Generation of no‐yellow‐pigment Xenopus tropicalis by slc2a7 gene knockout. Issue 10 (14th April 2021) - Nakajima, Keisuke
Abstract: Background: Amphibians possess three kinds of dermal chromatophore: melanophores, iridophores, and xanthophores. Knockout Xenopus tropicalis that lack the pigmentation of melanophores and iridophores have been reported. The identification of the causal genes for xanthophore pigmentation or differentiation could lead to the creation of a see‐through frog without three chromatophores. The genes causing xanthophore differentiation mutants are slc2a11b and slc2a15b in Japanese medaka ( Oryzias latipes ). Results: To obtain a heritable line of X tropicalis mutants without yellow pigment, we generated slc2a7 and slc2a15a knockout animals because they have the greatest similarity to the O latipes slc2a11b and slc2a15b genes. The slc2a7 knockout frog had a bluish skin and there were no visible yellow pigments in stereo microscope and skin section observations. Furthermore, no pterinosomes, which are characteristic of xanthophores, were observed via transmission electron microscopy in the skin of knockout animals. Conclusions: We report the successful generation of a heritable no‐yellow‐pigment X tropicalis mutant after knock out of the slc2a7 gene. This finding will enable the creation of a see‐through frog with no chromatophores. Key Findings: The knock out of slc2a7 gene of Xenopus tropicalis made it bluish skin color. There were no visible xanthophores, no yellow pigments and no visible pterinosomes. These findings make it possible to generate see‐through frog losing all three‐color pigments. Generation of no‐yellow‐pigment Xenopus tropicalis by the knockout of slc2a7 gene. This finding would enable to generate transparent Xenopus tropicalis. The transparent Xenopus tropicalis would be a useful tool for biology.