treatment. With this model, we found CD4+ T cells in STAT6D419N tumours have higher expression of the receptor for CCL17, CCR4. Using ex vivo functional assays we demonstrate that STAT6D419N tumour cells are directly chemoattractive to CCR4+ CD4+ T cells, and when CCR4 is inhibited using a small molecule antagonist, CD4+ T cells in STAT6D419N tumours are reduced and STAT6D419N tumours regain therapeutic sensitivity to doxorubicin. Using PhenoCycler imaging of human rrDLBCL samples, we find that STAT6D419 tumours indeed have increased expression of phospho-STAT6+ and increased cellular interactions between phospho-STAT6+ tumour cells and CD4+/ CCR4+ CD4+ T cells. Thus, our data identify CCR4 as an attractive therapeutic target in STAT6D419 mutant rrDLBCL.

cancer biology↗

A bifunctional snoRNA with separable activities in guiding rRNA 2'-O-methylation and scaffolding gametogenesis effectors

Small nucleolar RNAs are non-coding transcripts that guide chemical modifications of RNA substrates and modulate gene expression at the epigenetic and post-transcriptional levels. However, the extent of their regulatory potential and the underlying molecular mechanisms remain poorly understood. Here, we identify a conserved, previously unannotated intronic C/D-box snoRNA, termed snR107, hosted in the fission yeast long non-coding RNA mamRNA and carrying two independent cellular functions. On the one hand, snR107 guides site-specific 25S rRNA 2-O-methylation and promotes pre-rRNA processing and 60S subunit biogenesis. On the other hand, snR107 associates with the gametogenic RNA-binding proteins Mmi1 and Mei2, mediating their reciprocal inhibition and restricting meiotic gene expression during sexual differentiation. Both functions require distinct cis-motifs within snR107, including a conserved 2-O-methylation guiding sequence. Together, our results position snR107 as a dual regulator of rRNA modification and gametogenesis effectors, expanding our vision on the non-canonical functions exerted by snoRNAs in cell fate decisions.

molecular biology↗

Convergent reductive evolution in bee-associated lactic acid bacteria

AbstractDistantly related organisms may evolve similar traits when exposed to similar environments or engaging in certain lifestyles. Several members of the Lactobacillaceae (LAB) family are frequently isolated from the floral niche, mostly from bees and flowers. In some floral LAB species (henceforth referred to as bee- associated), distinctive genomic (e.g., genome reduction) and phenotypic (e.g., preference for fructose over glucose or fructophily) features were recently documented. These features are found across distantly related species, raising the hypothesis that specific genomic and phenotypic traits evolved convergently during adaptation to the floral environment. To test this hypothesis, we examined representative genomes of 369 species of bee-associated and non-bee-associated LAB. Phylogenomic analysis unveiled seven independent ecological shifts towards the floral niche in LAB. In these bee-associated LAB, we observed pervasive, significant reductions of genome size, gene repertoire, and GC content. Using machine leaning, we could distinguish bee-associated from non-bee-associated species with 94% accuracy, based on the absence of genes involved in metabolism, osmotic stress, or DNA repair. Moreover, we found that the most important genes for the machine learning classifier were seemingly lost, independently, in multiple bee-associated lineages. One of these genes, adhE, encodes a bifunctional aldehyde-alcohol dehydrogenase associated with the evolution of fructophily, a rare phenotypic trait that was recently identified in many floral LAB species. These results suggest that the independent evolution of distinctive phenotypes in bee- associated LAB has been largely driven by independent loss of the same set of genes. ImportanceSeveral lactic acid bacteria (LAB) species are intimately associated with bees and exhibit unique biochemical properties with potential for food applications and honeybee health. Using a machine-learning based approach, our study shows that adaptation of LAB to the bee environment was accompanied by a distinctive genomic trajectory deeply shaped by gene loss. Several of these gene losses occurred independently in distantly related species and are linked to some of their unique biotechnologically relevant traits, such as the preference of fructose over glucose (fructophily). This study underscores the potential of machine learning in identifying fingerprints of adaptation and detecting instances of convergent evolution. Furthermore, it sheds light onto the genomic and phenotypic particularities of bee-associated bacteria, thereby deepening the understanding of their positive impact on honeybee health.

