Isolation and characterization of Df(3R)BSC861
Kim Cook, Stacey Christensen and Kevin Cook
Bloomington Stock Center
Indiana University
Df(3R)BSC861 was isolated as a FLP recombinase-induced recombination event involving P{XP}d06626 and PBac{WH}CG42557f00294. The deletion was isolated as a chromosome carrying two copies of the miniwhite marker in progeny of w1118; P{hs-hid}3, Dr1/TM6C, Sb1 cu1 females crossed to P{hsFLP}1, y1 w1118; P{XP}d06626/PBac{WH}CG42557f00294 males. The males were heat shocked as larvae as described in Parks et al., Nature Genetics 36: 288-292, 2004 (FBrf0175003). This cross and crosses in preceding and succeeding generations maintained the original genetic background of the Exelixis insertion stocks (Thibault et al., Nature Genetics 36: 283-287, 2004; FBrf0175002). The recombination event generated the genetic element P+PBac{XP3.WH3}BSC861 from the segment of P{XP}d06626 to the left of its FRT site and the segment of PBac{WH}CG42557f00294 to the right of its FRT site. The Gene Disruption Project determined the insertion site of P{XP}d06626 to be Release 3 genomic coordinate 25692192 on arm 3R, which corresponds to Release 5 coordinate  3R:25702826 . The predicted cytology of both coordinates is 99C5. The insertion site of PBac{WH}CG42557f00294 is Release 5 genomic coordinate 25760302 on arm 3R with a predicted cytology of 99C7. Consequently, the breakpoints of Df(3R)BSC861 predicted from the Release 5 genomic coordinates of the transposable element insertion sites are  3R:25702826 ;25760302 and the cytological breakpoints predicted from these coordinates are 99C5;99C7. To confirm the presence of the deficiency, we showed that a 895 base pair fragment spanning the P{EPgy2}EY22844 insertion site could not be amplified from Df(3R)BSC861/P{EPgy2}EY22844 flies using primers 5'-GCCAGTTGGTTTGTCATGTTTGCC-3' and 5'-GAGCGTTCTGGTCACTTTCGGG-3'.