RESUMO
Exosomes are micro messengers encapsulating RNA, DNA, and proteins for intercellular communication associated with various physiological and pathological reactions. Several viral infection processes have been reported to pertain to exosomal pathways. However, because of the difficulty in obtaining avian-sourced exosomes, avian virus-related exosomes are scarcely investigated. In this study, we developed a protein A/G-correlated method and successfully obtained the Newcastle disease virus-related exosome (NDV Ex). These exosomes promoted NDV propagation, proven by both GW4869-mediated deprivation and exosomal supplementation. Viral structural proteins NP and F were detected in the NDV Ex and further investigation indicated that the NP protein can be transferred to DF-1â¯cells through exosomes. The intracellular NP protein exhibited viral replication-promoting and cytokine-suppressing abilities. Therefore, NDV infection produces exosomes, which transfer viral NP protein and promote NDV infection, emphasizing the importance of exosomes in an NDV infection.
Assuntos
Exossomos/metabolismo , Vírus da Doença de Newcastle/fisiologia , Vírus da Doença de Newcastle/patogenicidade , Estruturas Virais/isolamento & purificação , Estruturas Virais/metabolismo , Replicação Viral , Animais , Linhagem Celular , Galinhas , Citocinas/metabolismo , Humanos , Vírus da Doença de Newcastle/crescimento & desenvolvimento , Proteínas do Nucleocapsídeo , Nucleoproteínas/isolamento & purificação , Nucleoproteínas/metabolismo , Proteínas Recombinantes , Tetraspanina 28/genética , Tetraspanina 28/metabolismo , Tetraspanina 30/genética , Tetraspanina 30/metabolismo , Proteínas Virais de Fusão/isolamento & purificação , Proteínas Virais de Fusão/metabolismo , Proteínas Virais/genética , Proteínas Virais/isolamento & purificação , Proteínas Virais/metabolismoRESUMO
Complex Citrus tristeza virus (CTV) populations composed of mixtures of different strains of the virus are commonly found in citrus trees in the field. At present, little is known about how these populations are formed, maintained, and how they are structured within a host. Here we used a novel in situ hybridization approach allowing simultaneous visualization of two different RNA targets with high sensitivity and specificity to examine the distribution of two isolates, T36 and T68-1, representing phylogenetically distinct strains of CTV, in a citrus host in single and mixed infections. Remarkably, in doubly inoculated plants the two virus variants appeared to be well mixed within the infected tissue and showed no spatial segregation. In addition, both CTV variants were often found occupying the same cells. Possible mechanisms involved in shaping CTV populations and the biological significance of the observed lack of structural separation of the individual components are discussed.
Assuntos
Citrus/virologia , Closterovirus/isolamento & purificação , Hibridização In Situ/métodos , Doenças das Plantas/virologia , Closterovirus/classificação , Closterovirus/genética , Variação Genética , Genótipo , Filogenia , RNA Viral/genética , Estruturas Virais/classificação , Estruturas Virais/genética , Estruturas Virais/isolamento & purificaçãoRESUMO
We present the first attempt at quantitative analysis of morphological diversity of tailed viruses obtained from marine sediments without ultracentrifugation or enrichment on specific host strains. Sandy mud samples were collected in the Gulf of Gdansk in the spring, autumn and winter. VLPs were analyzed by transmission electron microscopy. The distribution of three groups of tailed phages was similar in all seasons (Siphoviridae: 52% on average; Myoviridae: 42%; Podoviridae: 6%). 19% of siphoviruses had prolate heads. Interestingly, 11% of siphoviral particles had tails longer than 300 nm, and 6% longer than 600 nm.