Development and Degeneration of Retinal Ganglion Cell Axons in Xenopus tropicalis.

Content Provider	Europe PMC
Author	Choi, Boyoon Kim, Hyeyoung Jang, Jungim Park, Sihyeon Jung, Hosung
Copyright Year	2022
Abstract	Neurons make long-distance connections via their axons, and the accuracy and stability of these connections are crucial for brain function. Research using various animal models showed that the molecular and cellular mechanisms underlying the assembly and maintenance of neuronal circuitry are highly conserved in vertebrates. Therefore, to gain a deeper understanding of brain development and maintenance, an efficient vertebrate model is required, where the axons of a defined neuronal cell type can be genetically manipulated and selectively visualized in vivo. Placental mammals pose an experimental challenge, as time-consuming breeding of genetically modified animals is required due to their in utero development. Xenopus laevis, the most commonly used amphibian model, offers comparative advantages, since their embryos ex utero during which embryological manipulations can be performed. However, the tetraploidy of the X. laevis genome makes them not ideal for genetic studies. Here, we use Xenopus tropicalis, a diploid amphibian species, to visualize axonal pathfinding and degeneration of a single central nervous system neuronal cell type, the retinal ganglion cell (RGC). First, we show that RGC axons follow the developmental trajectory previously described in X. laevis with a slightly different timeline. Second, we demonstrate that co-electroporation of DNA and/or oligonucleotides enables the visualization of gene function-altered RGC axons in an intact brain. Finally, using this method, we show that the axon-autonomous, Sarm1-dependent axon destruction program operates in X. tropicalis. Taken together, the present study demonstrates that the visual system of X. tropicalis is a highly efficient model to identify new molecular mechanisms underlying axon guidance and survival.
ISSN	10168478
Journal	Molecules and Cells
Volume Number	45
PubMed Central reference number	PMC9676988
Issue Number	11
PubMed reference number	36380734
e-ISSN	02191032
DOI	10.14348/molcells.2022.0081
Language	English
Publisher	Korean Society for Molecular and Cellular Biology
Publisher Date	2022-11-07
Access Restriction	Open
Rights License	This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-sa/3.0/ © The Korean Society for Molecular and Cellular Biology. All rights reserved.
Subject Keyword	axon degeneration axon guidance development Xenopus tropicalis
Content Type	Text
Resource Type	Article
Subject	Cell Biology Medicine Molecular Biology