UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

The homeotic and segmentation genes interact differently with the polycomb-group genes in Drosophila melanogaster McKeon, Joanie


Members of the Polycomb (Pc)-group of genes have similar phenotypes, including posterior transformation of embryonic and adult segments, sensitivity to changes in dosage of the bithorax and Antennapedia complexes, and enhancement of Polycomb phenotypes in transheterozygotes. However, genetic and molecular evidence suggests that not all members of the Pc-group have equivalent functions. I examined the protein distribution of the three homeotic genes Ultrabithorax, Antennapedia, and Sex combs reduced, and the segmentation gene engrailed to directly assay Pc-group function. The timing, severity, tissue-specificity, and pattern of gene expression differed in each mutant. These results support the hypothesis that different members of the Pc-group have different functions. My results indicate that it is likely that there is at least one pathway in which Polycomb and extra sex combs are at the head, and that some Pc-group genes function in subpathways. I have also shown that some members of the Pc-group function in regulating the segmentation as well as the homeotic genes and therefore have a more general role in development.

Item Media

Item Citations and Data


For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.