In many organisms, the transition from oocyte to embryo occurs in the absence of mRNA transcription. Therefore, early developmental programs rely on maternal mRNAs and proteins that are synthesized during oogenesis. The regulated translation of maternal RNAs is essential for the proper deployment of regulatory factors during early embryogenesis. Recent studies suggest that the degradation of ma...

Localization of maternal mRNAs in many developing organisms provides the basis for both initial polarity during oogenesis and patterning during embryogenesis. Prominent examples of this phenomenon are found in Xenopus laevis, where localized maternal mRNAs generate developmental polarity along the animal/vegetal axis. Targeting of mRNA molecules to specific subcellular regions is a fundamental ...

Background: The role of the placenta in regulating micronutrient transport in response to maternal status is poorly understood.Objective: We investigated the effect of prenatal nutritional supplementation on the regulation of placental iron and zinc transport.Methods: In a randomized trial in rural Gambia [ENID (Early Nutrition and Immune Development)], pregnant women were allocated to 1 of 4 n...

A current hypothesis of ovine parturition proposes that fetal adrenal cortisol induces placental E2 production, which, in turn, triggers intrauterine PG production. However, recent evidence suggests that cortisol may directly increase PG production in trophoblast-derived tissues. To separate cortisol-dependent and estrogen-dependent PG production in sheep intrauterine tissues, we infused single...

[2004]; also see zebrafish data discussed below). eggs, where maternal Wnt protein can mask effects on the embryo. Injection of synthetic Wnt11 RNA into oo-cytes causes dorsalization associated with increased expression of Wnt target genes such as siamois and Xnr3. By contrast, depletion of maternal Wnt11 mRNA in oocytes leads to reduction of dorsoanterior embry-onic structures in a manner simi...