Project description:Animal pigment patterns play important roles in behavior and, in many species, red coloration serves as an honest signal of individual quality in mate choice. Among Danio fishes, some species develop erythrophores, pigment cells that contain red ketocarotenoids, whereas other species, like zebrafish (D. rerio) only have yellow xanthophores. Here, we use pearl danio (D. albolineatus) to assess the developmental origin of erythrophores and their mechanisms of differentiation. We show that erythrophores in the fin of D. albolineatus share a common progenitor with xanthophores and maintain plasticity in cell fate even after differentiation. We further identify the predominant ketocarotenoids that confer red coloration to erythrophores and use reverse genetics to pinpoint genes required for the differentiation and maintenance of these cells. Our analyses are a first step towards defining the mechanisms underlying the development of erythrophore-mediated red coloration in Danio and reveal striking parallels with the mechanism of red coloration in birds.
Project description:Understanding genetic and cellular bases of adult form remains a fundamental goal at the intersection of developmental and evolutionary biology. The skin pigment cells of vertebrates, derived from embryonic neural crest, are a useful system for elucidating mechanisms of fate specification, pattern formation, and how particular phenotypes impact organismal behavior and ecology. In a survey of Danio fishes, including zebrafish Danio rerio, we identified two populations of white pigment cells—leucophores—one of which arises by transdifferentiation of adult melanophores and another that develops from a yellow/orange xanthophore-like progenitor. Single-cell transcriptomic, mutational, chemical and ultrastructural analyses of zebrafish leucophores revealed cell-type specific chemical compositions, organelle configurations and genetic requirements. At the organismal level, we identified distinct physiological responses of leucophores during environmental background matching and we show that leucophore complement influences behavior. Together, our studies revealed new, independently arisen pigment cell types and mechanisms of fate acquisition in zebrafish, and illustrate how concerted analyses across hierarchical levels can provide insights into phenotypes and their evolution.
Project description:In zebrafish, there are interactions between black pigment cells (melanophores) and yellow pigment cells (xanthophores) for pigment-pattern formation. However, the detailed molecular mechanism of these interactions remains largely unknown. We used microarray for identifying the molecular basis of these interactions by comparing gene expression between melanophores and xanthophores.
Project description:Investigation of whole genome expression pattern of 60 and 72 hours post fertilization Danio Rerio embryos exposed to TMT and vehicle control
Project description:In zebrafish, there are interactions between black pigment cells (melanophores) and yellow pigment cells (xanthophores) for pigment-pattern formation. However, the detailed molecular mechanism of these interactions remains largely unknown. We used microarray for identifying the molecular basis of these interactions by comparing gene expression between melanophores and xanthophores. Zebrafish pigment cells were collected from adult-fish fins by centrifugal separation or using cell sorter. melanophores vs. xanthophores
Project description:Investigation of whole genome expression pattern of 24 hours post fertilization Danio rerio embryos exposed to bisphenol A, 17beta-estradiol, GSK4716, or 0.1% DMSO vehicle control
