Ion channels are proteins expressed in the plasma membrane of electrogenic cells. In the zygote and blastomeres of the developing embryo, electrical modifications result from ion currents that flow through these channels. This phenomenon implies that ion current activity exerts a specific developmental function, and plays a crucial role in signal transduction and the control of embryogenesis, f...

Preimplantation embryo development involves four stages: fertilization, cell cleavage, morula and blastocyst formation. During these stages, maternal and zygotic epigenetic factors play crucial roles. The gene expression profile is changed dramatically, chromatin is modified and core histone elements undergo significant changes. Each preimplantation embryo stage has its own characteristic epige...

Production of sires with high breeding potential is indispensable for prompt and reliable breeding using their semen in the cattle industry. Currently, in Japan, we aim to further the production of Japanese black sires via a new breeding system that uses genetically homologous monozygotic twins so that better growth performance and carcass traits can be translated to the increased production of...

STUDY QUESTION Is the amount of cell-free DNA released by human embryos into culture medium correlated with embryo morphological features? SUMMARY ANSWER The mitochondrial DNA (mtDNA) content of culture medium is significantly associated with the fragmentation rate on Days 2 and 3 of embryo development, whether the oocyte came from women ≤ 35 or >35 years old. WHAT IS KNOWN ALREADY Cellular...

A large increase in surface area must accompany formation of the amphibian embryo first cleavage furrow. The additional membrane for this areal expansion has been thought to be provided entirely from cytoplasmic stores during furrowing. We have radioiodinated surface proteins of fertilized, precleavage Xenopus laevis embryos and followed their redistribution during first cleavage by autoradiogr...

BACKGROUND Orientation and positioning of the cell division plane are essential for generation of invariant cleavage patterns and for unequal cell divisions during development. Precise control of the division plane is important for appropriate partitioning of localized factors, spatial arrangement of cells for proper intercellular interactions, and size control of daughter cells. Ascidian embry...

Human embryos resulting from abnormal early cleavage can result in aneuploidy and failure to develop normally to the blastocyst stage. The nature of paternal influence on early embryo development has not been directly demonstrated although many studies have suggested effects from spermatozoal chromatin packaging, DNA damage, centriolar and mitotic spindle integrity, and plasma membrane integrit...

During mammalian pre-implantation embryo development, when the first asymmetry emerges and how it develops to direct distinct cell fates remain longstanding questions. Here, by analyzing single-blastomere transcriptome data from mouse and human pre-implantation embryos, we revealed that the initial blastomere-to-blastomere biases emerge as early as the first embryonic cleavage division, followi...

The freshwater angelfish, Pterophyllum scalare like many other cichlids show parental care of embryos and larvae. This study was carried out to investigate the embryonic development P. scalare, which shows biparental substrate brooding. During adult reproductive behavior observed. Once eggs were fertilized upon spawning, early later stages observed, documented various embryo length measurements...