Worm Breeder's Gazette 9(2): 91
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.
mnDp10 is a large duplication of the right side of X, covering the myo-2 gene. Northern assays indicate that an XX hermaphrodite carrying two copies of mnDp10 accumulates twice as much myo-2 mRNA as a wild-type hermaphrodite. This observation indicates that expression of the myo-2 gene is in proportion to its copy number, an important control for our dosage compensation experiments. In examining three other X-linked loci not covered by this duplication, we discovered that the two dosage compensated loci, uxt-1 (adjacent to sup-7) and uvt-4 (adjacent to the vit genes) are also affected by this duplication. The levels of uxt-1 and uvt-4 mRNA are twice as high in the duplication strain as in a wildtype hermaphrodite strain. However, act-4 expression remains unchanged by mnDp10. (Expression of uxt-1 and uvt-4 is elevated in dpy-21, dpy27, dpy-28, and egl-16 strains whereas expression of act-4 is not). We are currently investigating the relevance of these observations to the mechanism of dosage compensation. (Phil Meneely has observed a similar phenomenon: lin-15 hypomorphs are suppressed by X duplications not covering this locus.)