What is gastrulation Xenopus?
Xenopus gastrulation movements are in large part based on the rearrangement of cells by differential cell-on-cell migration within multilayered tissues. Different patterns of migration-based cell intercalation drive endoderm and mesoderm internalization and their positioning along their prospective body axes.
What is a Xenopus tadpole?
Xenopus laevis tadpoles that arrest development and remain as larvae for several years sometimes occur spontaneously in laboratory populations. These tadpoles cease development at an early hindlimb stage, but continue to grow and develop into grossly deformed giants.
Which germ layer is formed by cells at the animal pole of a Xenopus embryo?
At the end of gastrulation, the Xenopus embryo becomes known as a gastrula. It has an ectoderm as its outermost layer, and an endoderm as its innermost layer.
How many cells does a Xenopus embryo undergoing ZGA have?
(Ac) At the mid-blastula stage, the embryo consists of 4000 cells, gap phases reappear, the cycle lengthens to 50 minutes and zygotic gene expression commences.
What is Xenopus blastula?
The blastula stage embryo is a ball of cells surrounding a fluid filled cavity, the blastocoel, which is displaced to the animal hemisphere by the large, yolk rich, vegetal blastomeres. Fate. maps have shown that the animal hemisphere will form the. ectoderm, while the vegetal hemisphere will form the.
What is the symmetry breaking event in the specification of the Xenopus animal vegetal axis?
One of the most studied examples is the cortical rotation during Xenopus development, where this rotation acts as the symmetry-breaking event that determines the dorsal-ventral axis of the developing embryo.
What is Xenopus laevis used for?
Abstract. Xenopus laevis has long been a popular model for studies of development and, based on the use of cell-free extracts derived from its eggs, as a model for reconstitution of cell cycle regulation and other basic cellular processes.
Why are Xenopus laevis used in research?
laevis for genetic studies because it only has two copies of every chromosome compared to X. laevis which has four copies. Genetically, Xenopus are very similar to humans and are therefore a good model for human disease.
Are Xenopus vertebrates?
Thus, Xenopus is a vertebrate model system that allows for high-throughput in vivo analyses of gene function and high-throughput biochemistry. Furthermore, Xenopus oocytes are a leading system for studies of ion transport and channel physiology.
What is axis formation amphibians?
Amphibian axis formation is an example of regulative development. In Chapter 3, we discussed the concept of regulative development, wherein (1) an isolated blastomere has a potency greater than its normal embryonic fate, and (2) a cell’s fate is determined by interactions between neighboring cells.
Why cortical rotation is important for Xenopus development?
Abstract. We first review cortical-cytoplasmic rotation, a microtubule-mediated process by which the Xenopus egg, like other amphibian eggs, transforms its polarized cylindrical symmetry into bilateral symmetry within the first cell cycle after fertilization.
Is Xenopus easy to use?
Because the Xenopus embryos develop outside of the body they can easily be surgically manipulated or treated with proteins and chemicals that interfere with development. X. tropicalis is a simpler model than X. laevis for genetic studies because it only has two copies of every chromosome compared to X.