NESbase version 1.0: a database of nuclear export signals

Nucleic Acids Res. 2003 Jan 1;31(1):393-6. doi: 10.1093/nar/gkg101.


Protein export from the nucleus is often mediated by a Leucine-rich Nuclear Export Signal (NES). NESbase is a database of experimentally validated Leucine-rich NESs curated from literature. These signals are not annotated in databases such as SWISS-PROT, PIR or PROSITE. Each NESbase entry contains information of whether NES was shown to be necessary and/or sufficient for export, and whether the export was shown to be mediated by the export receptor CRM1. The compiled information was used to make a sequence logo of the Leucine-rich NESs, displaying the conservation of amino acids within a window of 25 residues. Surprisingly, only 36% of the sequences used for the logo fit the widely accepted NES consensus L-x(2,3)-[LIVFM]-x(2,3)-L-x-[LI]. The database is available online at

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Active Transport, Cell Nucleus*
  • Amino Acid Motifs
  • Animals
  • Conserved Sequence
  • Databases, Protein*
  • Leucine / chemistry
  • Proteins / chemistry*
  • Proteins / metabolism
  • Sequence Alignment


  • Proteins
  • Leucine