SCREENING METHODS FOR IDENTIFICATION OF EFFICIENT PRE-TRANS-SPLICING MOLECULES

摘要

The present invention provides methods and compositions for rapid high capacity functional screening to identify optimal pre-trans-splicing molecules (PTMs). The compositions of the invention include PTM expression libraries capable of encoding candidate PTMs designed to interact with a target precursor messenger RNA molecule (target pre-mRNA) and mediate a trans-splicing reaction resulting in the generation of a novel chimeric RNA molecule (chimeric RNA). The candidate PTMs of the invention encode a portion of a first reporter molecule and may encode one or more other reporter molecules, which can be used to select for cells expressing optimal PTMs (efficient and specific). The compositions of the invention also include cells that express a target pre-mRNA encoding the remaining portion of the first reporter molecule. The screening methods of the invention encompass (i) contacting a PTM expression library with cells expressing a target pre-mRNA under conditions in which a trans-splicing reaction will occur in the presence of an optimal PTM (expressed by the library vector) resulting in the formation of a chimeric repaired RNA molecule capable of encoding at least one reporter molecule; (ii) selecting for cells expressing the repaired reporter molecule wherein expression of the reporter molecule indicates the presence of an optimal PTM in the selected cell; and (iii) identifying the optimal PTM expressed in the selected cell(s). The additional reporter molecule(s) can be used to assess both specific and non-specific trans-splicing, as well direct PTM expression.