EXPRESSION AND CELL-MEMBRANE LOCALIZATION OF CATENINS DURING MOUSE PREIMPLANTATION DEVELOPMENT

We have studied transcription, expression, and membrane localization o f components of the E-cadherin-catenin complex stage by stage during m ouse preimplantation development. Maternal E-cadherin and alpha- and b eta-catenin are stored as mRNA and/or protein in unfertilized eggs and are already assembled into a protein complex at this stage. After fer tilization, it is likely that they mediate adhesion of early-stage bla stomeres, Biosynthesis of plakoglobin is delayed relative to the other components. The temporal mRNA and protein expression patterns of the components of the cadherin-catenin complex correlate with the presence or absence of potential cytoplasmic polyadenylation elements (CPEs) i n the 3'-UTRs of the respective cDNAs, Our results suggest that the co mponents of the E-cadherin-catenin complex derived from both maternal and zygotic gene activity are increasingly accumulated and stored in a nonfunctional form during early cleavage stages and are ready to be u sed for compaction and the formation of the trophectodermal cell layer . (C) 1996 Wiley-Liss, Inc.