Salivary gland development in Drosophila melanogaster

The Drosophila salivary gland is proving to be an excellent experimental sy stem for understanding how cells commit to specific developmental programs and, once committed, how cells implement such decisions. Through genetic st udies, the factors that determine where salivary glands will form, the numb er of cells committed to a salivary gland fate, and the distinction between the two major cell types (secretory cells and duct cells) have been discov ered. Within the next few years, we will learn the molecular details of the interactions among the salivary gland regulators and salivary gland target genes. We will also learn how the early-expressed salivary gland genes coo rdinate their activities to mediate the morphogenetic movements required to form the salivary gland and the changes in cell physiology required for hi gh secretory activity. (C) 2000 Elsevier Science Ireland Ltd. All rights re served.