C-terminal sequences can inhibit the insertion of membrane proteins into the endoplasmic reticulum of Saccharomyces cerevisiae

Mol Cell Biol. 1992 Jan;12(1):276-82. doi: 10.1128/mcb.12.1.276-282.1992.

Abstract

We have constructed three gene fusions that encode portions of a membrane protein, arginine permease, fused to a reporter domain, the cytoplasmic enzyme histidinol dehydrogenase (HD), located at the C-terminal end. These fusion proteins contain at least one of the internal signal sequences of arginine permease. When the fusion proteins were expressed in Saccharomyces cerevisiae and inserted into the endoplasmic reticulum (ER), two of the fusion proteins placed HD on the luminal side of the ER membrane, but only when a piece of DNA encoding a spacer protein segment was inserted into the fusion joint. The third fusion protein, with or without the spacer included, placed HD on the cytoplasmic side of the membrane. These results suggest that (i) sequences C-terminal to the internal signal sequence can inhibit membrane insertion and (ii) HD requires a preceding spacer segment to be translocated across the ER membrane.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Alcohol Oxidoreductases / genetics
  • Alcohol Oxidoreductases / metabolism
  • Amino Acid Sequence
  • Amino Acid Transport Systems*
  • Amino Acid Transport Systems, Basic
  • Base Sequence
  • Biological Transport
  • Cloning, Molecular
  • DNA, Fungal
  • Endoplasmic Reticulum / metabolism*
  • Enzyme Stability
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Membrane Transport Proteins / genetics
  • Membrane Transport Proteins / metabolism
  • Molecular Sequence Data
  • Precipitin Tests
  • Protein Sorting Signals / genetics
  • Protein Sorting Signals / metabolism
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Sequence Alignment

Substances

  • Amino Acid Transport Systems
  • Amino Acid Transport Systems, Basic
  • DNA, Fungal
  • Membrane Proteins
  • Membrane Transport Proteins
  • Protein Sorting Signals
  • Recombinant Fusion Proteins
  • arginine permease
  • Alcohol Oxidoreductases
  • histidinol dehydrogenase