ZFIN ID: ZDB-FIG-210205-37
Marshall-Phelps et al., 2020 - Neuronal activity disrupts myelinated axon integrity in the absence of NKCC1b. The Journal of cell biology   219(7) Full text @ J. Cell Biol.
ADDITIONAL FIGURES
EXPRESSION / LABELING:
Genes:
Fish:
Anatomical Terms:
Stage: Day 5
PHENOTYPE:
Fish:
Observed In:
Stage Range: Day 5 to Day 6

Fig. 2 Disruption to NKCC1b leads to swelling of the periaxonal space, dysmyelination, and axonal disorganization. (A) Electron micrographs of high-pressure–frozen pLLn in control (left) and slc12a2bue58 mutant (right) at 5 dpf. slc12a2bue58 mutants show significant enlargement of the periaxonal space, highlighted in blue and enlarged axons (asterisk). Insets show a higher magnification to highlight the periaxonal space in controls and slc12a2bue58 mutants. White scale bar, 1 µm. Black scale bars, 50 nm. (B) Quantification of periaxonal area in control and slc12a2bue58 mutants (control 0.05 ± 0.02 µm2 vs. slc12a2bue58 4 ± 3.5 µm2, P = 0.0065). Error bars represent mean ± SD. A two-tailed Student’s t test was used to assess statistical significance. Each point represents an individual myelinated axon from three control and five slc12a2bue58 mutant animals. **, P < 0.01. (C) Quantification of the diameter of myelinated axons in control and slc12a2bue58 mutants. Bracket indicates axons in the mutant with greater than normal diameter. (D) Confocal images of live Tg(cntn1b:mCherry), Tg(mbp:EGFP-CAAX) double-transgenic control (left) and slc12a2bue58 mutant (right) animals at 5 dpf indicates axonal defasciculation and derangement of myelin. Scale bar, 10 µm. (E) Confocal images of individual mosaically labeled Schwann cells in control (top left panel) and slc12a2bue58 mutants (panels 1–5) highlighting the variable morphological manifestation of the mutant phenotype. Scale bar, 10 µm. Arrows point to regions of normal appearing myelin and arrowheads to dysmyelination. (F) Quantitation of mean Schwann cell diameter in maximum intensity projection images of single Schwann cells at 6 dpf (control 2.6 ± 0.4 µm vs. slc12a2bue58 4.3 ± 1.3 µm, P = 0.0003). Error bars represent mean ± SD. A two-tailed Student’s t test was used to assess statistical significance. Each point represents a single cell from 11 control and 10 slc12a2bue58 mutant animals. Scale bar, 10 µm. ***, P < 0.001. (G) Quantitation of mean Schwann cell length in maximum intensity projection images of single Schwann cells at 6 dpf (control 72.1 ± 15.7 µm vs. slc12a2bue58 54.7 ± 13.8 µm, P = 0.011). Error bars represent mean ± SD. A two-tailed Student’s t test was used to assess statistical significance. Each point represents a single cell from 11 control and 10 slc12a2bue58 mutant animals. *, P < 0.05.

Gene Expression Details
Gene Antibody Fish Conditions Stage Anatomy Assay
EGFP slc12a2lue58/ue58; ue2Tg; ue3Tg standard conditions Day 5 posterior lateral line myelin sheath IFL
ue2Tg; ue3Tg standard conditions Day 5 posterior lateral line myelin sheath IFL
mCherry slc12a2lue58/ue58; ue2Tg; ue3Tg standard conditions Day 5 posterior lateral line axon IFL
ue2Tg; ue3Tg standard conditions Day 5 posterior lateral line axon IFL
Antibody Labeling Details No data available
Phenotype Details
Fish Conditions Stage Phenotype
slc12a2lue58/ue58 standard conditions Day 5 posterior lateral line myelin sheath adaxonal region separated from posterior lateral line axon, abnormal
Day 5 posterior lateral line peripheral nervous system myelin maintenance decreased process quality, abnormal
Day 6 posterior lateral line myelinating Schwann cell increased diameter, abnormal
slc12a2lue58/ue58; ue2Tg; ue3Tg standard conditions Day 5 posterior lateral line axon defasciculated, abnormal
Day 5 posterior lateral line myelin sheath deformed, abnormal
Day 5 posterior lateral line peripheral nervous system myelin maintenance decreased process quality, abnormal
Acknowledgments:
ZFIN wishes to thank the journal The Journal of cell biology for permission to reproduce figures from this article. Please note that this material may be protected by copyright. Full text @ J. Cell Biol.