Patent ID: 7026123

Claim:
A method of identifying a nucleotide sequence that modulates the activity of a transcriptional regulatory region, comprising: a) incorporating into a host cell population a generated library of plasmids wherein the generated library is a collection of plasmids, wherein the library of plasmids comprises multiple non-redundant U-tags, each plasmid having one or more non-redundant U-tags, each U-tag conferring an identifying marker on each plasmid in the library, and each plasmid in the generated library comprises a first DNA construct and a second DNA construct, wherein; i) the first DNA construct comprises a transcriptional regulatory region, a reporter sequence, and an mRNA stabilizing sequence; and, ii) the first DNA construct further comprises one or more U-tags inserted into one or more locations selected from the group of locations consisting of a 3′ UTR of the transcriptional regulatory region, a 5′ UTR of the transcriptional regulatory region, a coding region of the reporter sequence, and one or more intron sequences occurring within the first DNA construct; and, iii) the second DNA construct comprises a promoter active in a host cell of the host cell population, wherein the promoter is operably linked to a nucleotide sequence of interest; and b) screening for an alteration in the expression levels of each U-tag; and, c) identifying the nucleotide sequence of interest based on U-tag identity.