Differential induction of antibacterial transcripts in Drosophila susceptible and resistant to parasitism by Leptopilina boulardi.
Two well-described elements of the immune response of insects include encapsulation of metazoan parasites (blood-cell-mediated) and the production of antibacterial peptides (humoral and/or cellular). However, the possible functional interrelationship between cellular encapsulation and antibacterial responses, and the extent to which the two components may be co-regulated, are poorly understood. We used a novel approach involving strains of Drosophila resistant (R) or susceptible (S) to the wasp parasitoid Leptopilina boulardi to study the expression of three genes involved in the antibacterial response: Dorsal-related immunity factor (Dif), Cecropin (CecA1) and Diptericin (Dip). Both S and R strains produced high levels of all antibacterial transcripts upon bacterial injection. However, when parasitized the R strain showed no induction whilst the S strain did. This lack of antibacterial transcript induction in the parasitized R strain not only clarifies the separation of these two types of immune response but also raises the fascinating possibility of a link in their genetic regulation.
Coustau
C
C
Department of Entomology, University of Wisconsin-Madison, Russell Laboratories, USA.
Carkion
Y
Y
Nappi
A
A
Shotkoski
F
F
ffrench-Constant
R
R
D000818:Animals; D000900:Anti-Bacterial Agents; D004268:DNA-Binding Proteins / Q000235:genetics*; D004330:Drosophila / Q000276:immunology* / Q000469:parasitology; D029721:Drosophila Proteins; D004926:Escherichia coli / Q000276:immunology; D007301:Insect Hormones / Q000235:genetics*; D019476:Insect Proteins; D014157:Transcription Factors; D014863:Wasps
D000900:Anti-Bacterial Agents; D004268:DNA-Binding Proteins; C084428:Dif protein, Drosophila; C054756:DptA protein, Drosophila; D029721:Drosophila Proteins; D007301:Insect Hormones; D019476:Insect Proteins; D014157:Transcription Factors