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Cardoso-Moreira, M.

Publications and source records attributed to Cardoso-Moreira, M..

7 recordsLinked to original sources

The origin and molecular evolution of the mammalian liver cell architecture

The liver is a central organ with essential roles in processes such as nutritional metabolism, detoxification, and immune defense1-6. It has been instrumental in the adaptation of mammalian species to diverse environments, as reflected by its rapid molecular evolution7,8. However, the origins and evolutionary dynamics of liver cell types and their structural organization remain largely unexplored. Here we report evolutionary analyses of transcriptome and chromatin accessibility data for liver cells from 17 species, spanning all major feeding strategies (herbivory, omnivory, carnivory, insectivory), great apes (including humans), placental clades (Afrotheria, Xenarthra, Laurasiatheria, Euarchontoglires), major mammalian lineages (placentals, marsupials, monotremes), and a bird as outgroup. Integrated with spatial transcriptomics, our data reveal that liver zonation--the compartmentalization of hepatocyte functions along the lobule, the livers fundamental anatomical and functional unit--is conserved across mammals but absent in other vertebrates. We find that zonation originated in the mammalian ancestor, driven by the emergence of WNT and R-spondin signaling from central vein endothelial cells, which activate central hepatocyte gene expression via the transcription factor TCF7L2. Despite this conserved architecture and signaling, genes with zonated expression exhibit rapid evolutionary turnover. Consistently, hepatocytes evolve fast, likely due to reduced selective constraints, enabling adaptive changes under positive selection. Alongside immune cells, hepatocytes are therefore key drivers of the livers rapid evolution and functional innovations. In great apes, we identify human-specific shifts in zonation and cell-type-specific expression linked to recent cis-regulatory changes, particularly in genes involved in lipid metabolism, likely contributing to human-specific metabolic traits. Our study uncovers the origins of a mammal-specific liver cell architecture, within which reduced constraints facilitated molecular changes underlying ecological adaptations.

evolutionary biology↗

The evolution of gene regulatory programs controlling gonadal development in primates

Sex-determining pathways produce dimorphic gonads (ovaries and testes), yet the gene regulatory programs governing gonadogenesis and their evolution in primates remain little explored. Here we report evolutionary analyses of transcriptome and chromatin accessibility data of male and female human, marmoset (New World monkey), and mouse gonadal cells spanning key prenatal stages. We find that the two primates and mouse share similar X chromosome expression dynamics, including X chromosome reactivation (XCR), and that in Klinefelter syndrome (XXY) testes, germ cells undergo female-like XCR and escape of X inactivation. New male-specific regulatory regions have emerged progressively during mammalian evolution, especially on the X following sex chromosome origination. Further analyses revealed that male-specific regulatory regions evolved faster than female-specific ones in both supporting and pre-meiotic germ cells. However, female meiotic germ cells show even higher rates of molecular evolution and exhibit a permissive chromatin state that facilitates the birth of new genes, thus resembling their adult spermatogenic counterparts. Finally, we traced both conserved and species-specific gene expression trajectories across the three mammals, uncovering candidate genes for disorders of sex development that are typically central to cell-type-specific regulatory networks. Together, our study unveils both ancestral mammalian and recently evolved gene regulatory programs that control human- and primate-specific aspects of gonadal development in both sexes.

evolutionary biology↗

The evolution of gene regulation in mammalian cerebellum development

Gene regulatory changes are considered major drivers of evolutionary innovations, including the cerebellums expansion during human evolution, yet they remain largely unexplored. In this study, we combined single-nucleus measurements of gene expression and chromatin accessibility from six mammals (human, bonobo, macaque, marmoset, mouse, and opossum) to uncover conserved and diverged regulatory networks in cerebellum development. We identified core regulators of cell identity and developed sequence-based models that revealed conserved regulatory codes. By predicting chromatin accessibility across 240 mammalian species, we reconstructed the evolutionary histories of human cis-regulatory elements, identifying sets associated with positive selection and gene expression changes, including the recent gain of THRB expression in cerebellar progenitor cells. Collectively, our work reveals the shared and mammalian lineage-specific regulatory programs governing cerebellum development.

