Skip to main content
NCBI home page
The Journal of Cell Biology logoLink to The Journal of Cell Biology
. 1990 Aug 1;111(2):323–328. doi: 10.1083/jcb.111.2.323

Molecular dissection of the NH2-terminal signal/anchor sequence of rat dipeptidyl peptidase IV

PMCID: PMC2116214  PMID: 1974258

Abstract

Dipeptidyl peptidase IV (DPPIV) is a membrane glycoprotein with a type II orientation in the plasma membrane. As shown in a cell-free translation system, the amino-terminal 34 amino acids of rat DPPIV are involved in translocating nascent polypeptide across the membrane of microsomes and in anchoring the translocated polypeptide in the microsomal membrane. The amino-terminal sequence performing this dual function is composed of: a central hydrophobic core of 22 amino acid residues; 6 amino-terminal residues preceding the hydrophobic core (MKTPWK); and 6 residues following the hydrophobic core. The six residues preceding the hydrophobic core are exposed on the outside (cytoplasmic side) of the microsomal membrane. Site-directed mutagenesis studies show that deletion of this cytoplasmic domain, excluding the amino-terminal initiating methionine, does not affect translocation of nascent DPPIV polypeptide, but does affect significantly anchoring of the translocated polypeptide in the microsomal membrane. In contrast, changing the two cytoplasmic Lys to Glu residues or shortening of the hydrophobic core from 22 to 15 residues or converting the last 11e of the shortened hydrophobic core into Ala affects neither translocation across nor anchoring of the DPPIV polypeptide in the microsomal membrane. These and other structural features of the DPPIV amino-terminal signal-anchor sequences are discussed along with other types of sequences for their role in targeting nascent polypeptides to the RER.

