Neural receptor-linked protein @entity669 phosphatases (RPTPs) are required for guidance of motoneuron and photoreceptor growth cones in @entity238 . These phosphatases have not been implicated in growth cone responses to specific guidance cues, however, so it is unknown which aspects of axonal pathfinding are controlled by their activities. Three RPTPs, known as @entity34549 , @entity47972 , and @entity69041 , have been genetically characterized thus far. Here we report the isolation of mutations in the fourth neural RPTP, @entity69042 . The analysis of double mutant phenotypes shows that @entity69042 and @entity47972 are necessary for repulsion of growth cones from the midline of the embryonic central nervous system. Repulsion is thought to be triggered by binding of the secreted protein Slit, which is expressed by midline glia, to @entity39491 ( @entity39491 ) receptors on growth cones. @entity39491 repulsion is downregulated by the Commissureless ( @entity69043 ) protein, allowing axons to cross the midline. Here we show that the Rptp mutations genetically interact with @entity39491 , slit and @entity69043 . The nature of these interactions suggests that @entity69042 and @entity47972 are positive regulators of Slit/ @entity39491 repulsive signaling. We also show that elimination of all four neural RPTPs converts most noncrossing longitudinal pathways into commissures that cross the midline, indicating that @entity669 phosphorylation controls the manner in which growth cones respond to midline signals.

Receptor XXXX phosphatases regulate axon guidance across the midline of the @entity238 embryo.

@entity69042 :: ('32115(Tax:7227)', 'Gene') :: ['DPTP10D'] @entity69043 :: ('39717(Tax:7227)', 'Gene') :: ['Comm', 'comm'] @entity34549 :: ('35259(Tax:7227)', 'Gene') :: ['DLAR'] @entity39491 :: ('37603(Tax:7227)', 'Gene') :: ['robo', 'Robo', 'Roundabout'] @entity69041 :: ('43469(Tax:7227)', 'Gene') :: ['DPTP99A'] @entity47972 :: ('39443(Tax:7227)', 'Gene') :: ['DPTP69D'] @entity669 :: ('CHEBI:18186', 'Chemical') :: ['tyrosine'] @entity238 :: ('7227', 'Species') :: ['Drosophila']
@entity669 :: (CHEBI:18186,Chemical) :: ['tyrosine']
