Receptor tyrosine phosphatases in axon growth and guidance

Receptor-like protein tyrosine phosphatases (RPTPs) continue to emerge as i mportant signalling molecules in axons and their growth cones. Recent findi ngs show that Drosophila RPTPs play key roles in guiding retinal axons and in preventing midline crossing of longitudinal axons. Vertebrate RPTPs are now implicated in controlling axon outgrowth, and preliminary evidence sugg ests that they too may influence axon guidance.