Full Text

The Full Text of this article is available as a PDF (1.0 MB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Blobel G. Intracellular protein topogenesis. Proc Natl Acad Sci U S A. 1980 Mar;77(3):1496–1500. doi: 10.1073/pnas.77.3.1496. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bos T. J., Davis A. R., Nayak D. P. NH2-terminal hydrophobic region of influenza virus neuraminidase provides the signal function in translocation. Proc Natl Acad Sci U S A. 1984 Apr;81(8):2327–2331. doi: 10.1073/pnas.81.8.2327. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Friedlander M., Blobel G. Bovine opsin has more than one signal sequence. 1985 Nov 28-Dec 4Nature. 318(6044):338–343. doi: 10.1038/318338a0. [DOI] [PubMed] [Google Scholar]
  4. Gilmore R., Walter P., Blobel G. Protein translocation across the endoplasmic reticulum. II. Isolation and characterization of the signal recognition particle receptor. J Cell Biol. 1982 Nov;95(2 Pt 1):470–477. doi: 10.1083/jcb.95.2.470. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Haeuptle M. T., Flint N., Gough N. M., Dobberstein B. A tripartite structure of the signals that determine protein insertion into the endoplasmic reticulum membrane. J Cell Biol. 1989 Apr;108(4):1227–1236. doi: 10.1083/jcb.108.4.1227. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Holland E. C., Drickamer K. Signal recognition particle mediates the insertion of a transmembrane protein which has a cytoplasmic NH2 terminus. J Biol Chem. 1986 Jan 25;261(3):1286–1292. [PubMed] [Google Scholar]
  7. Hong W. J., Doyle D. Membrane orientation of rat gp110 as studied by in vitro translation. J Biol Chem. 1988 Nov 15;263(32):16892–16898. [PubMed] [Google Scholar]
  8. Hong W. J., Petell J. K., Swank D., Sanford J., Hixson D. C., Doyle D. Expression of dipeptidyl peptidase IV in rat tissues is mainly regulated at the mRNA levels. Exp Cell Res. 1989 May;182(1):256–266. doi: 10.1016/0014-4827(89)90296-6. [DOI] [PubMed] [Google Scholar]
  9. Hong W., Doyle D. cDNA cloning for a bile canaliculus domain-specific membrane glycoprotein of rat hepatocytes. Proc Natl Acad Sci U S A. 1987 Nov;84(22):7962–7966. doi: 10.1073/pnas.84.22.7962. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Hunziker W., Spiess M., Semenza G., Lodish H. F. The sucrase-isomaltase complex: primary structure, membrane-orientation, and evolution of a stalked, intrinsic brush border protein. Cell. 1986 Jul 18;46(2):227–234. doi: 10.1016/0092-8674(86)90739-7. [DOI] [PubMed] [Google Scholar]
  11. Laperche Y., Bulle F., Aissani T., Chobert M. N., Aggerbeck M., Hanoune J., Guellaën G. Molecular cloning and nucleotide sequence of rat kidney gamma-glutamyl transpeptidase cDNA. Proc Natl Acad Sci U S A. 1986 Feb;83(4):937–941. doi: 10.1073/pnas.83.4.937. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Lipp J., Dobberstein B. The membrane-spanning segment of invariant chain (I gamma) contains a potentially cleavable signal sequence. Cell. 1986 Sep 26;46(7):1103–1112. doi: 10.1016/0092-8674(86)90710-5. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Monier S., Van Luc P., Kreibich G., Sabatini D. D., Adesnik M. Signals for the incorporation and orientation of cytochrome P450 in the endoplasmic reticulum membrane. J Cell Biol. 1988 Aug;107(2):457–470. doi: 10.1083/jcb.107.2.457. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Olsen J., Cowell G. M., Kønigshøfer E., Danielsen E. M., Møller J., Laustsen L., Hansen O. C., Welinder K. G., Engberg J., Hunziker W. Complete amino acid sequence of human intestinal aminopeptidase N as deduced from cloned cDNA. FEBS Lett. 1988 Oct 10;238(2):307–314. doi: 10.1016/0014-5793(88)80502-7. [DOI] [PubMed] [Google Scholar]
  15. Sabatini D. D., Kreibich G., Morimoto T., Adesnik M. Mechanisms for the incorporation of proteins in membranes and organelles. J Cell Biol. 1982 Jan;92(1):1–22. doi: 10.1083/jcb.92.1.1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Schmid S. R., Spiess M. Deletion of the amino-terminal domain of asialoglycoprotein receptor H1 allows cleavage of the internal signal sequence. J Biol Chem. 1988 Nov 15;263(32):16886–16891. [PubMed] [Google Scholar]
  17. Shelness G. S., Kanwar Y. S., Blobel G. cDNA-derived primary structure of the glycoprotein component of canine microsomal signal peptidase complex. J Biol Chem. 1988 Nov 15;263(32):17063–17070. [PubMed] [Google Scholar]
  18. Sivasubramanian N., Nayak D. P. Mutational analysis of the signal-anchor domain of influenza virus neuraminidase. Proc Natl Acad Sci U S A. 1987 Jan;84(1):1–5. doi: 10.1073/pnas.84.1.1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Spiess M., Lodish H. F. An internal signal sequence: the asialoglycoprotein receptor membrane anchor. Cell. 1986 Jan 17;44(1):177–185. doi: 10.1016/0092-8674(86)90496-4. [DOI] [PubMed] [Google Scholar]
  20. Szczesna-Skorupa E., Browne N., Mead D., Kemper B. Positive charges at the NH2 terminus convert the membrane-anchor signal peptide of cytochrome P-450 to a secretory signal peptide. Proc Natl Acad Sci U S A. 1988 Feb;85(3):738–742. doi: 10.1073/pnas.85.3.738. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Szczesna-Skorupa E., Kemper B. NH2-terminal substitutions of basic amino acids induce translocation across the microsomal membrane and glycosylation of rabbit cytochrome P450IIC2. J Cell Biol. 1989 Apr;108(4):1237–1243. doi: 10.1083/jcb.108.4.1237. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Walter P., Blobel G. Signal recognition particle contains a 7S RNA essential for protein translocation across the endoplasmic reticulum. Nature. 1982 Oct 21;299(5885):691–698. doi: 10.1038/299691a0. [DOI] [PubMed] [Google Scholar]
  23. Watt V. M., Yip C. C. Amino acid sequence deduced from a rat kidney cDNA suggests it encodes the Zn-peptidase aminopeptidase N. J Biol Chem. 1989 Apr 5;264(10):5480–5487. [PubMed] [Google Scholar]
  24. Wickner W. T., Lodish H. F. Multiple mechanisms of protein insertion into and across membranes. Science. 1985 Oct 25;230(4724):400–407. doi: 10.1126/science.4048938. [DOI] [PubMed] [Google Scholar]
  25. Zerial M., Melancon P., Schneider C., Garoff H. The transmembrane segment of the human transferrin receptor functions as a signal peptide. EMBO J. 1986 Jul;5(7):1543–1550. doi: 10.1002/j.1460-2075.1986.tb04395.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. von Heijne G. Patterns of amino acids near signal-sequence cleavage sites. Eur J Biochem. 1983 Jun 1;133(1):17–21. doi: 10.1111/j.1432-1033.1983.tb07424.x. [DOI] [PubMed] [Google Scholar]

Articles from The Journal of Cell Biology are provided here courtesy of The Rockefeller University Press

RESOURCES