upstream of 5 u2032 to the protein coding sequence of a structural gene which controls the expression of the coding region by providing the recognition for rna polymerase and or other factors required for transcription to start at the correct site promoter sequences are necessary but not always sufficient to drive the expression of the gene in this method promoters are defined by their ability to result in expression of the reporter gene complex when cloned upstream of the reporter genes furthermore activation of the promoter by a stress is defined as an increase of activity of the reporter gene complex following application of the stress a u201c fragment u201d constitutes a fraction of the dna sequence of the particular region u201c gene fusion u201d is a hybrid dna fragment comprising a regulatory signal essential for transcription referred to as a promoter fused to at least one structural gene sequence coding for a specific polypeptide the term u201c genomic segment u201d refers to a dna fragment containing a gene regulatory region genomic segments of the present invention are typically derived from the e coli genome and contain regulatory regions responsive to a variety of cellular insults including those produced by contact with crop protection chemicals and herbicides the term u201c regulatory region u201d refers to a dna fragment containing any of the genetic elements responsible for directing gene transcription and translation including promoter or initiation control regions coding regions open reading frames orf and transcriptional termination regions regulatory regions may be positively activated by a variety of stimuli resulting in.