Figure 1

The BhC4-1 core promoter and diagrams of the analyzed constructs. The sequence of the 97 bp (-57/+40) BhC4-1 core promoter region [GenBank:U13892] is shown in (A). The TATA motif and the initiator element (Inr) are underlined and in italic, respectively. The experimentally defined transcription start site (+1) is the first T (underlined, italic) in the Inr element [13]. The sequences similar to Motif 8 and Motif 10 (MTE) [7, 29] are shown in bold and bold/italic, respectively. (B) The upper diagram shows the core promoter elements identified in the BhC4-1 core promoter. The numbers below the diagram correspond to the position of each element, defined in relation to the experimentally mapped transcription start site (+1) [13]. The lower diagram, drawn for comparison, consists of a hypothetical insect core promoter containing a TATA motif, and Inr and an MTE. The numbers below the diagram are defined in relation to the transcription start site (+1), and indicate the position in which these elements are more commonly found in insect core promoters. The core promoter elements drawn in the lower diagram consist of the subset of core promoter elements that have been identified. A particular core promoter might contain some, all or none of these elements [2, 4]. The motif 8 element (Motif 8 E) is not shown in the bottom diagram because its preferential location in insect core promoters has not been defined. (C) Diagrams of the transgenes analyzed in this work. The arrow above the BhC4-1 core promoter diagram indicates the transcription start site and the direction of transcription.