Single-cell RNA-seq of blastomeres from 2- to 32-cell stage mouse embryos

Transcriptomes were determined for all blastomeres of 28 embryos at the 2- (n=8), 4- (n=16) and 8-cell (n=4) stages, and for individual cells taken from 16- (n=6) and 32- (n=6) cell stage embryos. We also carefully monitored the 2- to 4-cell divisions noting whether the cleavage plane was meridional (M, along the Animal-Vegetal (AV) axis marked by the second attached polar body) or equatorial (E, bisecting the AV axis) and the order in which such divisions occurred. This resulted in four groups of 4-cell stage embryos: ME, EM, MM and EE, which were all collected 10 hours after the first 2- to 4-cell division.