The invention relates to a vector comprising: a 5 nucleic acid that is homologous to a genomic sequence 5 of a stop codon of a constitutively expressed gene; an exogenous nucleic acid; a 3 nucleic acid that is homologous to a genomic sequence 3 of the stop codon of the constitutively expressed gene; a translation interruption-reinitiation signal operably linked to the 5 nucleic acid and the exogenous nucleic acid, wherein the translation interruption-reinitiation signal is capable of replacing the stop codon of the constitutively expressed gene.

Provided herein are compositions and systems comprising an engineered release factor and methods for producing the same. Also provided herein are compositions, systems, and methods for producing a polypeptide comprising a non-canonical amino acid.

The invention relates to a vector comprising: a 5 nucleic acid that is homologous to a genomic sequence 5 of a stop codon of a constitutively expressed gene; an exogenous nucleic acid; a 3 nucleic acid that is homologous to a genomic sequence 3 of the stop codon of the constitutively expressed gene; a translation interruption-reinitiation signal operably linked to the 5 nucleic acid and the exogenous Targeting nucleic acid, wherein the translation interruption-reinitiation signal is capable of replacing the stop codon of the constitutively expressed gene.

Compositions and methods to attenuate the immunosuppressive activity of TGF- through the use of bi-functional shRNAs is described herein. The bi-functional shRNAs of the present invention knocks down the expression of furin in cancer cells to augment tumor antigen expression, presentation, and processing through expression of the GM-CSF transgene.