Diverse effects of the guanine nucleotide exchange factor RCC1 on RNA transport.
Transport of RNAs within nuclei and through nuclear pore complexes (NPCs) are essential, but poorly understood, steps in gene expression. In experiments with mammalian cells, RCC1, the abundant nuclear guanine nucleotide exchange factor for the guanosine triphosphatase Ran/TC4, was shown to be required for nucleocytoplasmic transport of precursors of spliceosomal small nuclear RNAs (snRNAs), intranuclear transport of U3 snRNA, and processing of ribosomal RNAs, but not for export of transfer RNAs. It is proposed that guanosine triphosphate (GTP)-bound Ran/TC4 associates with ribonucleoprotein particles (RNPs) during intranuclear movement, and that GTP hydrolysis promotes deposition of RNPs at targeted sites such as NPCs or nucleoli.
Cheng
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Department of Biomolecular Chemistry, University of Wisconsin School of Medicine, Madison 53706.
Dahlberg
J E
JE
Lund
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E
D001692:Biological Transport / Q000502:physiology; D018797:Cell Cycle Proteins; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000502:physiology*; D020662:Guanine Nucleotide Exchange Factors; D006160:Guanosine Triphosphate / Q000378:metabolism; D008745:Methylation; D009687:Nuclear Proteins / Q000378:metabolism / Q000502:physiology*; D012313:RNA / Q000378:metabolism*; D012322:RNA Precursors / Q000378:metabolism; D012335:RNA, Ribosomal / Q000378:metabolism; D012342:RNA, Small Nuclear / Q000378:metabolism; D012343:RNA, Transfer / Q000378:metabolism; D017381:Spliceosomes / Q000378:metabolism; D020931:ran GTP-Binding Protein
D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D020662:Guanine Nucleotide Exchange Factors; D009687:Nuclear Proteins; D012322:RNA Precursors; D012335:RNA, Ribosomal; D012342:RNA, Small Nuclear; D012313:RNA; D006160:Guanosine Triphosphate; D012343:RNA, Transfer; D020931:ran GTP-Binding Protein