evolutionary biology↗

Cellular development and evolution of the mammalian cerebellum

The expansion of the neocortex, one of the hallmarks of mammalian evolution1,2, was accompanied by an increase in the number of cerebellar neurons3. However, little is known about the evolution of the cellular programs underlying cerebellum development in mammals. In this study, we generated single-nucleus RNA-sequencing data for [~]400,000 cells to trace the development of the cerebellum from early neurogenesis to adulthood in human, mouse, and the marsupial opossum. Our cross-species analyses revealed that the cellular composition and differentiation dynamics throughout cerebellum development are largely conserved, except for human Purkinje cells. Global transcriptome profiles, conserved cell state markers, and gene expression trajectories across neuronal differentiation show that the cerebellar cell type-defining programs have been overall preserved for at least 160 million years. However, we also discovered differences. We identified 3,586 genes that either gained or lost expression in cerebellar cells in one of the species, and 541 genes that evolved new expression trajectories during neuronal differentiation. The potential functional relevance of these cross-species differences is highlighted by the diverged expression patterns of several human disease-associated genes. Altogether, our study reveals shared and lineage-specific programs governing the cellular development of the mammalian cerebellum, and expands our understanding of the evolution of mammalian organ development.

evolutionary biology↗

The molecular evolution of spermatogenesis across mammals

The testis is a key male reproductive organ that produces gametes through the process of spermatogenesis. Testis morphologies and spermatogenesis evolve rapidly in mammals, presumably due to the evolutionary pressure on males to be reproductively successful1,2. The rapid evolution of the testis was shown to be reflected at the molecular level based on bulk-tissue work3-8, but the molecular evolution of individual spermatogenic cell types across mammalian lineages remains largely uncharacterized. Here we report evolutionary analyses of single-nucleus transcriptome data for testes from eleven species that cover the three major mammalian lineages (eutherians, marsupials, egg-laying monotremes) and birds (the evolutionary outgroup), and include seven key primates. Our analyses reveal that the rapid evolution of the testis is driven by accelerated fixation rates of gene expression changes, amino acid altering substitutions, and newly emerged genes in late spermatogenic stages - likely facilitated by reduced pleiotropic constraints, haploid selection, and a transcriptionally permissive chromatin environment. We identify temporal expression changes of individual genes across species, which may have contributed to the emergence of species-specific phenotypes, but also conserved expression programs underlying ancestral spermatogenic processes. Sex chromosome analyses show that genes predominantly expressed in spermatogonia (i.e., germ cells fueling spermatogenesis) and Sertoli cells (i.e., somatic supporting cells) independently accumulated on X chromosomes across mammals during evolution, presumably due to male-beneficial selective forces. Further work uncovered that the process of meiotic sex chromosome inactivation (MSCI) also occurs in monotremes and hence is common to the different mammalian sex chromosome systems, contrary to previous inferences9. Thus, the general mechanism of meiotic silencing of unsynapsed chromatin (MSUC), which underlies MSCI, represents an ancestral mammalian feature. Together, our study illuminates the cellular and molecular evolution of mammalian spermatogenesis and associated selective forces, and provides a resource for investigating the biology of the testis across mammals.

evolutionary biology↗

The regulatory landscape of cells in the developing mouse cerebellum

Organ development is orchestrated by cell- and time-specific gene regulatory networks. Here we investigated the regulatory basis of mouse cerebellum development from early neurogenesis to adulthood. By acquiring snATAC-seq profiles for ~90,000 cells spanning eleven stages, we mapped all major cerebellar cell types and identified candidate cis-regulatory elements (CREs). We detected extensive spatiotemporal heterogeneity among progenitor cells and characterized the regulatory programs underlying the differentiation of cerebellar neurons. Although CRE activity is predominantly cell type- and time-specific, periods of greater regulatory change are shared across cell types. There is a universal decrease in CRE conservation and pleiotropy during development and differentiation, but the degree of evolutionary constraint differs between cerebellar cell types. Our work delineates the developmental and evolutionary dynamics of gene regulation in cerebellar cells and provides general insights into mammalian organ development.

genomics↗

Developmental gene expression differences between humans and mammalian models

Identifying the molecular programs underlying human organ development and how they differ from those in model species will advance our understanding of human health and disease. Developmental gene expression profiles provide a window into the genes underlying organ development as well as a direct means to compare them across species. We use a transcriptomic resource for mammalian organ development to characterize the temporal profiles of human genes associated with distinct disease classes and to determine, for each human gene, the similarity of its spatiotemporal expression with its orthologs in rhesus macaque, mouse, rat and rabbit. We find that half of human genes differ from their mouse orthologs in their temporal trajectories. These include more than 200 disease genes associated with brain, heart and liver disease, for which mouse models should undergo extra scrutiny. We provide a new resource that evaluates for every human gene its suitability to be modeled in different mammalian species.

genomics↗