RESUMO
Cell types are the basic building units of multicellular life, with extensive diversities. The evolution of cell types is a crucial layer of comparative cell biology but is thus far not comprehensively studied. We define a compendium of cell atlases using single-cell RNA-seq (scRNA-seq) data from seven animal species and construct a cross-species cell-type evolutionary hierarchy. We present a roadmap for the origin and diversity of major cell categories and find that muscle and neuron cells are conserved cell types. Furthermore, we identify a cross-species transcription factor (TF) repertoire that specifies major cell categories. Overall, our study reveals conservation and divergence of cell types during animal evolution, which will further expand the landscape of comparative genomics.
Assuntos
Linhagem da Célula , Evolução Molecular , Perfilação da Expressão Gênica , Células Musculares/metabolismo , Neurônios/metabolismo , Análise de Célula Única , Fatores de Transcrição/genética , Transcriptoma , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Ciona intestinalis/genética , Ciona intestinalis/metabolismo , Bases de Dados Genéticas , Regulação da Expressão Gênica no Desenvolvimento , Genômica , Humanos , Camundongos , Células Musculares/classificação , Neurônios/classificação , Especificidade da Espécie , Fatores de Transcrição/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismoRESUMO
Muscle cells of a digenean fish blood fluke, Aporocotyle simplex, aggregate along the periphery of the cerebral ganglia. Solitary myocytons and sarcoplasmic processes with muscle fibres give rise to long, narrow lamellate projections, which are visible along the periphery and within ganglia. These ultrastructural observations suggest a switching of glial functions to muscle cells and represent additional evidence of the phylogenetic lability of glial cells in bilaterians.
