Expanding the genetic toolkit in Xenopus: Approaches and opportunities for human disease modeling.
The amphibian model Xenopus, has been used extensively over the past century to study multiple aspects of cell and developmental biology. Xenopus offers advantages of a non-mammalian system, including high fecundity, external development, and simple housing requirements, with additional advantages of large embryos, highly conserved developmental processes, and close evolutionary relationship to higher vertebrates. There are two main species of Xenopus used in biomedical research, Xenopus laevis and Xenopus tropicalis; the common perception is that both species are excellent models for embryological and cell biological studies, but only Xenopus tropicalis is useful as a genetic model. The recent completion of the Xenopus laevis genome sequence combined with implementation of genome editing tools, such as TALENs (transcription activator-like effector nucleases) and CRISPR-Cas (clustered regularly interspaced short palindromic repeats-CRISPR associated nucleases), greatly facilitates the use of both Xenopus laevis and Xenopus tropicalis for understanding gene function in development and disease. In this paper, we review recent advances made in Xenopus laevis and Xenopus tropicalis with TALENs and CRISPR-Cas and discuss the various approaches that have been used to generate knockout and knock-in animals in both species. These advances show that both Xenopus species are useful for genetic approaches and in particular counters the notion that Xenopus laevis is not amenable to genetic manipulations.
University of North Carolina McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3280, United States. Electronic address: ptandon@email.unc.edu.
Panna
P
Tandon
University of North Carolina McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3280, United States.
Frank
F
Conlon
Deparment of Neurobiology, Physiology and Behavior, University of California, Davis, CA 95616, United States.
J David
JD
Furlow
National Xenopus Resource and Eugene Bell Center for Regenerative Biology and Tissue Engineering, Marine Biological Laboratory, Woods Hole, MA 02543, United States. Electronic address: mhorb@mbl.edu.
Marko E
ME
Horb
D000822:Animal Husbandry / Q000458:organization & administration; D000818:Animals; D020029:Base Pairing; D064113:CRISPR-Cas Systems; D004195:Disease Models, Animal; D000072669:Gene Editing / Q000379:methods*; D055879:Gene Knock-In Techniques; D055786:Gene Knockout Techniques; D016678:Genome; D006801:Humans; D007756:Laboratory Animal Science / Q000458:organization & administration; D000068618:Selective Breeding; D057891:Tetraploidy; D000069896:Transcription Activator-Like Effector Nucleases; D014981:Xenopus / Q000235:genetics*; D014982:Xenopus laevis / Q000235:genetics
D000069896:Transcription Activator-Like Effector Nucleases
CRISPR-Cas; Human disease model; J strain; Knock-in; TALENs; Xenopus laevis; Xenopus tropicalis