Generation and Care of Xenopus laevis and Xenopus tropicalis Embryos

Abstract

Robust and efficient protocols for fertilization and early embryo care of Xenopus laevis and Xenopus tropicalis are essential for experimental success, as well as maintenance and propagation of precious animal stocks. The rapid growth of the National Xenopus Resource has required effective implementation and optimization of these protocols. Here, we discuss the procedures used at the National Xenopus Resource, which we found helpful for generation and early upkeep of Xenopus embryos and tadpoles.

CRISPR/Cas9 mediated mutation of the mtnr1a melatonin receptor gene causes rod photoreceptor degeneration in developing Xenopus tropicalis

“…Sexually mature adult male and female Nigerian strain X. tropicalis were purchased from the NXR (RRID:SCR_013731, https ://www.mbl.edu/xenop us), and housed at the OUHSC facility adhering to the protocols described by McNamara et al 77 . Embryos were generated according the procedures described by Wlizla et al 78,79 . One-cell stage embryos were microinjected with 5 nl containing 500 ng of Cas9 protein complexed with 750 pg of both the T1 and T2 sgRNAs, with 0.1% Texas Red dextran.…”

“…They were transported as 2-week old tadpoles to our satellite aquatics facility at the University of Oklahoma Health Sciences Center (OUHSC). They were maintained in accordance with the established animal housing and procedure protocols at the NXR 77 , 78 , which were approved by the Institutional Animal Care and Use Committees at OUHSC and MBL. Sexually mature adult male and female Nigerian strain X. tropicalis were purchased from the NXR (RRID:SCR_013731, https://www.mbl.edu/xenopus ), and housed at the OUHSC facility adhering to the protocols described by McNamara et al .…”

“…Embryos were generated according the procedures described by Wlizla et al . 78 , 79 . One-cell stage embryos were microinjected with 5 nl containing 500 ng of Cas9 protein complexed with 750 pg of both the T1 and T2 sgRNAs, with 0.1% Texas Red dextran.…”

Xenopus leads the way: Frogs as a pioneering model to understand the human brain

“…Part of the reason that amphibians are a major model today is the richness of their history as a model system and the consequent deep understanding of their development that permits contextualization of ongoing discoveries. Over a century ago, experimentalists chose amphibian embryos, both anuran (frogs, including Xenopus ) and urodele (newts and salamanders), as the ideal candidates to develop and apply the embryological techniques necessary to answer central questions about animal development (Gurdon & Hopwood, 2000; Wlizla, McNamara, & Horb, 2018). The unique convergence of several appealing features of amphibian development made them the obvious choice at the time and is major strength to this day.…”

“…The unique convergence of several appealing features of amphibian development made them the obvious choice at the time and is major strength to this day. Intuitive among these are amphibian embryos' rapid, external, and robust development and large size; the large number of embryos that can be obtained from a single mating pair; the ability to induce mating year‐round in species including Xenopus ; and the cost‐effectiveness of animal care (Gurdon & Hopwood, 2000; McNamara, Wlizla, & Horb, 2018; Wlizla et al, 2018). Additionally, embryos can be cultured easily through all developmental stages in simple saline solution and are remarkably amenable to explant, transplant, and ablation techniques (Schoenwolf, 2001; Sive, Grainger, & Harland, 2000).…”