Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK.
Department of Biological Sciences, Columbia University, New York City, NY 10027, USA.
Development. 2024 Oct 15;151(20). doi: 10.1242/dev.202821. Epub 2024 Aug 7.
Vertebrate calcitonin-producing cells (C-cells) are neuroendocrine cells that secrete the small peptide hormone calcitonin in response to elevated blood calcium levels. Whereas mouse C-cells reside within the thyroid gland and derive from pharyngeal endoderm, avian C-cells are located within ultimobranchial glands and have been reported to derive from the neural crest. We use a comparative cell lineage tracing approach in a range of vertebrate model systems to resolve the ancestral embryonic origin of vertebrate C-cells. We find, contrary to previous studies, that chick C-cells derive from pharyngeal endoderm, with neural crest-derived cells instead contributing to connective tissue intimately associated with C-cells in the ultimobranchial gland. This endodermal origin of C-cells is conserved in a ray-finned bony fish (zebrafish) and a cartilaginous fish (the little skate, Leucoraja erinacea). Furthermore, we discover putative C-cell homologs within the endodermally-derived pharyngeal epithelium of the ascidian Ciona intestinalis and the amphioxus Branchiostoma lanceolatum, two invertebrate chordates that lack neural crest cells. Our findings point to a conserved endodermal origin of C-cells across vertebrates and to a pre-vertebrate origin of this cell type along the chordate stem.
脊椎动物降钙素产生细胞 (C 细胞) 是神经内分泌细胞，在血钙水平升高时分泌降钙素这种小肽激素。虽然小鼠 C 细胞位于甲状腺内，来源于咽内胚层，但禽类 C 细胞位于鳃后腺内，据报道来源于神经嵴。我们在一系列脊椎动物模型系统中使用比较细胞谱系追踪方法来解决脊椎动物 C 细胞的祖先胚胎起源问题。我们发现，与先前的研究相反，鸡 C 细胞来源于咽内胚层，而神经嵴衍生的细胞则有助于与鳃后腺中的 C 细胞密切相关的结缔组织。这种 C 细胞的内胚层起源在有颌鱼类（斑马鱼）和软骨鱼类（小鳐鱼，Leucoraja erinacea）中是保守的。此外，我们在无脊椎脊索动物文昌鱼（Ciona intestinalis）和海鞘（Branchiostoma lanceolatum）的内胚层衍生咽上皮中发现了推定的 C 细胞同源物，这两种无脊椎脊索动物都缺乏神经嵴细胞。我们的发现表明，C 细胞在脊椎动物中具有保守的内胚层起源，并且这种细胞类型在脊索动物的主干中具有前脊椎动物起源。
