Using ChIP-seq to define TEAD4 target genes genome-wide to decipher how their transcription is maintained in the trophectoderm in a preimplantation mouse embryo model, a team led by researchers at the University of Kansas Medical Center found that a "lack of nuclear localization of TEAD4 impairs the TE [trophectoderm]-specific transcriptional program in inner blastomeres, thereby allowing their maturation toward the ICM [inner cell mass] lineage." In a paper published online in advance in PNAS this week, the Kansas-led team also reports having found that "restoration of TEAD4 nuclear localization maintains the TE-specific transcriptional program in the inner blastomeres and prevents segregation of the TE and ICM lineages and blastocyst formation."
University of Oxford's Robert Belshaw and his colleagues say that endogenous retroviruses that lack the env gene are "genomic superspreaders that take over a significant proportion of their host's genome." Analyzing ERV loci recovered from 38 mammal genomes in an in silico screening, Belshaw et al. found that "when ERVs lose the env gene, their proliferation within that genome is boosted by a factor of [about] 30," they write in PNAS.
Elsewhere in this week's Early Edition, a public-private team made up of researchers at the Karlsruhe Institute of Technology and at SunGene in Gatersleben, Germany, describes a >gene-targeting system "that is suitable for all transformable plants regardless of transformation efficiency."