evolutionary biology↗

Unique trajectory of gene family evolution from genomic analysis of nearly all known species in an ancient yeast lineage

Gene gains and losses are a major driver of genome evolution; their precise characterization can provide insights into the origin and diversification of major lineages. Here, we examined gene family evolution of 1,154 genomes from nearly all known species in the medically and technologically important yeast subphylum Saccharomycotina. We found that yeast gene family and genome evolution are distinct from plants, animals, and filamentous ascomycetes and are characterized by small genome sizes and smaller gene numbers but larger gene family sizes. Faster-evolving lineages (FELs) in yeasts experienced significantly higher rates of gene losses--commensurate with a narrowing of metabolic niche breadth--but higher speciation rates than their slower-evolving sister lineages (SELs). Gene families most often lost are those involved in mRNA splicing, carbohydrate metabolism, and cell division and are likely associated with intron loss, metabolic breadth, and non-canonical cell cycle processes. Our results highlight the significant role of gene family contractions in the evolution of yeast metabolism, genome function, and speciation, and suggest that gene family evolutionary trajectories have differed markedly across major eukaryotic lineages.

evolutionary biology↗

Predicted mechanistic impacts of human protein missense variants

Genome sequencing efforts have led to the discovery of tens of millions of protein missense variants found in the human population with the majority of these having no annotated role and some likely contributing to trait variation and disease. Sequence-based artificial intelligence approaches have become highly accurate at predicting variants that are detrimental to the function of proteins but they do not inform on mechanisms of disruption. Here we combined sequence and structure-based methods to perform proteome-wide prediction of deleterious variants with information on their impact on protein stability, protein-protein interactions and small-molecule binding pockets. AlphaFold2 structures were used to predict approximately 100,000 small-molecule binding pockets and stability changes for over 200 million variants. To inform on protein-protein interfaces we used AlphaFold2 to predict structures for nearly 500,000 protein complexes. We illustrate the value of mechanism-aware variant effect predictions to study the relation between protein stability and abundance and the structural properties of interfaces underlying trans protein quantitative trait loci (pQTLs). We characterised the distribution of mechanistic impacts of protein variants found in patients and experimentally studied example disease linked variants in FGFR1.

bioinformatics↗

A miniaturised semi-dynamic in-vitro model of human digestion

Reliable in-vitro digestion models that are able to successfully replicate the conditions found in the human gastrointestinal tract (GIT) are key to assess the fate and efficiency of new formulations aimed for oral consumption. However, current in-vitro models either lack the capability to replicate crucial dynamics of digestion or require large volumes of sample/reagents, which can be scarce when working with nanomaterials under development. Here, we propose a miniaturised digestion system, a digestion-chip, based on incubation chambers integrated on a polymethylmethacrylate (PMMA) device. The digestion-chip incorporates key dynamic features of human digestion, such as gradual acidification and gradual addition of enzymes and simulated fluids in the gastric phase, and controlled gastric emptying, while maintaining low complexity and using small volumes of sample and reagents. In addition, the new approach integrates real-time automated closed-loop control of two key parameters, pH and temperature, during the two main phases of digestion (gastric and intestinal) with an accuracy down to {+/-}0.1{degrees}C and {+/-}0.2 pH points. The experimental results demonstrate that the digestion-chip successfully replicates the gold standard static digestion INFOGEST protocol and that the semi-dynamic digestion kinetics can be reliably fitted to a first kinetic order model. These devices can be easily adapted to dynamic features in an automated, sensorised, and inexpensive platform and will enable reliable, low-cost and efficient assessment of the bioaccessibility of new and expensive drugs, bioactive ingredients or nano-engineered materials aimed for oral consumption, thereby avoiding unnecessary animal testing.

