UASt regulatory sequences drive expression of a 500bp cDNA fragment from the 5' end of the grass coding sequence, inserted as an inverted repeat (IR) in a modified pUAST vector, pUAST-R57, which includes a 282bp genomic fragment of Ret, containing introns 5 and 6 between the two IR fragments, to enhance the effect of RNAi.
Flies expressing grassdsRNA.IR.Scer\UAS under the control of Scer\GAL4Act5C.PI show comparable levels of mortality to wild type in response to mild wounding in 7-8 day old adults.
Expression of grassdsRNA.IR.Scer\UAS, under the control of Scer\GAL4da.G32 does not affect activation of melanization during pupariation, nor does it suppress lethality induced by the inactivation of Spn27A.
Flies expressing grassdsRNA.IR.Scer\UAS under the control of Scer\GAL4da.G32 exhibit an immune-deficiency phenotype similar to Tl pathway mutants: these flies are highly susceptible to Enterococcus faecalis (gram-positive) and fail to properly induce Drs after infection with Micrococcus luteus (gram-positive).
Silencing of grass, through expression of grassdsRNA.IR.Scer\UAS, under the control of Scer\GAL4da.G32, does not impair Tl activation by fungus or yeast.