Zhai Runliang, Chang Liming, Jiang Jianping, Wang Bin, Zhu Wei
Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610213, China.
University of Chinese Academy of Sciences, Beijing 101408, China.
Animals (Basel). 2024 Dec 1;14(23):3472. doi: 10.3390/ani14233472.
Background color matching is essential for camouflage and thermoregulation in ectothermic vertebrates, yet several key cellular-level questions remain unresolved. For instance, it is unclear whether the number of chromatophores or the activity of individual chromatophores plays a more critical role in this process. Using single-cell RNA sequencing (scRNA-seq), we investigated the cellular and molecular mechanisms underlying color change in , which adapted to its background by displaying light-green skin on white and black skin on black within two days. We identified two types of chromatophores in their skin, both responsible for the observed color differences. Our findings reveal that morphological color change (MCC) is the dominant process, with the number of chromatophores being more influential in driving color change than the transcriptional activity of melanogenesis in individual cells. Additionally, melanophores from darker individuals exhibited increased activity in energy metabolism pathways, while those from lighter individuals showed stronger immune-related gene expression, suggesting that background adaptation involves more than just morphological changes. Overall, this study successfully applied single-cell sequencing technology to investigate skin pigmentation in a non-model organism. Our results suggest that MCC driven by chromatophore proliferation is a key mechanism of background adaptation, offering new insights into amphibian color adaptation and environmental adaptation in other vertebrates.
背景颜色匹配对于变温脊椎动物的伪装和体温调节至关重要，但几个关键的细胞水平问题仍未得到解决。例如，尚不清楚色素细胞的数量或单个色素细胞的活性在这一过程中哪个发挥更关键的作用。我们使用单细胞RNA测序（scRNA-seq），研究了 变色的细胞和分子机制，它能在两天内通过在白色背景上呈现浅绿色皮肤以及在黑色背景上呈现黑色皮肤来适应其背景。我们在其皮肤中鉴定出两种色素细胞，它们都对观察到的颜色差异负责。我们的研究结果表明，形态颜色变化（MCC）是主要过程，色素细胞的数量在驱动颜色变化方面比单个细胞中黑色素生成的转录活性更具影响力。此外，来自颜色较深个体的黑素细胞在能量代谢途径中表现出更高的活性，而来自颜色较浅个体的黑素细胞则表现出更强的免疫相关基因表达，这表明背景适应不仅仅涉及形态变化。总体而言，本研究成功应用单细胞测序技术研究了一种非模式生物的皮肤色素沉着。我们的结果表明，由色素细胞增殖驱动的MCC是背景适应的关键机制，为两栖动物颜色适应及其他脊椎动物的环境适应提供了新的见解。
