Detecting DNA sequences that inhibit transcription repressors, to provide sequences for stable gene expression in transgenic organisms, comprises transfecting a host cell with candidate sequences and repressor and reporter genes

摘要

Detecting, and optionally selecting, a DNA sequence that enhances stable expression of a gene, comprising inserting the sequence into a vector between a DNA sequence involved in the induction of transcription of gene-repressing chromatin and a reporter gene, and detecting expression of the reporter gene in a host cell, is new. Detecting, and optionally selecting, a DNA sequence which possesses a stable expression-enhancing quality, is new and comprises: (a) cloning DNA fragments less than 5000 base pairs into a vector between a DNA sequence (I) involved in the induction of transcription of gene-repressing chromatin and a reporter gene comprising a promoter (II), so that the distance between (I) and (II) is less than 5000 base pairs; (b) introducing the vectors to host cells where the promoter may be active but induction of gene-repressing chromatin results in repression of the transcription of the reporter gene; and (c) selecting host cells to identify a host cell exhibiting reporter gene activity. Independent claims are also included for the following: (1) a repression-inhibiting DNA sequence that can be detected, selected and optionally cloned using the above method, and is isolated from a plant or vertebrate, is a synthetic sequence, or is constructed using genetic engineering; and (2) making a DNA construct comprising a gene that is to be stably expressed, wherein a stable expression-promoting DNA sequence is integrated in accordance with (1) in fewer than 2000 base pairs of the gene.