The mechanisms used to establish embryonic polarity are still largely unknown. A recent paper((1)) describes the expression pattern of the gene
glp-1, which is required for induction events during development of the nematode Caenorhabditis elegans. Although
glg-1 RNA is found throughout the early embryo, Glp-1 protein is only expressed in anterior cells. This negative translational regulation in posterior cells is shown to be mediated through sequences in the
glp-1 3'untranslated region (3'UTR). Thus in nematodes, as in Drosophila, translational repression is one mechanism used to establish the embryonic anterior-posterior axis.