Epithelia are tissues with a pronounced apicobasal polarity that are common to most multicellular organisms. They serve as boundaries between tissue compartments and control the directional exchange of molecules. Morphogenetic changes in epithelia contribute to the elaboration of the final body plan. Hence, the establishment and maintenance of epithelial polarity, and integrity, is of crucial importance for the development of multicellular organisms. A combined genetic, cell biological and molecular dissection of these processes in Drosophila has revealed that some of the underlying mechanisms and molecules are conserved between vertebrates ann Drosophila, but has also uncovered novel gene products that will shed light on tbe mechanisms involved in controlling epithelial organization.
