Fig. 4. tph-1 regulatory elements. The expression of various GFP fusion to tph-1 in transgenic animals. (A) The genomic structure of the tph-1 gene. tph-1 exons are indicated by filled boxes and untranslated regions are indicated as lines. (B) The strength of GFP expression of various constructs. The construct tph-1-ABCDE::gfp was integrated onto the chromosome; different lines have the construct integrated onto different chromosomes. The other constructs were transmitted as extrachromosomal arrays. The number of transgenic lines carrying each construct has been examined: tph-1::ABCDE::gfp, two lines; tph-1-BCDE, four lines; tph-1-CDE::gfp, three lines; tph-1-DE::gfp, four lines; tph-1-E::gfp, three lines; tph-1-BCE::gfp, three lines. Because GFP levels in AIM and RIH are too weak to survey reliably, only GFP expression in ADF, NSM and HSN was scored. GFP expression of tph-1-ABCDE::gfp, tph-1-BCDE::gfp and tph-1-CDE::gfp in HSN was observed only in adults, tph-1-DE::gfp was expressed in HSN starting at the first larval stage.