Drosophila long-chain acyl-CoA synthetase acts like a gap gene in embryonic segmentation

Long-chain acyl-CoA synthetases (ACSLs) convert the long chain fatty acids to acyl-CoA esters, the activated forms participating in diverse metabolic and signaling pathways. dAcsl is the Drosophila homolog of human ACSL4 and their functions are highly conserved in the processes ranging from lipid metabolism to the establishment of visual wiring. In this study, we demonstrate that both maternal and zygotic dAcsl are required for embryonic segmentation. The abdominal segmentation defects of dAcsl mutants resemble those of gap gene knirps (kni). The central expression domain of Kni transcripts or proteins was reduced whereas the adjacent domains of another gap gene Hunchback (Hb) were correspondingly expanded in these mutants. Consequently, the striped pattern of the pair-rule gene Even-skipped (Eve) was disrupted. We propose that dAcsl plays a role in embryonic segmentation at least by shifting the anteroposterior boundaries of two gap genes.