Role of rRAB22b, an oligodendrocyte protein, in regulation of transport of vesicles from trans Golgi to endocytic compartments.
Intracellular membrane trafficking plays an essential role in the biogenesis and maintenance of myelin. Members of the Rab protein family are important components of the systems that regulate intracellular vesicle transport. We examine the function of rRab22b, a novel rat Rab protein cloned from an oligodendrocyte cDNA library, by visualizing and identifying in living Hela cells the organelles that contain rRab22b. Our results show that rRab22b is present in the trans Golgi/TGN and endocytic compartments. Trafficking of membranes from trans Golgi to endocytic compartments takes place via small tubulo vesicular organelles containing rRab22b. The formation of vesicles in the trans Golgi also appears to be regulated by rRab22b. Additionally, our results suggest that rRab22b controls the transport of vesicles from the trans Golgi to endocytic compartments that localize in oligodendrocyte processes. That rRab22b is involved in the transport of certain proteins from trans Golgi to myelin is suggested by the evidence that certain proteins being targeted to the plasma membrane are first transported from trans Golgi to endocytic compartments.
Rodriguez-Gabin
A G
AG
Department of Neurology/Neuroscience, Albert Einstein College of Medicine, 1300 Morris Park Ave., Bronx, NY 10461, USA.
Cammer
M
M
Almazan
G
G
Charron
M
M
Larocca
J N
JN
D000595:Amino Acid Sequence / Q000502:physiology; D000818:Animals; D000831:Animals, Newborn; D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence / Q000502:physiology; D002451:Cell Compartmentation / Q000502:physiology; D002478:Cells, Cultured / Q000166:cytology / Q000378:metabolism; D002490:Central Nervous System / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D002540:Cerebral Cortex / Q000166:cytology / Q000254:growth & development / Q000378:metabolism; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry; D011992:Endosomes / Q000378:metabolism* / Q000648:ultrastructure; D006056:Golgi Apparatus / Q000378:metabolism* / Q000648:ultrastructure; D006367:HeLa Cells / Q000166:cytology / Q000378:metabolism; D006801:Humans; D007202:Indicators and Reagents / Q000378:metabolism; D008164:Luminescent Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D009154:Mutation / Q000502:physiology; D009836:Oligodendroglia / Q000166:cytology / Q000378:metabolism*; D015388:Organelles / Q000378:metabolism / Q000648:ultrastructure; D021381:Protein Transport / Q000502:physiology*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011993:Recombinant Fusion Proteins; D022161:Transport Vesicles / Q000378:metabolism* / Q000648:ultrastructure; D020691:rab GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*
D001426:Bacterial Proteins; D018076:DNA, Complementary; D007202:Indicators and Reagents; D008164:Luminescent Proteins; C484190:RAB31 protein, human; D012333:RNA, Messenger; C484189:Rab31 protein, rat; D011993:Recombinant Fusion Proteins; C054562:yellow fluorescent protein, Bacteria; D020691:rab GTP-Binding Proteins