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From 2012.igem.org

Xenopus: A model for biomedical research

Xenopus is a genus that includes several amphibian species of the family Pipidae species and both natives of Africa. Among many species, the best known are Xenopus laevis and Xenopus tropicalis. These two species of Xenopus are commonly studied and used by biologists as a model organism. This animal is widely used due to its powerful combination of experimental and traceability and its evolution similar to that of humans, at least compared to many model organisms. Xenopus is also an important tool for in vivo studies at the molecular, cellular and developmental biology of vertebrates. The wide range of used Xenopus research comes from the fact that most cell-free extracts made from Xenopus are the first in vitro system for the study of fundamental aspects of cellular and molecular biology. Thus, Xenopus is part of the only vertebrate model systems that allow high throughput in vivo analysis of gene function.

Xenopus laevis

X. laevis has been the first one widely used to investigate the early period of embryonic development. This is allowed due to its very rapid life cycle. Few days after the fertilization of female frog eggs, embryos develop in tadpoles with well-characterized organs. The rapid development cycle allows experiments on the embryos directly following fertilization. Embryos are commonly developed in saline solution.

xenbase.org
Even though X. laevis doesn’t have the shorter generation time and genetic simplicity generally desired in genetic of model organisms, it is an important one in developmental biology, cell biology, toxicology and neurobiology. It takes between one to two years to reach sexual maturity and it is a tetraploid organism, contrary to tropicalis which is a diploid.

Xenopus tropicalis

X. tropicalis is known to have a shorter cycle life than X. laevis. It’s now used as complement studies of X. laevis and aims to extend research into new areas. These areas that many researchers are involved in are morphogenesis and organogenesis. They both play an important role in medicine. Moreover, due to the efficient technique for transgenesis and the rapid development of this species, researches can easily engineer transgenic cell lines in X. tropicalis. Bioengineering of X. tropicalis with the tools of system biology is part of different projects lead around the world. It includes the Metamorphosis group of the Institute of Systems and Synthetic Biology in Evry, France.

Metamorphosis, iSSB
Basically, the project aims to “explore the fundamentals of genome structure and expression”. The team intends by at the same to “provide molecular genetics, transgenesis, transcriptomics and bioinformatic tools to study an easily amenable animal mode”.

Finally, contrary to zebrafish, Xenopus stands out as a major contributor to the understanding of the metabolome of cells, as well as chromosome replication and intracellular signaling.