Rab-mediated vesicular transport is required for neuronal positioning in the developing Drosophila visual system.
BACKGROUND
The establishment of tissue architecture in the nervous system requires the proper migration and positioning of newly born neurons during embryonic development. Defects in nuclear translocation, a key process in neuronal positioning, are associated with brain diseases such as lissencephaly in humans. Accumulated evidence suggests that the molecular mechanisms controlling neuronal movement are conserved throughout evolution. While the initial events of neuronal migration have been extensively studied, less is known about the molecular details underlying the establishment of neuronal architecture after initial migration.


RESULTS
In a search for novel players in the control of photoreceptor (R cell) positioning in the developing fly visual system, we found that misexpression of the RabGAP RN-Tre disrupted the apical localization of R-cell nuclei. RN-Tre interacts with Rab5 and Rab11 in the fly eye. Genetic analysis shows that Rab5, Shi and Rab11 are required for maintaining apical localization of R-cell nuclei.


CONCLUSIONS
We propose that Rab5, Shi and Rab11 function together in a vesicular transport pathway for regulating R-cell positioning in the developing eye.
Houalla
Tarek
T
McGill Centre for Research in Neuroscience, Department of Neurology and Neurosurgery, McGill University Health Centre, 1650 Cedar Avenue, Montreal, Quebec H3G 1A4, Canada.
Shi
Lei
L
van Meyel
Donald J
DJ
Rao
Yong
Y
D000818:Animals; D001692:Biological Transport / Q000502:physiology; D002467:Cell Nucleus / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000033:anatomy & histology* / Q000196:embryology* / Q000235:genetics; D034281:Dynamins / Q000235:genetics / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D009024:Morphogenesis; D016296:Mutagenesis; D009474:Neurons / Q000166:cytology / Q000502:physiology*; D010641:Phenotype; D017956:Photoreceptor Cells, Invertebrate / Q000166:cytology / Q000502:physiology; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D020691:rab GTP-Binding Proteins / Q000378:metabolism*; D020696:rab5 GTP-Binding Proteins / Q000378:metabolism*; D000099193:rab11 GTP-Binding Proteins
D029721:Drosophila Proteins; D034281:Dynamins; D011993:Recombinant Fusion Proteins; D020691:rab GTP-Binding Proteins; D020696:rab5 GTP-Binding Proteins; D000099193:rab11 GTP-Binding Proteins; C439628:shi protein, Drosophila