Mouse oocyte and one-cell embryo polysomal mRNA

Transcriptional activation in mammalian embryos occurs in a stepwise manner. In mice, it begins at the late one-cell stage, followed by a minor wave of activation at the early two-cell stage, and then the major genome activation (MGA) at the late two-cell stage. Cellular homeostasis, metabolism, cell cycle, and developmental events are orchestrated before MGA by time-dependent changes in the array of maternal transcripts being translated (i.e., the translatome). Despite the importance of maternal mRNA and its correct recruitment for development, neither the array of recruited mRNA nor the regulatory mechanisms operating have been well cheracterized. We present the first comprehensive analysis of changes in the maternal component of the zygotic translatome during the transition from oocyte to late one-cell stage embryo, revealing global transitions in the functional classes of translated maternal mRNAs, and apparent changes in the underlying cis-regulatory mechanisms.

8

Potireddy S, Vassena R, Patel BG, Latham KE