ANALYSIS OF HISTONES IN XENOPUS LAEVIS PART I: A DISTINCT INDEX OF ENRICHED VARIANTS AND MODIFICATIONS EXISTS IN EACH CELL TYPE AND IS REMODELED DURING DEVELOPMENTAL TRANSITIONS David Shechter*, Joshua J. Nicklay†, Raghu K. Chitta†, Jeffrey Shabanowitz†, Donald F. Hunt†°, and C. David Allis* *The Laboratory of Chromatin Biology, The Rockefeller University, New York, NY 10065; Department of †Che...

We have studied protein synthesis in the viable hybrid Xenopus laevis (female) X Xenopus borealis (male) using 2D gel electrophoresis. Fourteen borealis-specific proteins were studied. Two of these proteins appeared by the gastrula stage, five in the gastrula and the rest later. Where homologous laevis proteins were tentatively identified, androgenetic haploid hybrids were used to study whether...

FoxF genes are essential for visceral mesoderm development from Drosophila to human. However, part of the difficulty of studying the visceral mesoderm is its relative inaccessibility during early development. Owing to its external development Xenopus laevis presents considerable advantages for the study of visceral mesoderm formation, yet FoxF2 has not been identified in this system. Here, we d...

Cells in the prospective somite of Xenopus laevis embryos rotate in an orchestrated manner to form a segregated somite. The prospective somite boundaries are prepatterned by gene expressions in the unsegmented presomitic mesoderm (PSM). However, the roles of polarized gene expression in this boundary formation are not well elucidated. Here we identified a novel gene, bowline, which localizes to...

The widespread African clawed frog (Xenopus laevis) occurs in sympatry with the IUCN Endangered Cape platanna (Xenopus gilli) throughout its entire range in the south-western Cape, South Africa. In order to investigate aspects of the interspecific competition between populations of X. laevis and X. gilli, an assessment of their niche differentiation was conducted through a comprehensive study o...

Connexin-containing gap junctions play an essential role in vertebrate development. More than 20 connexin isoforms have been identified in mammals. However, the number identified in Xenopus trails with only six isoforms described. Here, identification of a new connexin isoform from Xenopus laevis is described. Connexin40.4 was found by screening expressed sequence tag databases and carrying out...

Here we report a new method of isolating epidermal desmosomes from Xenopus laevis, and a major constituent of desmosomes designated as Xenopus desmogleins (XDsg). Isolation of desmosomes from Xenopus laevis epidermis was carried out by a two step-incubation with different concentrations of NP-40. After discontinuous sucrose gradient centrifugation at 30,000 g for 60 min, a pure desmosomal fract...

Widespread and persistent marker expression is a prerequisite for many transgenic applications, including chimeric transplantation studies. Although existing transgenic tools for the clawed frog, Xenopus laevis, offer a number of promoters that drive widespread expression during embryonic stages, obtaining transgene expression through metamorphosis and into differentiated adult tissues has been...

Remarkable progress has recently been made in molecular biology of double axis formation in Xenopus laevis. Leaving aside, for the time being, the problem of the gene expressions regulating Xenopus laevis development, here I show that pulse treatment could induce formation of a secondary axis in a fertilized Xenopus laevis egg. At 3 min after insemination, metal oxides were added to Xenopus fer...