Overcoming the Refractory Expression of Secreted Recombinant Proteins in Mammalian Cells through Modification of the Signal Peptide and Adjacent Amino Acids.

The expression and subsequent purification of mammalian recombinant proteins is of critical importance to many areas of biological science. To maintain the appropriate tertiary structure and post-translational modifications of such proteins, transient mammalian expression systems are often adopted....

Full description

Saved in:
Bibliographic Details
Main Authors: Gülin Güler-Gane, Sara Kidd, Sudharsan Sridharan, Tristan J Vaughan, Trevor C I Wilkinson, Natalie J Tigue
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2016-01-01
Series:PLoS ONE
Online Access:https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0155340&type=printable
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850189122785771520
author Gülin Güler-Gane
Sara Kidd
Sudharsan Sridharan
Tristan J Vaughan
Trevor C I Wilkinson
Natalie J Tigue
author_facet Gülin Güler-Gane
Sara Kidd
Sudharsan Sridharan
Tristan J Vaughan
Trevor C I Wilkinson
Natalie J Tigue
author_sort Gülin Güler-Gane
collection DOAJ
description The expression and subsequent purification of mammalian recombinant proteins is of critical importance to many areas of biological science. To maintain the appropriate tertiary structure and post-translational modifications of such proteins, transient mammalian expression systems are often adopted. The successful utilisation of these systems is, however, not always forthcoming and some recombinant proteins prove refractory to expression in mammalian hosts. In this study we focussed on the role of different N-terminal signal peptides and residues immediately downstream, in influencing the level of secreted recombinant protein obtained from suspension HEK293 cells. Using secreted alkaline phosphatase (SEAP) as a model protein, we identified that the +1/+2 downstream residues flanking a heterologous signal peptide significantly affect secreted levels. By incorporating these findings we conducted a comparison of different signal peptide sequences and identified the most productive as secrecon, a computationally-designed sequence. Importantly, in the context of the secrecon signal peptide and SEAP, we also demonstrated a clear preference for specific amino acid residues at the +1 position (e.g. alanine), and a detrimental effect of others (cysteine, proline, tyrosine and glutamine). When proteins that naturally contain these "undesirable" residues at the +1 position were expressed with their native signal peptide, the heterologous secrecon signal peptide, or secrecon with an additional alanine at the +1 or +1 and +2 position, the level of expression differed significantly and in an unpredictable manner. For each protein, however, at least one of the panel of signal peptide/adjacent amino acid combinations enabled successful recombinant expression. In this study, we highlight the important interplay between a signal peptide and its adjacent amino acids in enabling protein expression, and we describe a strategy that could enable recombinant proteins that have so far proved refractory to expression in HEK293 cells, to be produced in sufficient quantities to answer important biological questions.
format Article
id doaj-art-163661b1c73d4297a6385e8b932d0c2e
institution OA Journals
issn 1932-6203
language English
publishDate 2016-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj-art-163661b1c73d4297a6385e8b932d0c2e2025-08-20T02:15:41ZengPublic Library of Science (PLoS)PLoS ONE1932-62032016-01-01115e015534010.1371/journal.pone.0155340Overcoming the Refractory Expression of Secreted Recombinant Proteins in Mammalian Cells through Modification of the Signal Peptide and Adjacent Amino Acids.Gülin Güler-GaneSara KiddSudharsan SridharanTristan J VaughanTrevor C I WilkinsonNatalie J TigueThe expression and subsequent purification of mammalian recombinant proteins is of critical importance to many areas of biological science. To maintain the appropriate tertiary structure and post-translational modifications of such proteins, transient mammalian expression systems are often adopted. The successful utilisation of these systems is, however, not always forthcoming and some recombinant proteins prove refractory to expression in mammalian hosts. In this study we focussed on the role of different N-terminal signal peptides and residues immediately downstream, in influencing the level of secreted recombinant protein obtained from suspension HEK293 cells. Using secreted alkaline phosphatase (SEAP) as a model protein, we identified that the +1/+2 downstream residues flanking a heterologous signal peptide significantly affect secreted levels. By incorporating these findings we conducted a comparison of different signal peptide sequences and identified the most productive as secrecon, a computationally-designed sequence. Importantly, in the context of the secrecon signal peptide and SEAP, we also demonstrated a clear preference for specific amino acid residues at the +1 position (e.g. alanine), and a detrimental effect of others (cysteine, proline, tyrosine and glutamine). When proteins that naturally contain these "undesirable" residues at the +1 position were expressed with their native signal peptide, the heterologous secrecon signal peptide, or secrecon with an additional alanine at the +1 or +1 and +2 position, the level of expression differed significantly and in an unpredictable manner. For each protein, however, at least one of the panel of signal peptide/adjacent amino acid combinations enabled successful recombinant expression. In this study, we highlight the important interplay between a signal peptide and its adjacent amino acids in enabling protein expression, and we describe a strategy that could enable recombinant proteins that have so far proved refractory to expression in HEK293 cells, to be produced in sufficient quantities to answer important biological questions.https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0155340&type=printable
spellingShingle Gülin Güler-Gane
Sara Kidd
Sudharsan Sridharan
Tristan J Vaughan
Trevor C I Wilkinson
Natalie J Tigue
Overcoming the Refractory Expression of Secreted Recombinant Proteins in Mammalian Cells through Modification of the Signal Peptide and Adjacent Amino Acids.
PLoS ONE
title Overcoming the Refractory Expression of Secreted Recombinant Proteins in Mammalian Cells through Modification of the Signal Peptide and Adjacent Amino Acids.
title_full Overcoming the Refractory Expression of Secreted Recombinant Proteins in Mammalian Cells through Modification of the Signal Peptide and Adjacent Amino Acids.
title_fullStr Overcoming the Refractory Expression of Secreted Recombinant Proteins in Mammalian Cells through Modification of the Signal Peptide and Adjacent Amino Acids.
title_full_unstemmed Overcoming the Refractory Expression of Secreted Recombinant Proteins in Mammalian Cells through Modification of the Signal Peptide and Adjacent Amino Acids.
title_short Overcoming the Refractory Expression of Secreted Recombinant Proteins in Mammalian Cells through Modification of the Signal Peptide and Adjacent Amino Acids.
title_sort overcoming the refractory expression of secreted recombinant proteins in mammalian cells through modification of the signal peptide and adjacent amino acids
url https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0155340&type=printable
work_keys_str_mv AT gulingulergane overcomingtherefractoryexpressionofsecretedrecombinantproteinsinmammaliancellsthroughmodificationofthesignalpeptideandadjacentaminoacids
AT sarakidd overcomingtherefractoryexpressionofsecretedrecombinantproteinsinmammaliancellsthroughmodificationofthesignalpeptideandadjacentaminoacids
AT sudharsansridharan overcomingtherefractoryexpressionofsecretedrecombinantproteinsinmammaliancellsthroughmodificationofthesignalpeptideandadjacentaminoacids
AT tristanjvaughan overcomingtherefractoryexpressionofsecretedrecombinantproteinsinmammaliancellsthroughmodificationofthesignalpeptideandadjacentaminoacids
AT trevorciwilkinson overcomingtherefractoryexpressionofsecretedrecombinantproteinsinmammaliancellsthroughmodificationofthesignalpeptideandadjacentaminoacids
AT nataliejtigue overcomingtherefractoryexpressionofsecretedrecombinantproteinsinmammaliancellsthroughmodificationofthesignalpeptideandadjacentaminoacids