Although glp-1 mRNA is abundantly expressed in all blastomeres of C. elegans embryos up to the eight-cell stage, its protein is present in only the anterior AB blastomeres of two- and four-cell embryos. Thus, its translation, which is required for gonad and embryonic development, is spatially and temporally controlled. This occurs via the spatial control (SCR)and the temporal control (TCR) regions of the 3′ UTR of glp-1. Now Ogura et al. report, on p. 2495, that POS-1, which translationally regulates another maternal transcript, apx-1, represses glp-1 translation by binding to its SCR. A yeast two-hybrid screen also identified a POS-1-interacting protein, SPN-4 (an RNP-type, RNA-binding protein), that binds to the TCR of glp-1 and is required for its translation in anterior blastomeres. The authors propose that a balance between these two proteins controls glp-1 translation. Given the pleiotropic phenotypes of pos-1and spn-4 mutants, these proteins probably also regulate the translation of other maternal RNAs.