Virulent Newcastle disease virus (NDV) is a violent infection in avian species. The understanding of its pathogenic mechanism is consistently evolving along with the development of molecular biological advancement. Exosomes derived from NDV infected cells (NDV Ex) were reported to promote virus replication through transportation of viral proteins and miRNAs. However, the function of mRNAs in NDV Ex remains unknown. In this study, a novel mechanism of NDV Ex to facilitate NDV infection was explored. Through transcriptome analysis, seven immune related genes were found to up-regulate in NDV Ex. Among them, NLRX1 mRNA was notably enriched in NDV Ex, and decreased inside the cells after virulent NDV infection. Further investigation suggested that NLRX1 mRNA decrease was in accordance with the NLRX1 protein expression reduction. This process can be reversed by the inhibition of exosome release. Therefore, NDV infection could utilize NDV Ex to export NLRX1 mRNA and reduce cellular NLRX1 protein. As NLRX1 is a crucial anti-viral protein of MAVS signal pathway, and NDV Ex transported NLRX1 cannot counteract its function in recipient cells, it can be concluded that NDV could benefit its replication through exporting NLRX1 mRNA to relieve the anti-viral pressure on its survival.

强毒新城疫病毒 (NDV) 是禽类中的一种猛烈感染。随着分子生物学的进步，对其致病机制的认识也在不断发展。据报道，来自 NDV 感染细胞 (NDV Ex) 的外泌体通过病毒蛋白和 miRNA 的运输促进病毒复制。然而，NDV Ex 中 mRNA 的功能仍然未知。在这项研究中，探索了一种新的 NDV Ex 促进 NDV 感染的机制。通过转录组分析，发现七个免疫相关基因在 NDV Ex 中上调。其中，NLRX1 mRNA 在 NDV Ex 中显着富集，并在 NDV 毒力感染后细胞内减少。进一步的研究表明 NLRX1 mRNA 的减少与 NLRX1 蛋白表达的减少一致。这个过程可以通过抑制外泌体释放来逆转。因此，NDV感染可以利用NDV Ex输出NLRX1 mRNA并减少细胞NLRX1蛋白。由于 NLRX1 是 MAVS 信号通路的关键抗病毒蛋白，而 NDV Ex 转运的 NLRX1 不能抵消其在受体细胞中的功能，因此可以得出结论，NDV 可以通过输出 NLRX1 mRNA 以减轻其抗病毒压力来促进其复制。生存。