Project description:Vertebrate vision is mediated by two kinds of photoreceptors, rods and cones, responsible for dim- and bright-light vision, respectively. Gene expression differences among cone subtypes remain poorly understood compared with rods. We generated single-cell transcriptome data using a droplet-based approach to reveal the extent of gene expression diversity among adult zebrafish photoreceptor subtypes. Populations of photoreceptor cells were enriched by using the transgenic zebrafish lines, Tg(rho:EGFP)ja2Tg and Tg(gnat2:EGFP)ja23Tg, which express GFP in rods and all cone subtypes, respectively. By analyzing the single-cell transcriptomes, we found that in addition to the four canonical zebrafish cone types (ultraviolet, blue, green and red), there exist subpopulations of green and red cones in the ventral retina that express red-shifted opsin paralogs (opn1mw4 and opn1lw1). This work lays a foundation for future studies aimed at understanding how molecular differences among cone subtypes affect photoreceptor function.
Project description:Molecular underpinnings of vertebrate retinal differentiation and maturation are poorly understood, particularly for non-mammalian species. We generated single-cell transcriptome data from the larval zebrafish retina and characterized gene expression diversity among photoreceptor subtypes and their progenitors.
Project description:Photoreceptor damage in adult mammals results in permanent cell loss and glial scarring in the retina. In contrast, adult zebrafish can regenerate photoreceptors following injury. By using a stable transgenic line in which GFP is driven by the cis-regulatory sequences of a glial specific marker gfap, Tg(gfap:GFP)mi2002, previous studies showed that Müller glia, the radial glial cells in the retina, proliferate after photoreceptor loss and give rise to neuronal progenitors that eventually differentiate into regenerated photoreceptors. To identify the molecular mechanisms that initiate this regenerative response, Müller glia were isolated from Tg(gfap:GFP)mi2002 fish during the early stages of regeneration after light lesion and gene expression profiles were generated by microarray analyses. Keywords: time course
Project description:Identifying the transcription factors required to specify photoreceptor subtypes is critical to understand the normal development of the retina and to inform cell-replacement therapies to restore vision. RNA-seq is a powerful way to identify novel genes expressed in particular cell subtypes. Although RNA-seq approaches have been used to identify genes differentially expressed between photoreceptor subtypes in many species, the limited transcriptome depth derived from single-cell techniques constitutes a barrier in the reliable detection of transcription factors. To obtain a deep, high-quality RNA-seq dataset from zebrafish photoreceptors, we manually collected pools of photoreceptors of a single subtype.
Project description:Photoreceptor damage in adult mammals results in permanent cell loss and glial scarring in the retina. In contrast, adult zebrafish can regenerate photoreceptors following injury. By using a stable transgenic line in which GFP is driven by the cis-regulatory sequences of a glial specific marker gfap, Tg(gfap:GFP)mi2002, previous studies showed that Müller glia, the radial glial cells in the retina, proliferate after photoreceptor loss and give rise to neuronal progenitors that eventually differentiate into regenerated photoreceptors. To identify the molecular mechanisms that initiate this regenerative response, Müller glia were isolated from Tg(gfap:GFP)mi2002 fish during the early stages of regeneration after light lesion and gene expression profiles were generated by microarray analyses. Keywords: time course Retinas were dissected from Tg(gfap:GFP)mi2002 zebrafish at 8, 16, 24, 36 hour post-lesion (hpl) and non-light-treated controls (0 hpl) and were dissociated by enzymatic digestion. GFP+ Müller glia were isolated by fluorescence-activated cell sorting (FACS) for RNA extraction and hybridization on Affymetrix microarrays. Independent hybridization of three biological replicates were performed for each time point.
Project description:To profile the diversity of cell types present in adult zebrafish synovial joints, we performed single-cell RNA sequencing of the uninjured adult jaw joint and identified multiple skeletal, connective tissue, and fibroblast subtypes, including a joint-specific periosteal population.
Project description:The signaling molecule retinoic acid (RA) regulates rod and cone photoreceptor fate, differentiation, and survival. The purpose of this study was to identify eye-specific genes controlled by RA during photoreceptor differentiation in the zebrafish. 6 samples; 3 replicates of 2 conditions