A EUKARYOTIC EXPRESSION VECTOR FOR THE STUDY OF NUCLEAR-LOCALIZATION SIGNALS

We describe a new vector designed to produce beta-galactosidase fusion proteins which can be used to assess subcellular localization of targ et peptide fragments or proteins in eukaryotic cells. The vector was c onstructed in such a way as to produce the peptide of interest in fusi on via a short linker of proline residues to the N terminus of the rep orter protein. Efficiency of the transport machinery is optimized usin g this particular protein fusion construction. This vector has potenti al uses for readily testing putative nuclear localization sequences an d identifying their crucial amino-acid residues.