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Chimeric receptor design: What, Why and How
In silico protocol

Chimeric receptor design: What, Why and How


Protocol for making protein chimeras with a rat G protein coupled receptor (RI7) and Your Favorite Receptor. The order of the DNA sequence looks like this: RI7-[Your Favorite Receptor]-RI7


One of the requirements for a working GPCR is that the receptor should be localized into the outside membrane of yeast cell. By replacing the N-terminal part of Your Favorite Receptor by the N-terminal ends of a receptor that is known to be localized into the outside membrane of Saccharomyces cerevisiae (R17), Your Favorite Receptor (YFR) will also be localized into the membrane. The C-terminal part of a GPCR is the alpha subunit binding region. If this is replaced by the RI7 regions a higher affinity with the alpha subunit can be reached [1].


With this step-by-step protocol we guide you trough all the in silico designing steps. After this the DNA can be transformed in yeast and you have your own olfactory yeast!

In silico protocol

  1. 1. What: Get your receptor protein sequence code
    Why: To introduce a new receptor chimera in yeast you should start with a GPCR with at least a known sequence and preferably a known ligand.
    How: By using earlier research on GPCRs. For example a nice GPCR database is Copy the DNA sequence and the protein sequence in a text file.
  2. 2. What: look for the transmembrane regions
    Why: Normally GPCRs have seven transmembrane regions. The N-terminal loop is important for the localization in the membrane and should be replaced by the RI7 N-terminal sequence. The C-terminal region directly after the last transmembrane part codes for the alpha-subunit binding region. If this region is replaced by the RI7 region a higher affinity with the alpha subunit can be reached.
    How: Go to, enter the protein sequence code and find protein motifs for Saccharomyces cerevisiae and the original species. Compare the Global domain table. Ideally it finds seven transmembrane regions that all have approximately the same length (quite a conserved domains are found ). When this is not the case, investigate the hydrophobicity by a hydrophobicity index (analysis can be done by Matlab Bioinformatics tool, but this less conclusive due to multiple hydrophobicity indexes).