Fig. 1.

Structure of the desat1 gene and transgenes. (A) The desat1 gene includes five alternative first exons (shown as shaded boxes and indicated RA, RC, RE, RB and RD), all of which combine with exons 2–5 (corresponding to the coding region) to produce five transcripts all translated into the Desat1 desaturase. (B) Transgenes with the desat1 regulatory regions were built with: (i) the sequence of each region combined with its exon [PRR(RA) to PRR(RD)], and (ii) with the putative regulatory region either complete PRR(-6908) or deleted of the most distal regions down to the minimal regulatory region PRR(-660). These PRR sequences were fused to a reporter sequence corresponding either to the GFP sequence to visualize desat1 expression or to the Gal4 sequence to target UAS transgenes.