Search results for "Blastula"
showing 4 items of 24 documents
Histones and non-histone proteins during sea urchin development
1979
Abstract Chromatin from blastulae and plutei of Paracentrotus lividus was fractionated through a hydroxyapatite column. The ratio of histones versus non-histone proteins decreases from blastula to pluteus stage.
The increase in maternal expression of axin1 and axin2 contribute to the zebrafish mutant ichabod ventralized phenotype.
2014
β-Catenin is a central effector of the Wnt pathway and one of the players in Ca(+)-dependent cell-cell adhesion. While many wnts are present and expressed in vertebrates, only one β-catenin exists in the majority of the organisms. One intriguing exception is zebrafish that carries two genes for β-catenin. The maternal recessive mutation ichabod presents very low levels of β-catenin2 that in turn affects dorsal axis formation, suggesting that β-catenin1 is incapable to compensate for β-catenin2 loss and raising the question of whether these two β-catenins may have differential roles during early axis specification. Here we identify a specific antibody that can discriminate selectively for β-…
Study on b-Catenins mechanisms of regulation in zebrafish blastula embryo
2012
Background: â-catenin is a central component of the cadherin cell adhesion complex but also it plays an essential role in the canonical-Wingless/Wnt signaling pathway. In vertebrates, one of the initial steps for the establishment of the correct dorso-ventral (D/V) pattern in the embryo is the cytoplasmic accumulation followed by nuclear localization of â-catenin in the cells of the prospective dorsal side of the embryo. In zebrafish there are two â-catenins, 92,7% identical. The mutant fish line Ichabod (ich), with a mutation in the region of the â-catenin2 promoter that causes a decrease in the maternal accumulation of â-catenin2 protein in the embryos, fail to nuclear localize â- catenin…
Cytochrome oxidase activity in the mitochondria of unfertilized and fertilized sea urchin eggs
1959
Abstract The cytochrome oxidase activity of isolated mitochondria of unfertilized and fertilized eggs of Paracentrotus lividus has been studied. It has been found that whereas in the mitochondria of unfertilized eggs saturation is reached at a cytochrome c concentration of 3.28 × 10−5 M, in those of fertilized eggs this occurs at a concentration of 5.74 × 10−5 M. It is shown that upon fertilization an increase of about 30 per cent of the activity of cytochrome oxidase takes place and no further changes appear to occur until blastula stage.