Department of Biochemistry, Indian Institute of Science, Bengaluru, 560012 Karnataka, India.
Biol Lett. 2020 Oct;16(10):20200391. doi: 10.1098/rsbl.2020.0391. Epub 2020 Oct 14.
Naturally occurring fluorescence has been observed in multiple species ranging from bacteria to birds. In macroscopic animals such as birds, fluorescence provides a visual communication signal. However, the functional significance of this phenomenon is unknown in most cases. Though photoprotection is attributed to fluorescence under ultraviolet (UV) light in some organisms, it lacks direct experimental evidence. Here, we demonstrate naturally occurring fluorescence under UV light in a eutardigrade belonging to the genus . Using a natural variant that lacks fluorescence, we show that the fluorescence confers tolerance to lethal UV radiation. Remarkably, the fluorescent extract from sp. could protect the UV-sensitive tardigrade and nematode from germicidal UV radiation. We propose that sp. possess a protective fluorescent shield that absorbs harmful UV radiation and emits harmless blue light.
在从细菌到鸟类的多种物种中都观察到了自然发生的荧光。在鸟类等宏观动物中，荧光提供了一种视觉通讯信号。然而，在大多数情况下，这种现象的功能意义尚不清楚。尽管在一些生物体中，荧光在紫外线 (UV) 光下提供了光保护作用，但这缺乏直接的实验证据。在这里，我们在属于 属的水熊虫中证明了在紫外线照射下自然发生的荧光。利用缺乏荧光的天然变体，我们表明荧光赋予了对致死紫外线辐射的耐受性。值得注意的是，来自 sp. 的荧光提取物可以保护对紫外线敏感的缓步动物 和线虫 免受杀菌紫外线辐射。我们提出， sp. 拥有一个保护性的荧光护盾，可以吸收有害的紫外线并发射无害的蓝光。
