Figure 1. Co-distribution of anillin with myelin septins.

(A) Immunoblotting of myelin purified from the brains of wild type mice at P75 compared to brain lysates indicates that anillin (ANLN) is enriched in myelin similar to septin 8 variant 1 (SEPT8_v1). The same amount of protein was loaded. The myelin marker MOG and the axonal marker TUJ1 served as controls. Blot shows n = 2 mice per genotype representative of n = 3 mice per genotype. (B–C) Immunofluorescent signal of ANLN (green in B) and SEPT7 (green in C) extends longitudinally along axons identified by neurofilament-labelling (red in B–C). Additional ANLN-immunopositive puncta (asterisks in B) were not evidently associated with filamentous structures (arrowheads in B,C). The panels show maximal projections of confocal stacks and 3-dimensional reconstructions of longitudinally sectioned spinal cord of P75 WT mice. Images representative of three mice. (D) Immunoblotting of myelin purified from the brains of wild-type mice at P15, P18, P21 and P24 indicates that the abundance of ANLN in myelin increases with maturation. Myelin septins (SEPT2, SEPT4, SEPT7, SEPT8) and MAG served as control. Blot shows n = 1 mouse per timepoint. (E) Immunolabelling of longitudinally sectioned WT optic nerves detects ANLN (red) in proximity to SEPT8 (green); co-labeled structures (arrowheads) were seen occasionally at P21 and frequently at P28 but not at P15. TUJ1 served as axonal marker. Images representative of three experiments.

Figure 1—figure supplement 1. Co-labeling of ANLN and SEPT8 in various white matter tracts.

(A–B) Immunolabelling of coronal brain sections of WT mice at P75 detects ANLN (red) and SEPT8 (green) filaments (arrowheads) in the indicated white matter tracts. (A–A’) shows labelling in the fimbria. (A’), enlargement of the dashed square in (A). (B) shows labelling in the corpus callosum. MAG or neurofilaments (NF) were co-labelled as control. Images representative of three experiments.