Ju Zhang, Zihan Ding, Peng-fei Wu, Wei-Guo Du, Yueqiang Guan, Xi-feng Wang. 2024. Disentangling the molecular mechanisms of yellow body coloration in a soft-shelled turtle. Zoological Research. DOI: 10.24272/j.issn.2095-8137.2024.276
Citation:
Ju Zhang, Zihan Ding, Peng-fei Wu, Wei-Guo Du, Yueqiang Guan, Xi-feng Wang. 2024. Disentangling the molecular mechanisms of yellow body coloration in a soft-shelled turtle. Zoological Research. DOI: 10.24272/j.issn.2095-8137.2024.276
Ju Zhang, Zihan Ding, Peng-fei Wu, Wei-Guo Du, Yueqiang Guan, Xi-feng Wang. 2024. Disentangling the molecular mechanisms of yellow body coloration in a soft-shelled turtle. Zoological Research. DOI: 10.24272/j.issn.2095-8137.2024.276
Citation:
Ju Zhang, Zihan Ding, Peng-fei Wu, Wei-Guo Du, Yueqiang Guan, Xi-feng Wang. 2024. Disentangling the molecular mechanisms of yellow body coloration in a soft-shelled turtle. Zoological Research. DOI: 10.24272/j.issn.2095-8137.2024.276
Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences
Bei-chen west road, chinese acdemy of science
Institute of Zoology, Chinese Academy of Sciences
Hebei University
Funds: National Natural Science Foundation of China (32020013); Project of Hebei Agricultural Innovation Team of Freshwater Aquaculture (Grant number: HBCT2023230204)
The functions of body coloration have been well characterized in many animal taxa, whereas the molecular mechanisms of its production remain poorly understood. Taking advantage of a mutant strain of Yongzhang golden soft-shelled turtles (Pelodiscus sinensis) (YGTs) with bright yellow body color, we identified specific molecular mechanisms underlying a yellow body coloration in a reptile. We found that YGTs exhibited lower melanin and higher carotenoid pigmentation than atrovirens wild-type turtles (AWTs), while the concentration of pterin in YGT was not higher than that in AWT. Functional validation experiments revealed that a single amino acid substitution (I481R) in tyrosinase-related protein 1 (tyrp1) plays a pivotal role in the reduction of melanin production in YGTs. We expressed tyrp1 from YGT and AWT in A375 cells in which the human tyrp1 (htyrp1) function had been depleted by CRISPR-Cas9 and observed a specific reduction of melanin in the cells with YGT-tyrp1. Moreover, bco1/bco2 expression, which is negatively associated with carotenoid content, was reduced in YGT. These results suggest that the yellow coloration is achieved through a reduction in melanin pigmentation combined with an accumulation of carotenoids in the YGTs, providing a molecular explanation for the production of yellow color. Our study not only provides the first piece of functional evidence for the role of pigments in yellow body coloration in turtles, but also improves our understanding of the molecular mechanism of yellow body coloration in vertebrates.