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The H5N6 avian influenza virus (AIV) is constantly undergoing recombination and evolution with other subtypes of AIV, resulting in various types of recombinant H5N6 viruses. However, the risk to human public health of different recombinant types of H5N6 viruses remains unclear. Recently, two types of different recombinant H5N6 viruses were isolated from chickens. One of the viruses possessed six internal genes originating from H9N2, named A/Chicken/Hubei/112/2020 (H5N6) (abbreviated 112); the other virus possessed PB2, PB1, PA, and NP originating from H5N1, while the M and NS genes were derived from H9N2, named A/Chicken/Hubei/125/2020 (H5N6) (abbreviated 125). Here, we investigated the receptor binding properties, pathogenicity, and transmissibility of the two H5N6 AIVs. The results showed that 112 and 125 could bind α‐2,3‐linked sialic acid receptor (avian‐like receptor) and α‐2,6‐linked sialic acid receptor (human‐like receptor). However, 125 and 112 showed different pathogenicity in mice. Mice infected with 125 lost only a slight body weight and all survived, while mice infected with 112 lost weight rapidly and all died within a week of infection. Furthermore, in the transmission experiment, 125 could only transmit through direct contact, while 112 could transmit not only by direct contact but also by aerosol. The above results indicated that 112 exhibited enhanced pathogenicity and transmissibility compared to 125, suggesting that the H5N6 virus, whose internal genes were derived from H9N2, could pose a greater threat to human health. Therefore, continuous monitoring of different recombinant H5N6 viruses in poultry should be carried out to prevent their transmission to humans. [ABSTRACT FROM AUTHOR]

Leucine-rich repeat extensin (LRX) is involved in the regulation of crucial cellular processes, such as cell wall growth and development, as well as signaling. However, the presence of the LRX gene family in Brassica rapa (B. rapa) has not been previously reported. This study identified 17 BrLRXs within the Brassica rapa genome by bioinformatic analysis, and these genes were distributed on seven chromosomes. Phylogenetic and covariance analyses indicate that BrLRXs can be categorized into two distinct branches: the trophic branch and the reproductive branch, with a close relationship observed between BrLRXs and AtLRXs. According to cis-acting element analysis, this gene family is rich in hormone-responsive and stress-responsive elements such as drought-inducibility, abscisic acid, methyl jasmonate, and gibberellic acid responsive elements, suggesting a potential role in abiotic stress response. Transcriptomic, proteomic, and RT-qPCR analyses demonstrated significant up-regulation of BrLRX2 and BrLRX6 under salt stress, while BrLRX3, BrLRX6, and BrLRX8 were significantly down-regulated under osmotic stress. Our analysis of the protein tertiary structure predicts a strong association between LRX proteins and RALF. Protein–protein interaction prediction revealed that LRX interacts with the RALF protein and the receptor FER, which have been previously reported to jointly regulate plant stress responses. We propose that BrLRX6 and BrLRX8 are implicated in osmotic stress, while BrLRX2 and BrLRX6 are involved in the modulation of salt stress. [ABSTRACT FROM AUTHOR]

Fusarium oxysporum f. sp. radicis-lycopersici (Forl) is a destructive soil-borne phytopathogenic fungus that causes Fusarium crown and root rot (FCRR) of tomato, leading to considerable field yield losses. In this study, we explored the antifungal capability of linalool, a natural plant volatile organic component, against Forl and its role in controlling FCRR symptoms in tomatoes. Our results showed that Forl mycelial growth was inhibited by the linalool treatment and that the linalool treatment damaged cell membrane integrity, enhanced reactive oxygen species levels, depleted glutathione, and reduced the activities of many antioxidant enzymes in Forl. Transcriptomic and proteomic analyses demonstrated that linalool also downregulated metabolic biosynthetic pathways at the transcript and protein levels, including redox, transporter activity, and carbohydrate metabolism in Forl. Moreover, linalool significantly decreased the expression of many Forl pathogenic genes, such as cell wall degrading enzymes (CWDEs) and G proteins, which is likely how a Forl infection was prevented. Importantly, exogenously applied linalool activated the salicylic acid (SA) and jasmonic acid (JA) defensive pathways to improve disease resistance and relieved the negative effects of Forl on plant growth. Taken together, we report that linalool is an effective fungicide against Forl and will be a promising green chemical agent for controlling FCRR. [ABSTRACT FROM AUTHOR]