Cell differentiation depends mainly on specific mRNA expression. To quantify the expression of a particular gene, the normalisation with respect to the expression of a reference gene is carried out. This is based on the assumption that the expression of the reference gene is constant during development, in different cells or tissues or after treatment. Xenopus laevis studies have frequently use...

The intracellular localisation and mobility of exogenous DNA introduced into Xenopus laevis oocytes is largely unknown. In this paper, we report a new technique to investigate the cytoplasmic/nuclear transport of a random pool of linear, double-stranded, oligomeric DNA of 147 bp in length. We chose a combinatorial approach which made use of repetitive rounds of selection and amplification to se...

Introduced species can arrive into new territories with parasites; however, these species are expected to face lower parasite richness than in their original regions. Both introduced hosts and parasites can affect native fauna. Since their release into the wild in Chile following laboratory use, Xenopus laevis Daudin, 1802 has widely spread throughout central Chile. The only pathogen described ...

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...

There is growing concern over the effect of sperm cryopreservation on DNA integrity and the subsequent development of offspring generated from this cryopreserved material. In the present study, membrane integrity and DNA stability of Xenopus laevis and Xenopus tropicalis spermatozoa were evaluated in response to cryopreservation with or without activation, a process that happens upon exposure t...

Using immunohistochemistry and western blot analysis, we demonstrate that melanopsin is localised in cells around the central pore of lateral line neuromasts in the African clawed frog, Xenopus laevis. Since melanopsin is a known photoreceptor pigment with diverse functions in vertebrates, we suggest that the lateral line of Xenopus laevis, which is primarily a mechanoreceptor, might also be li...

Appropriately-sized oocytes from Xenopus laevis can be grown in vitro in vitellogenin-containing serum for up to 2 weeks. The source of serum appears to be unimportant. Rates of oocyte growth are somewhat better than those achieved in the presence of vitellogenin alone. Rana pipiens oocytes grow about twice as fast as X. laevis oocytes under identical conditions. The oocyte culture conditions d...

(2798) Cistus laevis Cav., Icon. 2: 35. Apr–Nov 1793 [Angiosp.: Cist.], nom. cons. prop. Typus: [Spain, Valencia], “in montibus Enguerae et in Collado de Bocayrente”, 30 Jul 1791, Cavanilles (MA barcode MA 475536 [2 right-hand and 2 left-hand fragments, excl. central fragment]). (=) pilosus L., Sp. Pl.: 528. 1 Mai 1753, rej. Lectotypus (hic designatus): Herb. Burser XXIV: 66 (UPS No. V-175838)....