Home | Resources | FAQs
What is the rationale for offering viral particles for ORFs w/o stop codon?
It sounds confusing but really all of our LentiORFs have a STOP codon. The difference is –where. What we refer to as “no stop” means that the natural stop codon of the ORF has been removed and instead of terminating at the last amino acid of that ORF the translation of the protein goes on through the attB2 site and terminates immediately after that in the vector. This is done so that whoever buys such ORF as a glycerol stock of a LentiORF clone had a way of creating C-terminal fusions of his ORF of interest. The stop codon in the vector is flanked by unique sites so the customer can cut it out and replace with the tag of his choice. The trade off for such flexibility is ~13-15 extra amino acids at the C-ter of the protein.
If a customer buys ready to use virus he cannot modify it to make a fusion. We have more of the “no stop” LentiORFs than “with natural STOP” and so for some LentiORFs we only have one kind. Whether the LentiORF expression clone is “stop “or “no stop” is defined by the source ORF Entry clone from ORFeome collaboration and these are coming to us more and more in only the “no stop” flavor.