The peptide HDEF as a new retention signal is necessary and sufficient to direct proteins to the endoplasmic reticulum

• Published in: FEBS letters Vol. 434; no. 3; pp. 377 - 381
• Main Authors: Kaletta, Karin, Kunze, Irene, Kunze, Gotthard, Köck, Margret
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 04.09.1998
• Subjects: Amino Acid Sequence; Base Sequence; Chitinase; DNA Primers; Endoplasmic Reticulum - metabolism; Endoplasmic reticulum and retention; Endoribonucleases - metabolism; Genes, Reporter; Heterologous expression; Lycopersicon esculentum - enzymology; Oligopeptides - chemistry; Oligopeptides - metabolism; Protein Sorting Signals - chemistry; Protein Sorting Signals - metabolism; Recombinant Fusion Proteins - genetics; Ribonuclease; Saccharomyces cerevisiae; Saccharomyces cerevisiae - metabolism; Tomato; Chitinase; Endoplasmic reticulum and retention; Ribonuclease; Tomato; Saccharomyces cerevisiae; Heterologous expression
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/S0014-5793(98)01013-8

The key feature of tomato RNase LX localised solely outside the vacuole is the C-terminal peptide HDEF which is very similar to known endoplasmic reticulum (ER) retention signals. For functional testing of the ER-targeting ability of HDEF, different constructs including the complete RNase LX, two truncated forms without HDEF and the truncated chitinase FB7-1ΔVTP C-terminally flanked by HDEF, were expressed in Saccharomyces cerevisiae. The majority of RNase and chitinase, both containing HDEF, accumulates within the ER. However, the truncated constructs without the peptide are released into the medium. We provide compelling evidence that peptide HDEF at the C-terminus of secretory plant proteins is a new ER retention signal in yeast and most likely in plants.