Studies are presented on the ability of low-molecular-weight nuclear DNA fractions to hybridize to higher-molecular-weight nuclear DNAs taken from different stages of early developing sea-urchin embryos, Strongylocentrotus purpuratus. Using preparative DNA-DNA hybridization, a fraction of 60-s mid-blastula DNA was isolated for its ability to anneal to 10-s morula DNA. Approximately 80 regions o...

Manipulation with early mammalian embryos is the one of the most important approach to study preimplantation development. Artificial cell fusion is a research tool for various biotechnological experiments. However, the existing methods have various disadvantages, first of them impossibility to fuse selected cells within multicellular structures like mammalian preimplantation embryos. In our exp...

Xenopus embryos were transferred into media containing aphidicolin at late blastula, mid-gastrula, and early neurula stages. In each case, embryos continued to differentiate in the absence of DNA replication. When the inhibitor was added at late blastula, embryos continued to develop for about 8 h. However, when aphidicolin was added at the early neurula stage, development could be seen for up ...

Mammalian fertility absolutely depends on synchronized development of the blastocyst to the stage when it is competent to implant, and the uterus to the stage when it is receptive to implantation. However, the molecular basis for the reciprocal interaction between the embryo and the uterus remains largely unexplored. One potentially important mechanism involves signaling between an evolutionari...

background: the presence of rennin-angiotensin components in mammalian ovaries and their involvement in ovarian physiology have been established. in the present study, effects of angiotensin ii (ang ii) on sodium-potassium adenosine triphosphatase (na+/k+/atpase) expression and development of sheep embryos was evaluated. methods: the abattoir-derived cumulus oocyte complexes (coc) were randomly...

Currently in vitro culture of mouse preimplantation embryos has become a very important technique to investigate different mechanisms of early embryogenesis. However, there is a big difference in the preimplantation development between mammalian species. Despite close relatedness to mice, in vitro cultivation of rat preimplantation embryos is still delicate and needs further investigation and o...

Current human fertilization in vitro (IVF) bypasses the female oviduct and manually inseminates, fertilizes and cultivates embryos in a static microdrop containing appropriate chemical compounds. A microfluidic microchannel system for IVF is considered to provide an improved in-vivo-mimicking environment to enhance the development in a culture system for an embryo before implantation. We demons...

Degradation of maternally stored mRNAs after fertilization is an essential process for mammalian embryogenesis. Maternal mRNA degradation depending on deadenylases in mammalian early embryos has been mostly speculated, rather than directly demonstrated. Previously, we found that gene expression of nocturnin, which functions as a circadian clock-controlled deadenylase in mammalian cells, was cle...