Efficiency and diversity of protein localization by random signal sequences.
Three randomly derived sequences that can substitute for the signal peptide of Saccharomyces cerevisiae invertase were tested for the efficiency with which they can translocate invertase or beta-galactosidase into the endoplasmic reticulum. The rate of translocation, as measured by glycosylation, was estimated in pulse-chase experiments to be less than 6 min. When fused to beta-galactosidase, these peptides, like the normal invertase signal sequence, direct the hybrid protein to a perinuclear region, consistent with localization to the endoplasmic reticulum. The diversity of function of random peptides was studied further by immunofluorescence localization of proteins fused to 28 random sequences: 4 directed the hybrid to the endoplasmic reticulum, 3 directed it to the mitochondria, and 1 directed it to the nucleus.
Kaiser
C A
CA
Department of Biology, Massachusetts Institute of Technology, Cambridge 02139.
Botstein
D
D
D000595:Amino Acid Sequence; D001483:Base Sequence; D004247:DNA / Q000235:genetics; D004251:DNA Transposable Elements; D005455:Fluorescent Antibody Technique; D005696:Galactosidases / Q000235:genetics*; D015723:Gene Library; D006026:Glycoside Hydrolases / Q000032:analysis / Q000235:genetics*; D006031:Glycosylation; D006801:Humans; D008969:Molecular Sequence Data; D010957:Plasmids; D011499:Protein Processing, Post-Translational; D021382:Protein Sorting Signals / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000032:analysis; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics*; D012689:Sequence Homology, Nucleic Acid; D043324:beta-Fructofuranosidase; D001616:beta-Galactosidase / Q000032:analysis / Q000235:genetics*
D004251:DNA Transposable Elements; D021382:Protein Sorting Signals; D011993:Recombinant Fusion Proteins; D004247:DNA; D005696:Galactosidases; D006026:Glycoside Hydrolases; D001616:beta-Galactosidase; D043324:beta-Fructofuranosidase