Disease relevance of Dpt

• Inhibition of nitric oxide synthase (NOS) increased larval sensitivity to gram-negative bacterial infection, and abrogated induction of the antimicrobial peptide Diptericin [1].
• Interestingly, caspar mutant flies showed increased antibacterial immune responses including increased resistance to bacterial infection and a constitutive expression of diptericin, a representative antibacterial peptide gene [2].
• More precisely, our data points to an important role for the antimicrobial peptide Diptericin against orally infectious Gram-negative bacteria, emphasizing the critical role of local antimicrobial peptide expression against food-borne pathogens [3].

High impact information on Dpt

• NO induction of Diptericin reporters in the fat body required immune deficiency (imd) and domino [1].
• To dissect the regulation of this gene, we have transformed flies with a fusion gene in which the reporter beta-galactosidase gene is under the control of 2.2 kb upstream sequences of the diptericin gene [4].
• Conversely, ectopic expression of caspar strongly suppressed the infection-dependent gene expression of diptericin, which allowed bacterial outgrowth [2].
• The DLAK(K50A) mutant also inhibits nuclear kappaB binding activity and kappaB-dependent diptericin reporter gene activity in a dose-dependent manner, but the kappaB-dependent diptericin reporter gene activity can be rescued by overexpression of wild type DLAK [5].
• Furthermore, we found that ectopic expression of Nef inhibits Drosophila innate immune responses including Relish NF-kappaB activation with subsequent induction of an antimicrobial peptide, diptericin [6].

Biological context of Dpt

• We show that such a fusion gene is inducible by injection of live bacteria or complete Freund's adjuvant and respects the tissue specific expression pattern of the resident diptericin gene [4].
• The upstream sequences of the diptericin and cecropin Al genes, which have been investigated in detail, contain two, respectively one sequence element homologous to the binding site of the mammalian nuclear factor kappaB [7].
• Specific assays for Dip A and Dip B were used to show that for each of these isozymes, the activity in an adult is proportional to gene dosage [8].

Other interactions of Dpt

• Estimates of variation levels show that the genes are not exceptionally polymorphic, but Andropin and Diptericin have patterns of variation that differ significantly from neutrality [9].

References