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Li, X. y.

Publications and source records attributed to Li, X. y..

2 recordsLinked to original sources

CRISPR-Cas12a-Based Rapid and Sensitive Detection of rpoBL378R in Mycobacterium tuberculosis

Rifampin is the most effective drug in the treatment of tuberculosis, whose major pathogen is Mycobacterium tuberculosis (MTB), whereas there are still certain MTB strains resistant to the therapy of rifampin. The rpoB mutations play a central role in MTB resistance to the rifampin therapy, so it is crucial to identify these mutations in order to discover novel therapeutic approaches to these drug-resistant MTB strains. Here we show that a CRISPR-Cas12a-based detection platform with recombinase polymerase amplification and fluorescence reporter can be utilized to detect and visualize an MTB drug-resistant point mutation (rpoBL378R) from its rpoB wild type. Notably, this detection system is highly specific because it did not cross-react with contrived reference samples containing the genomes of MTB H37Rv, Mycobacterium smegmatis (M. smegmatis), Mycobacterium aureus (M. aureus), and Escherichia coli (E. coli). Collectively, this strategy based on CRISPR-Cas12a that we show in this report is simple, sensitive as well as specific for detection of the rifampin-resistant MTB H37Rv with the rpoBL378R mutation, indicating that this CRISPR-Cas12a-based detection platform has high potential to be exploited for clinic application to identify MTB mutations.

microbiology↗

Host protein CD63 enhances viral RNA replication by interacting with human astrovirus nonstructural protein nsP1a/4

Human astrovirus nonstructural protein nsP1a/4, located at the C-terminal end of nsP1a, is thought to be involved in the regulation of RNA replication and capsid maturation;however, its rolesviral growth and virulence are not well understood. We investigated the intracellular host proteins that interact with nsP1a and explored the potential roles of the interaction in the pathogenesis of human astrovirus infection. We screened 14 independent proteins with a cDNA library derived from Caco-2 cells using a yeast two-hybrid technique. Deletion analysis revealed that interaction between the nsP1a/4 domain and the large extracellular loop (LEL) domain of the human protein CD63 is necessary for astrovirus replication. The interaction was confirmed by glutathione-S-transferase (GST) pull-down assays and co-immunoprecipitation assays. Confocal microscopy showed that nsP1a/4 and CD63 co-localized in the cytoplasm of infected cells. Over expression of CD63 promoted viral RNA synthesis, whereas knockdown of CD63 markedly decreased viral RNA levels. Those results suggest that CD63 plays a critical role in human astrovirus RNA replication. The interaction between CD63 and nsP1a/4 provides a channel to further understand the roles of interactions between host and virus proteins in astrovirus infection and release.\n\nIMPORTANCEHuman astroviruses cause gastroenteritis in young children and immunocompromised patients. In this study, we provide evidence that nsP1a/4, a nonstructural protein located at the C-terminal end of the human astrovirus nsP1a polyprotein, interacts with the host protein CD63. Over expression of CD63 promoted viral RNA replication, whereas knockdown of CD63 decreased virus RNA replication, indicating that CD63 plays a critical role in the human astrovirus life cycle.

microbiology↗