Abstract
The targeting of positional information to specific regions of the oocyte or early embryo is one of the key processes in establishing anterior-posterior and dorsal-ventral polarity. In many developmental systems, this is accomplished by localization of mRNAs. The germ line-specific Drosophila orb gene plays a critical role in defining both axes of the developing oocyte, and its mRNA is localized in a complex pattern during oogenesis. We have identified a 280-bp sequence from the orb 3' untranslated region capable of reproducing this complex localization pattern. Furthermore, we have found that multiple cis-acting elements appear to be required for proper targeting of orb mRNA.
