Figure 4.

Increased and less regular nodal spacing along individual axons in nfasca^Δ28/Δ28 mutants

(A) Targeting strategy and genetic lesion in nfasca^Δ28/Δ28 mutants.

(B) Immunohistochemistry against Nfasca on spinal cord cross-sections in adult heterozygous and homozygous nfasca^Δ28/Δ28 animals. Scale bar, 10 μm. (B′) Cross-sectional views around a node of Ranvier at different z positions in a heterozygous nfasca^Δ28/+ animal. Scale bar, 1 μm.

(C) Overviews of the spinal cord in full transgenic myelin reporter lines. Arrowheads highlight gaps between adjacent myelin sheaths. Scale bar, 20 μm.

(D and E) Close-up views showing single nodes of Ranvier marked with EYFP-cntn1a and EYFP-NaV-II-III in full transgenic myelin reporter lines. Scale bar, 5 μm.

(F) Reconstructions of two CoPA neurons and their node of Ranvier positions (arrowheads) from wild type and nfasca^Δ28/Δ28 mutant animals. Scale bar, 50 μm.

(G) Average internodal distances along single axons per axon in wild type, nfasca^Δ28/Δ28, and nfasca^Δ28/Δ28 re-expressing Nfasca-EYFP in single axons. Median with IQR (Brown-Forsythe ANOVA with multiple comparisons); n = 9/4 (wild type), 10/8 (nfasca^Δ28/Δ28), and 13/4 (nfasca^Δ28/Δ28 rescue) animals/technical replicates.

(G′–G‴) Maximum (G′), minimum (G″), and range (G‴) of internodal distances per axon as quantified in (G). Median with IQR; Brown-Forsythe ANOVA with multiple comparisons for (G′ and G‴), Kruskal-Wallis test with multiple comparisons for (G″).

See also Figure S4 for supporting information.