Cellular diversification during development often requires the asymmetric distribution of mRNAs and proteins that determine cell fates.  In the fly Drosophila melanogaster, these asymmetries are established during oogenesis by reciprocal signaling between the germ line-derived oocyte and the surrounding somatic follicle cells.  Here I present evidence that the function of two proteins, Mago Nashi and Tsunagi/Y14, are required within the oocyte for the asymmetric distribution of determinants in response to signaling between the follicle cells and oocyte.  These signaling events establish the major body axes of the embryo and adult, and are required for the differentiation of primordial germ cells (cells that form eggs and sperm).

Robert E. Boswell, Ph.D. Professor, Director, University of Colorado, National Institutes of Health, Minority Biomedical Research Support, Initiative for Minority Student Development Program.