Schulze, S., Sinclair, D.A., Silva, E., Fitzpatrick, K.A., Singh, M., Lloyd, V.K., Morin, K.A., Kim, J., Holm, D.G., Kennison, J.A., Honda, B.M. (2001). Essential genes in proximal 3L heterochromatin of Drosophila melanogaster.  Mol. Gen. Genet. 264(6): 782--789.

FBrf0134775

Research paper

We have further characterized essential loci within the centric heterochromatin of the left arm of chromosome 3 (3L) of Drosophila melanogaster, using EMS, radiation and P element mutagenesis. We failed to find any new essential genes, a result that suggests a lower-than-average gene density in this region. Mutations affecting expression of the most proximal gene [lethal 1, l1 or l(3)80Fj] act as dominant suppressors of Polycomb (Pc), behavior which is consistent with a putative trithorax group (trx-G) gene. The third gene to the left of the centromere [lethal 3, l3 or l(3)80Fh] is likely to correspond to verthandi (vtd), a known trx-G gene that plays a role in the regulation of hedgehog (hh) expression and signalling. The intervening gene [lethal 2, l2 or l(3)80Fi] is required throughout development, and mutant alleles have interesting phenotypes; in various allelic combinations that survive, we observe fertility, bristle, wing, eye and cuticle defects.