Patent ID: 7767455

Claim:
A method for detecting RNA export from the cell nucleus of a eukaryotic target cell, comprising (a) providing a polynucleotide which codes for a reporter protein and which further comprises (i) a cis-active RNA export signal which is in operative linkage with the polynucleotide (ii) a functional 5′ splice donor without a 3′ splice acceptor, (iii) an A/T content that is greater than 50%, which reduces the metabolic stability of a reporter RNA which encodes said reporter protein in the cell nucleus; (b) introducing the polynucleotide into the cell nucleus of the target cell so that it is present therein in operative linkage with a transcription control sequence, and that upon transcription of the polynucleotide there is generation of a transcript in which the segment of the transcript coding for the reporter protein cannot be subjected to any efficient splicing process; (c) providing a trans-active export factor; (d) transcribing the polynucleotide; and (e) determining whether the resulting transcript is exported from the cell nucleus.