Fig. 7. Decreased MAP1B and increased RND2 levels in axons of COUP-TFI-deficient primary neurons. (A-B'') Confocal images of primary hippocampal neurons after 24 hours in culture labelled with antibodies recognizing MAP1B and TAU. MAP1B and TAU staining overlap in the cell body and neurites in wild-type neurons (A-A''). Axonal MAP1B levels are clearly reduced in COUP-TFI^null mutants, as shown by the arrowheads in B and in a merged image (B''), whereas TAU fluorescence levels do not change (B'). (C) Quantification of TAU and MAB1P fluorescence in the cell body and in the axon via relative intensity measurement (see text for more details). (D-E'') Immunofluorescence of RND2 and TAU in primary neurons after 48 hours in culture. RND2 is restricted to the cell body close to where the axon emerges in wild-type neurons, but is upregulated and ectopically distributed along the whole length of NULL neurons, as indicated by arrowheads (E-E''). Scale bars: 20 µm. NULL, COUP-TFI^null neurons; WT, wild-type neurons.