Developmental and Injury-induced Changes in DNA Methylation in Regenerative versus Non-regenerative Regions of the Vertebrate Central Nervous System.

Background: Because some of its CNS neurons (e.g., retinal ganglion cells after optic nerve crush (ONC)) regenerate axons throughout life, whereas others (e.

Neurophysiological and Behavioral Analysis in .

Because of its resilience to hypoxia and trauma, the frog has long been a favored preparation of neurophysiologists. Its use has led to the discovery of many fundamental properties of neurons and neural circuits. Neurophysiologists were originally attracted to embryos, tadpoles, and frogs because of their ready availability, their external development, and the anatomical accessibility and relatively simple neural circuitry of the visual, locomotory, and vocalization systems.

Comparative gene expression profiling between optic nerve and spinal cord injury in Xenopus laevis reveals a core set of genes inherent in successful regeneration of vertebrate central nervous system axons.

Background: The South African claw-toed frog, Xenopus laevis, is uniquely suited for studying differences between regenerative and non-regenerative responses to CNS injury within the same organism, because some CNS neurons (e.g., retinal ganglion cells after optic nerve crush (ONC)) regenerate axons throughout life, whereas others (e.

Comparisons of SOCS mRNA and protein levels in Xenopus provide insights into optic nerve regenerative success.

In vertebrates from fishes to mammals, optic nerve injury induces increased expression ofSuppressor of Cytokine Signaling 3(SOCS3) mRNA, a modulator of cytokine signaling that is known to inhibit CNS axon regeneration. Unlike amniotes, however, anamniotes successfully regenerate optic axons, despite this increase. To address this seeming paradox, we examined the SOCS3 response to optic nerve injury in the frog,Xenopus laevis, at both the mRNA and protein levels.

Tracing Central Nervous System Axon Regeneration in .

Axonal tracing allows visualizing connectivity between neurons, providing useful information about structure, neuronal location, and function of the nervous system. Identifying regenerating axons and their neuron cell bodies present the particular challenges of labeling the projections of interest while unambiguously demonstrating regrowth of those axons that have been damaged. In the developing brain, an additional labeling challenge arises, as new connections are being made throughout the duration of an experiment.