Genomic fragment that encompasses the cyst gene and includes its promoter (derived from the BACR27M12 BACPAC clone). Sequence encoding the DH and PH domains has been deleted. Silent mutations have been introduced at two distinct sites to confer resistance to RNAi mediated by the P{TRiP.HMS01750} transgene. A S(GGGGS)[[2]] linker followed by a sfGFP tag has been inserted at the C-terminal end of the cyst coding sequence.