Molecular characterization of the SUMO-1 modification of RanGAP1 and its role in nuclear envelope association
The mammalian guanosine triphosphate (GTP)ase-activating protein RanGAP1 is the first example of a protein covalently linked to the ubiquitin-related protein SUMO-1. Here we used peptide mapping, mass spectroscopy analysis, and mutagenesis to identify the nature of the link between RanGAP1 and SUMO-...
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| Main Authors: | , , |
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| Format: | Article (Journal) |
| Language: | English |
| Published: |
January 26, 1998
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| In: |
The journal of cell biology
Year: 1998, Volume: 140, Issue: 2, Pages: 259-270 |
| ISSN: | 1540-8140 |
| DOI: | 10.1083/jcb.140.2.259 |
| Online Access: | Verlag, kostenfrei, Volltext: https://doi.org/10.1083/jcb.140.2.259
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| Author Notes: | Rohit Mahajan, Larry Gerace, and Frauke Melchior |
| Summary: | The mammalian guanosine triphosphate (GTP)ase-activating protein RanGAP1 is the first example of a protein covalently linked to the ubiquitin-related protein SUMO-1. Here we used peptide mapping, mass spectroscopy analysis, and mutagenesis to identify the nature of the link between RanGAP1 and SUMO-1. SUMO-1 is linked to RanGAP1 via glycine 97, indicating that the last 4 amino acids of this 101- amino acid protein are proteolytically removed before its attachment to RanGAP1. Recombinant SUMO-1 lacking the last four amino acids is efficiently used for modification of RanGAP1 in vitro and of multiple unknown proteins in vivo. In contrast to most ubiquitinated proteins, only a single lysine residue (K526) in RanGAP1 can serve as the acceptor site for modification by SUMO-1. Modification of RanGAP1 with SUMO-1 leads to association of RanGAP1 with the nuclear envelope (NE), where it was previously shown to be required for nuclear protein import. Sufficient information for modification and targeting resides in a 25-kD domain of RanGAP1. RanGAP1-SUMO-1 remains stably associated with the NE during many cycles of in vitro import. This indicates that removal of RanGAP1 from the NE is not a required element of nuclear protein import and suggests that the reversible modification of RanGAP1 may have a regulatory role. |
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| Item Description: | Gesehen am 05.09.2023 |
| Physical Description: | Online Resource |
| ISSN: | 1540-8140 |
| DOI: | 10.1083/jcb.140.2.259 |