Searle Scholars Program

The development of multicellular animals requires that all cells have two types of information: where they are relative to their neighbors (positional information) and what structure they should generate (identity information). We are interested in how positional and identity information are integrated during animal development and use the fruit fly, Drosophila melanogaster, as a model system. In recent years, our work has focused on the homeotic selector (HOX) genes which link these two types of information: their large cis regulatory regions interpret positional information and their protein products control cellular identities by regulating the transcription of downstream target genes. The HOX genes have been structurally and functionally conserved throughout evolution and probably perform analogous functions throughout the animal kingdom. We are interested in the following aspects by which HOX proteins control cellular identities: (1) how the HOX proteins select the correct target genes in vivo, (2) post-translational mechanisms controlling HOX function, and (3) the identification of HOX target genes that contribute to segmental differences in the fly.