Worm Breeder's Gazette 9(2): 84
These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.
We are interested in the physical limits of the eT1 translocation. Previous work (Rosenbluth and Baillie 1981) showed that eT1(III,V) was the product of two breaks; one on LGIII (between sma-3 and sma-2) and one on LGV (between dpy-11 and unc-42). While it was shown that eT1(V) carried the whole of the right arm of LGIII, it was only assumed that eT1(III) carried the whole left arm of LGV. The possibility remained that eT1 was the product of more than two breaks and only the medial portion was translocated. The following two tests show the translocated portion of LGV (segregating from LGIII on eT1(III)) extends to at least unc-60. This demonstration was made possible as a result of having an unc-60 allele, s1310, induced on the eT1 chromosome. The outcross progeny from the cross +;unc-60(m35)/ unc-60(s1310) eT1 X +;unc-60(m35) dpy-11(e224)/eT1 will be Unc-60's, ozygotes) and Wild types. The ratio of F1 wildtypes giving DpyUnc to those giving just Unc worms depends on which chromosome s1310 segregates with. If a 1:1 ratio is observed, s1310 is on eT1(III), if a 1:0 ratio for Unc's is observed, than s1310 is on eT1(V). In fact the data indicated eT1(III) was the answer (8 DpyUnc to 4 Unc).In confirmation, +/eT1 unc-60(s1310);unc-60(e890) crossed to +/eT1 gave Unc-60 male progeny in the F1; again indicating eT1(III) is the position of s1310 since the two unc-60 alleles segregated into the same oocyte. Genetic evidence now shows the translocated portion of LGV on eT1( III) covers the the region between unc-60 and a point between dpy-11 and unc-42.Supported by NSERC and MDA of Canada grants to D.L.B.