Biology subjects

Perry, K. J.

Publications and source records attributed to Perry, K. J..

3 recordsLinked to original sources

bioRxiv2022

A single amino acid change drives left- right asymmetry in Bilateria

Asymmetries are essential for proper organization and function of organ systems. Genetic studies in deuterostomes have shown signaling through the Nodal/Smad2 pathway plays a key, conserved role in the establishment of body asymmetries. While Nodal signaling is required for the establishment of left-right asymmetry (LRA) across bilaterian species, little is known about the regulation of Nodal signaling in spiralians. Here, we identified orthologs of the egf-cfc gene, a master regulator of the Nodal pathway in vertebrates, in several invertebrate species, the first evidence of its presence in non-deuterostomes. Our functional experiments indicate that despite being present, egf-cfc does not play a role in the establishment LRA in gastropods. However, experiments in zebrafish suggest that a single amino acid mutation in the egf-cfc gene in the deuterostome common ancestor was the necessary step in inducing a gain-of-function in LRA regulation. This study shows that that the egf-cfc gene likely appeared in the bilaterian stem lineage, before being adopted as a master mechanism to regulate the Nodal pathway and the establishment of LRA in deuterostomes.

developmental biology↗

bioRxiv2020

Single-cell analyses of the corneal epithelium: Unique cell types and gene expression profiles

Corneal Epithelial Stem Cells (CESCs) and their proliferative progeny, the Transit Amplifying Cells (TACs), are responsible for homeostasis and maintaining corneal transparency. Owing to our limited knowledge of cell fates and gene activity within the cornea, the search for unique markers to identify and isolate these cells remains crucial for ocular surface reconstruction. We performed single-cell RNA sequencing of corneal epithelial cells from stage 49-51 Xenopus larvae. We identified five main clusters with distinct molecular signatures, which represent apical, basal and keratocyte cell types as well as two discrete proliferative cell types in the bi-layered epithelium. Our data reveal several novel genes expressed in corneal cells and spatiotemporal changes in gene expression during corneal differentiation. Through gene regulatory network analysis, we identified key developmental gene regulons, which guide these different cell states. Our study offers a detailed atlas of single-cell transcriptomes in the frog corneal epithelium. In future, this work will be useful to elucidate the function of novel genes in corneal homeostasis, wound healing and cornea regeneration, which includes lens regeneration in Xenopus. SUMMARY STATEMENTThis study identifies cell types and transcriptional heterogeneity in the corneal epithelium that regulate its differentiation, and facilitates the search for corneal stem cell markers.

developmental biology↗

bioRxiv2018

FGF1 Promotes Xenopus laevis Lens Regeneration

BackgroundThe frog Xenopus laevis has notable regenerative capabilities, including that of the lens. The neural retina provides the factors that trigger lens regeneration from the cornea, but the identity of these factors is largely unknown. In contrast to the cornea, fibroblast growth factors FGF1, 8, and 9 are highly expressed within the retina, and are potential candidates for those factors. The purpose of this study is to determine whether specific FGF proteins can induce lens formation, and if perturbation of FGFR signaling inhibits lens regeneration.\n\nMethodsA novel cornea epithelial culture method was developed to investigate the sufficiency of FGFs in lens regeneration. Additionally, transgenic larvae expressing dominant negative FGFR1 were used to investigate the necessity of FGFR signaling in lens regeneration.\n\nResultsTreatment of cultured corneas with FGF1 induced lens regeneration in a dose-dependent manner, whereas treatment with FGF2, FGF8, or FGF9 did not result in significant lens regeneration. Inhibition of FGFR signaling decreased the lens regeneration rate for in vitro eye cultures.\n\nConclusionThe culture techniques developed here, and elsewhere, have provided reliable methods for examining the necessity of various factors that may be involved in lens regeneration. Based on the results demonstrated in this study, we found that FGF1 signaling and FGFR activation are key factors for lens regeneration in Xenopus.

developmental biology↗