The epidermal barrier is important for the defense of environmental organisms against the damage from engineered nanomaterials (ENMs). We employed Caenorhabditis elegans to examine the possible influence of a deficit in the epidermal barrier caused by RNA interference (RNAi) knockdown of unc-52 encoding a perlecan protein on the toxicity of graphene oxide (GO). Epidermal RNAi knockdown of unc-52 caused a functional deficit in the epidermal barrier and susceptibility to GO toxicity. Epidermal knockdown of unc-52 decreased the level of expression of fbl-1 encoding a membrane protein fibulin and sax-7 encoding a cell adhesion receptor, and epidermal knockdown of fbl-1 or sax-7 also resulted in a functional deficit in the epidermal barrier and susceptibility to GO toxicity. Additionally, epidermal knockdown of unc-52 inhibited expression of cnc-2 and prx-11 encoding two antimicrobial proteins, and epidermal knockdown of cnc-2 or prx-11 could strengthen the GO toxicity in fbl-1(RNAi) or sax-7(RNAi) nematodes. Our data further highlight the important function of the epidermal barrier against toxicity of environmental ENMs.

中文翻译：

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氧化石墨烯在线虫中的毒性，由于unc-52的RNA干扰敲低导致表皮屏障不足。

表皮屏障对于保护环境生物免受工程纳米材料（ENM）的损害很重要。我们采用秀丽隐杆线虫检查表皮屏障缺陷的可能影响，该缺陷是由编码Perlecan蛋白的unc-52的RNA干扰（RNAi）敲低引起的，对氧化石墨烯（GO）的毒性具有影响。unc-52的表皮RNAi敲低导致表皮屏障的功能缺陷和对GO毒性的敏感性。unc-52的表皮基因敲低降低了编码膜蛋白纤蛋白的fbl-1和编码细胞粘附受体的sax-7的表达水平，而fbl-1的表皮抑制Sax-7或sax-7也会导致表皮屏障的功能缺陷和对GO毒性的敏感性。此外，unc-52的表皮基因敲低抑制了编码两种抗菌蛋白的cnc-2和prx-11的表达，而cnc-2或prx-11的表皮基因敲除可以增强fbl-1（RNAi）或sax-7的GO毒性。（RNAi）线虫。我们的数据进一步强调了表皮屏障对环境ENM毒性的重要作用。