Fig. 1: An in vivo intact animal system to study AIS function in neuronal polarity.
From: Endocytosis in the axon initial segment maintains neuronal polarity
a, Schematic of C. elegans PVD and DA9 neurons. 1°, primary; 4°, quaternary. b, Localization of the myristoylated GFP membrane marker in the wild-type PVD neuron. Scale bar, 50 µm. c, Cell-specific endogenous labelling of the long isoform of UNC-44 (UNC-44L–FLPon–GFP) using flippase-mediated recombination. Scale bar, 5 µm. d, Patronin-1–tdTomato localization in the PVD neuron. Scale bar, 10 µm. e, Quantification of UNC-44L and patronin-1 in PVD neuronal domains. AU, arbitrary units. f, Schematic of PVD neuronal domains. g, Rat NF-186 localization in the PVD neuron. Scale bar, 5 µm. h, Rat NF-186(FIGQD) localization in the PVD neuron. Scale bar, 5 µm. i, Average fluorescence of rat wild-type and mutant NF-186 proteins in PVD neuronal domains. j, Localization of a myristoylated GFP membrane marker of the PVD neuron in dma-1(lof) C. elegans animals. Scale bar, 50 µm. k,l, Cell-specific endogenous labelling (k) and polarity index (l) of DMA-1–FLPon–GFP in C. elegans animals. Scale bar, 10 µm. m,n, The axonal region of C. elegans animals expressing endogenous (m) or overexpressed (n) DMA-1–GFP. The same imaging conditions and formatting were used in both panels. Scale bars, 5 µm. Red arrows indicate aberrant axonal branches. o, Mean normalized GFP fluorescence in the axon of C. elegans animals described in m,n. p, Escape behaviour in C. elegans animals in response to a harsh touch stimulus. C. elegans animals carrying mutations in degt-1 and mec-3, which encode a DEG/ENaC channel and a homeobox transcription factor that controls the differentiation of touch receptor neurons, respectively, were included as control animals with known behavioural defects. Data are shown as mean ± s.e.m. n represents the number of individual animals. e,i One-way ANOVA with Dunnett’s test. o, Two-tailed unpaired t-test with Welch’s correction. p, Two-tailed unpaired t-test.
