and beta III tubulin do not colocalise in PrP null neurons treated with HuPrP106-126. (A) Primary cortical neurons from PrP null mice were left untreated, or treated with 1 μM PMA + 5 μM A23187, or 40 μM HuPrP106-126 for 30 minutes. Images show a representative picture of two individual experiments. Scale bar: 50 μM. (B) Colocalisation of the two antibodies was measured by correlation. An overall average colocalisation of all results is shown. *P < 0.05.