Nuclear export of 5S rRNA-containing ribonucleoprotein complexes requires CRM1 and the RanGTPase cycle.
In Xenopus oocytes, 5S rRNA is exported out of the nucleus in the context of two ribonucleoprotein complexes (RNPs): complexed with transcription factor IIIA as the 7S RNP or as the 5S RNP with ribosomal protein L5. 5S rRNA-containing RNP export takes place at a slow rate in comparison to that of nuclear export signal-containing proteins and the U1 snRNP. Using oocyte microinjection assays we found that the export of 5S RNPs requires nuclear RanGTP and RanGTP hydrolysis and is leptomycin B-sensitive, indicating the process is mediated by the export receptor CRM1. A novel nuclear export signal motif is characterised in a region of L5 also possessing a nuclear import signal, thus identifying a shuttling domain for this protein. This same motif in L5 is found to be required for interaction with CRM1 in vitro and for export in vivo.
Murdoch
Kirstie
K
Institut für Biochemie und Molekulare Zellbiologie, Georg-August-Universität, Göttingen, Germany.
Loop
Susanne
S
Rudt
Falko
F
Pieler
Tomas
T
D021581:Active Transport, Cell Nucleus / Q000502:physiology*; D000595:Amino Acid Sequence / Q000235:genetics; D000818:Animals; D002467:Cell Nucleus / Q000201:enzymology*; D005057:Eukaryotic Cells / Q000201:enzymology*; D005260:Female; D006153:Guanosine Diphosphate / Q000235:genetics / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000235:genetics / Q000378:metabolism; D028884:Karyopherins / Q000235:genetics / Q000378:metabolism*; D009865:Oocytes; D017434:Protein Structure, Tertiary / Q000235:genetics; D012341:RNA, Ribosomal, 5S / Q000235:genetics / Q000378:metabolism*; D020733:RNA, Small Cytoplasmic / Q000235:genetics / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear; D012261:Ribonucleoproteins / Q000235:genetics / Q000378:metabolism*; D018271:Signal Recognition Particle / Q000235:genetics / Q000378:metabolism; D013997:Time Factors; D014982:Xenopus laevis; D020931:ran GTP-Binding Protein / Q000235:genetics / Q000378:metabolism*; D000097606:Exportin 1 Protein
D006153:Guanosine Diphosphate; D006160:Guanosine Triphosphate; D028884:Karyopherins; D012341:RNA, Ribosomal, 5S; D020733:RNA, Small Cytoplasmic; D018160:Receptors, Cytoplasmic and Nuclear; D012261:Ribonucleoproteins; D018271:Signal Recognition Particle; D020931:ran GTP-Binding Protein; D000097606:Exportin 1 Protein; C115990:7SL RNA