The slit receptor Rig-1/Robo3 controls midline crossing by hindbrain precerebellar neurons and axons.
During development, precerebellar neurons migrate dorsoventrally from the rhombic lip to the floor plate. Some of these neurons cross the midline while others stop. We have identified a role for the slit receptor Rig-1/Robo3 in directing this process. During their tangential migration, neurons of all major hindbrain precerebellar nuclei express high levels of Rig-1 mRNA. Rig-1 expression is rapidly downregulated as their leading process crosses the floor plate. Interestingly, most precerebellar nuclei do not develop normally in Rig-1-deficient mice, as they fail to cross the midline. In addition, inferior olivary neurons, which normally send axons into the contralateral cerebellum, project ipsilaterally in Rig-1 mutant mice. Similarly, neurons of the lateral reticular nucleus and basilar pons are unable to migrate across the floor plate and instead remain ipsilateral. These results demonstrate that Rig-1 controls the ability of both precerebellar neuron cell bodies and their axons to cross the midline.
Marillat
Valérie
V
CNRS UMR7102, Université Paris 6, Bâtiment B, Case 12, 9 Quai Saint-Bernard, 75005 Paris, France.
Sabatier
Christelle
C
Failli
Vieri
V
Matsunaga
Eiji
E
Sotelo
Constantino
C
Tessier-Lavigne
Marc
M
Chédotal
Alain
A
D000818:Animals; D002454:Cell Differentiation / Q000235:genetics; D002531:Cerebellum / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D005333:Fetus; D007839:Functional Laterality / Q000235:genetics; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D020439:Growth Cones / Q000378:metabolism* / Q000648:ultrastructure; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D009154:Mutation / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D009434:Neural Pathways / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D009847:Olivary Nucleus / Q000166:cytology / Q000196:embryology / Q000378:metabolism; D011149:Pons / Q000166:cytology / Q000196:embryology / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011956:Receptors, Cell Surface; D012249:Rhombencephalon / Q000166:cytology / Q000196:embryology* / Q000378:metabolism; D000097905:Roundabout Proteins
D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; C118348:Robo3 protein, mouse; D000097905:Roundabout Proteins; C120010:Slit1 protein, mouse