Temporal dynamics of myelination in the zebrafish spinal cord

Abstract

Knowledge of the precise timing of myelination is critical to the success of zebrafish-based in vivo screening strategies for potential remyelination therapies. This study provides a systematic review of the timing of myelination in the zebrafish spinal cord and a critique of techniques by which it may be accurately assessed. The onset of myelination was found to be 3 days postfertilization (d.p.f.); earlier than previously reported. This coincided with the dorsal migration and differentiation of oligodendrocytes and the expression of myelin basic protein (Mbp) transcripts and protein. Our data suggests that immunohistochemistry with zebrafish-specific anti-Mbp from 3 d.p.f. is the optimal histological method for myelin visualization, while quantification of myelination is more reliably achieved by quantitative polymerase chain reaction (qPCR) for mbp from 5 d.p.f.. Transgenic fluorescent lines such as olig2:EGFP can be used to assess oligodendrocyte cell number at 3 d.p.f. and the development of new, more specific lines may enable real time visualization of myelin itself. Quantitative ultrastructural analysis revealed that the myelination of zebrafish axons is regulated according to axonal growth and not absolute axonal size. This study confirms the use of the zebrafish larvae as a versatile and efficient in vivo model of myelination and provides a platform on which future myelination screening studies can be based.

Altered Behavioral Performance and Live Imaging of Circuit-Specific Neural Deficiencies in a Zebrafish Model for Psychomotor Retardation

“…The expression of myelin-related genes is first detected at 2 dpf and the onset of myelination was reported to be at 3 dpf [41]. In 3 dpf embryos, olig2 was expressed mainly in precursor neural cells in the cerebellum, prethalamus, and spinal cord (Fig.…”

Bioconcentration, metabolism and neurotoxicity of the organophorous flame retardant 1,3-dichloro 2-propyl phosphate (TDCPP) to zebrafish

“…Both rabbit ¦Á1-tubulin antibody (Abcam, Cambridge, UK) and rabbit mbp (AnaSpec, Fremont, CA) have previously been verified as reactive and suitable for zebrafish studies (Thatcher et al 2008;Buckley et al 2010). After incubation with horseradish peroxidase-conjugated goat anti-rabbit IgG (1:50,000) for 2 h at room temperature, the signal was detected by enhanced chemiluminescence.…”

Bioconcentration and metabolism of BDE-209 in the presence of titanium dioxide nanoparticles and impact on the thyroid endocrine system and neuronal development in zebrafish larvae

“…The membrane was further blocked with 5% fat-free milk for 2 h in TBS (10 mM Tris, 150 mM NaCl, pH 8.0) and 0.1% Tween 20, before being incubated overnight at 4 C with primary antibodies against myelin basic protein (1:300), a1-tubulin (1:100) or b-actin (1:1000). Both rabbit a1-tubulin antibody (Abcam, Cambridge, UK) and rabbit myelin basic protein (AnaSpec, Fremont, CA) have previously been verified reactive and suitable for zebrafish studies (Buckley et al, 2010;Thatcher et al, 2008). After incubation with horseradish peroxidase-conjugated goat anti-rabbit IgG (1:50 000) for 2 h at room temperature, the signal was detected by enhanced chemiluminescence.…”