Chloroplasts play crucial roles in plant defence against viral infection. We now report that chloroplast NADH dehydrogenase-like (NDH) complex M subunit gene ( NdhM ) was first up-regulated and then down-regulated in turnip mosaic virus (TuMV)-infected N. benthamiana . NbNdhM -silenced plants were more susceptible to TuMV, whereas overexpression of NbNdhM inhibited TuMV accumulation. Overexpression of NbNdhM significantly induced the clustering of chloroplasts around the nuclei and disturbing this clustering facilitated TuMV infection, suggesting that the clustering mediated by NbNdhM is a defence against TuMV. It was then shown that NbNdhM interacted with TuMV VPg, and that the NdhMs of different plant species interacted with the proteins of different viruses, implying that NdhM may be a common target of viruses. In the presence of TuMV VPg, NbNdhM, which is normally localized in the nucleus, chloroplasts, cell periphery and chloroplast stromules, colocalized with VPg at the nucleus and nucleolus, with significantly increased nuclear accumulation, while NbNdhM-mediated chloroplast clustering was significantly impaired. This study therefore indicates that NbNdhM has a defensive role in TuMV infection probably by inducing the perinuclear clustering of chloroplasts, and that the localization of NbNdhM is altered by its interaction with TuMV VPg in a way that promotes virus infection.
Michelia belongs to Magnoliaceae and has important timber, medicinal, oil and ornamental values. The wide morphological variation of this genus and the hybridization among some species make it difficult to classify. There are controversies about the systematic relationships and status of species within the genera. In this communication, we have made the first taxonomic survey of species of the genus Michelia using electrochemical fingerprinting. The molecules corresponding to the oxidation peaks in the electrochemical fingerprints were explored. The electrochemical fingerprints collected under different conditions were used to construct density pattern. Texture features and local binary pattern algorithms are used to the identification of different species. The results of the phylogenetic tree generated based on electrochemical fingerprinting differed significantly from those of traditional morphological taxonomy. However, these results are in good agreement with the phylogenetic trees generated by chloroplast sequencing.
危险品化学品经营许可证（带存储）