Requirement of guanosine triphosphate-bound ran for signal-mediated nuclear protein export.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 9188526.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
A leucine-rich nuclear export signal (NES) allows rapid export of proteins from cell nuclei. Microinjection studies revealed a role for the guanosine triphosphatase (GTPase) Ran in NES-mediated export. Nuclear injection of a Ran mutant (Thr24 --> Asn) blocked protein export but not import, whereas depletion of the Ran nucleotide exchange factor RCC1 blocked protein import but not export. However, injection of Ran GTPase-activating protein (RanGAP) into RCC1-depleted cell nuclei inhibited export. Coinjection with Ran mutants insensitive to RanGAP prevented this inhibition. Therefore, NES-mediated protein export appears to require a Ran-GTP complex but does not require Ran-dependent GTP hydrolysis.
Medical subject headings
- Cell Cycle Proteins
- Cell Nucleus
- GTP Phosphohydrolases
- GTPase-Activating Proteins
- Guanine Nucleotide Exchange Factors
- Guanosine Triphosphate
- Nuclear Proteins