bioengineering↗

Functional and evolutionary integration of a fungal gene with a bacterial operon

Siderophores are crucial for iron-scavenging in microorganisms. While many yeasts can uptake siderophores produced by other organisms, they are typically unable to synthesize siderophores themselves. In contrast, Wickerhamiella/Starmerella (W/S) clade yeasts gained the capacity to make the siderophore enterobactin following the remarkable horizontal acquisition of a bacterial operon enabling enterobactin synthesis. Yet, how these yeasts absorb the iron bound by enterobactin remains unresolved. Here, we demonstrate that Enb1 is the key enterobactin importer in the W/S-clade species Starmerella bombicola. Through phylogenomic analyses, we show that ENB1 is present in all W/S clade yeast species that retained the enterobactin biosynthetic genes. Conversely, it is absent in species that lost the ent genes, except for Starmerella stellata, making this species the only cheater in the W/S clade that can utilize enterobactin without producing it. Through phylogenetic analyses, we infer that ENB1 is a fungal gene that likely existed in the W/S clade prior to the acquisition of the ent genes and subsequently experienced multiple gene losses and duplications. Through phylogenetic topology tests, we show that ENB1 likely underwent horizontal gene transfer from an ancient W/S clade yeast to the order Saccharomycetales, which includes the model yeast Saccharomyces cerevisiae, followed by extensive secondary losses. Taken together, these results suggest that the fungal ENB1 and bacterial ent genes were cooperatively integrated into a functional unit within the W/S clade that enabled adaptation to iron-limited environments. This integrated fungal-bacterial circuit and its dynamic evolution determines the extant distribution of yeast enterobactin producers and cheaters.

evolutionary biology↗

Tunable PhenoCycler Imaging of the Murine Pre-Clinical Tumour Microenvironments

The tumour microenvironment (TME) consists of tumour-supportive immune cells, endothelial cells, and fibroblasts. PhenoCycler, a high-plex single cell imaging platform, is used to characterize the complexity of the TME. Here, we used PhenoCycler to spatially resolve the TME of 8 routinely employed pre-clinical models of lymphoma, breast cancer, and melanoma. Our data reveal distinct TMEs in the different cancer models that were imaged, and show that cell-cell contacts differ depending on the tumour type examined. For instance, we found that the immune infiltration in a murine model of melanoma is altered in cellular organization in melanomas that become resistant to PD-1 therapy, with depletions in a number of cell-cell interactions. Furthermore, we provide detailed pipelines for the conjugation of antibodies that are optimized for PhenoCycler staining of murine FFPE tissues specifically, alongside open-source data analysis procedures. Overall, this is a valuable resource study seamlessly adaptable to any field of research involving murine models.

cancer biology↗

Diverse signatures of convergent evolution in cacti-associated yeasts

Many distantly related organisms have convergently evolved traits and lifestyles that enable them to live in similar ecological environments. However, the extent of phenotypic convergence evolving through the same or distinct genetic trajectories remains an open question. Here, we leverage a comprehensive dataset of genomic and phenotypic data from 1,049 yeast species in the subphylum Saccharomycotina (Kingdom Fungi, Phylum Ascomycota) to explore signatures of convergent evolution in cactophilic yeasts, ecological specialists associated with cacti. We inferred that the ecological association of yeasts with cacti arose independently [~]17 times. Using machine-learning, we further found that cactophily can be predicted with 76% accuracy from functional genomic and phenotypic data. The most informative feature for predicting cactophily was thermotolerance, which is likely associated with duplication and altered evolutionary rates of genes impacting the cell envelope in several cactophilic lineages. We also identified horizontal gene transfer and duplication events of plant cell wall-degrading enzymes in distantly related cactophilic clades, suggesting that putatively adaptive traits evolved through disparate molecular mechanisms. Remarkably, multiple cactophilic lineages and their close relatives are emerging human opportunistic pathogens, suggesting that the cactophilic lifestyle--and perhaps more generally lifestyles favoring thermotolerance--may preadapt yeasts to cause human disease. This work underscores the potential of a multifaceted approach involving high throughput genomic and phenotypic data to shed light onto ecological adaptation and highlights how convergent evolution to wild environments could facilitate the transition to human pathogenicity.

evolutionary biology↗