The transient axonal glycoprotein-1 (TAG-1)/contactin-associated protein-like 2 (Caspr2) complex is not required for voltage-gated potassium (Kv)1 channels expression at the axon initial segment (AIS) and juxtapara (JXP)-AIS. Triple immunostaining of ankyrin G (AnkG) (A, D), Kv1.1 (B, E) and Caspr2 (C, F) in motor neurons (MNs) labeled with the anti-Peripherin antibody (data not shown), in wild-type (WT) (A-C) and TAG-1-/- (D-F) mice. Inset in (E): Mean Kv1.1 immunofluorescence intensity at the AIS and JXP-AIS in WT and KO mice. Brackets indicate Kv1.1+ and Caspr2+ domains in the AIS and JXP-AIS. Scale bar = 5 μm.