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Wu-Chuang, A.

Publications and source records attributed to Wu-Chuang, A..

3 recordsLinked to original sources

Genome-wide CRISPR knockout cell screening platform for the disease vector tick species Ixodes scapularis

The black legged tick, Ixodes scapularis, is a vector of the bacterium that causes Lyme disease and several other illnesses, including anaplasmosis, babesiosis, and tick-borne encephalitis. Although high-quality genome annotations are available for I. scapularis, functional understanding of I. scapularis genes is limited. To address this, we developed a platform for genome-wide CRISPR-Cas9 knockout screening in I. scapularis cells. To evaluate the platform, we performed a screen to identify genes associated with cellular fitness, and screens for resistance to treatment with copper chloride, Antimycin A, or Destruxin A (DA), a cyclic hexadepsipeptide produced by the pathogenic fungus Metarhizium anisopliae. In each case, the screens implicate specific sets of conserved and non-conserved I. scapularis genes in relevant cellular functions, providing the first experimental evidence of function for a large set of I. scapularis genes. Altogether, in this first-of-its-kind effort for the arthropod subclass Acari, we present an unbiased genome-wide CRISPR-Cas9 knockout cell screening platform, related resources, and datasets that will be broadly useful to efficiently uncover cellular functions of I. scapularis genes.

genetics↗

Molecular dialogue between Orthonairovirus and tick: RNA-protein interactome of Hazara virus, a BSL2 model of Crimean-Congo Hemorrhagic Fever virus, in Hyalomma cells

Climate change and ecosystem collapse promote geographic expansion of vector-borne diseases, as witnessed by the recent incursions into Spain of the virus responsible for Crimean-Congo hemorrhagic fever (CCHFV). CCHFV is maintained in a tick-vertebrate cycle, principally involving ticks of the genus Hyalomma. Faced with the spread of Hyalomma ticks, and therefore the threat of a natural introduction of CCHFV into Western Europe, appropriate surveillance tools and control measures need to be implemented. It is both within and by the tick that CCHFV is maintained and spread in the environment. Despite prolonged portage of the virus, the tick is not overtly affected by CHFV infection. One of the prerequisites in conceiving control strategies is to understand the molecular mechanisms that intimately link the virus to its arthropod host. Despite the central role of the tick in the biology of CCHFV, these mechanisms are ill-defined, owing in part to the constraints associated with handling CCHFV-infected ticks in biosafety level 4 containment. In this study, we established the network of interactions between the S segment of the RNA genome Hazara virus (HAZV), a BSL-2 model of CCHFV, and Hyalomma proteins using ChIRP-MS technique. We identified 166 tick proteins, 21 of which have been described as RNA-binding proteins. Gene ontology and pathway enrichment analyses revealed that the S segment RNA interacts predominantly with mitochondrial proteins that belong to various mitochondrial metabolic pathways.

microbiology↗

Anti-microbiota vaccines modulate the tick microbiome in a taxon-specific manner

Anti-tick microbiota vaccines have been shown to impact tick feeding but its specificity has not been demonstrated. In this study we aimed to investigate the impact of immune targeting of keystone microbiota bacteria on tick performance, and tick microbiota structure and function. Vaccination against Escherichia coli, the selected keystone taxon, increased tick engorgement weight and reduced bacterial diversity in Ixodes ricinus ticks compared to those that fed on mice immunized against Leuconostoc mesenteroides, a non-keystone taxon or mock-immunized group. The abundance of Escherichia-Shigella, but not Leuconostoc was significantly reduced in ticks fed on E. coli-immunized mice and this reduction was correlated with a significant increase in host antibodies (Abs) of the isotype IgM and IgG specific to E. coli proteins. This negative correlation was not observed between the abundance of Leuconostoc in ticks and anti-L. mesenteroides Abs in mice. We also demonstrated by co-occurrence network analysis, that immunization against the keystone bacterium restructure the hierarchy of the microbial community in ticks and that anti-tick microbiota vaccines reduced the resistance of networks to directed removal of taxa. Functional pathways analysis showed that immunization with a live bacterial vaccine can also induce taxon-specific changes in the abundance of pathways. Our results demonstrated that anti-tick microbiota vaccines can modulate the tick microbiome and that the modification is specific to the taxon chosen for host immunization. These results guide interventions for the control of tick infestations and pathogen infection/transmission.

immunology↗