Knockout of Anopheles stephensi immune gene LRIM1 by CRISPR-Cas9 reveals its unexpected role in reproduction and vector competence

Autor: B. K. L. Sim, Abraham G. Eappen, Stephen L. Hoffman, Robert A. Harrell, Peter F. Billingsley, M. Hosseini, W. Reid, E. Inbar, Robert Alford, Sumana Chakravarty, Tao Li
Rok vydání: 2021
Předmět:
Male
Plasmodium
Physiology
Eggs
Artificial Gene Amplification and Extension
Disease Vectors
Mosquitoes
Polymerase Chain Reaction
Synthetic Genome Editing
Genome Engineering
Medical Conditions
Reproductive Physiology
Medicine and Health Sciences
Biology (General)
Reproduction
Crispr
Anopheles
Eukaryota
Fecundity
Body Fluids
Insects
Infectious Diseases
Blood
Insect Proteins
Engineering and Technology
Female
Synthetic Biology
Anatomy
Research Article
Arthropoda
QH301-705.5
Immunology
Bioengineering
Mosquito Vectors
Biology
Research and Analysis Methods
Microbiology
Population Metrics
Virology
Parasite Groups
parasitic diseases
Parasitic Diseases
Genetics
Animals
Microbiome
Molecular Biology Techniques
Molecular Biology
Gene
Anopheles stephensi
Bacteria
Population Biology
fungi
Organisms
Oocysts
Biology and Life Sciences
Plasmodium falciparum
RC581-607
Synthetic Genomics
biology.organism_classification
Invertebrates
PfSPZ vaccine
Malaria
Insect Vectors
Species Interactions
Parasitology
Immunologic diseases. Allergy
CRISPR-Cas Systems
Digestive System
Zoology
Entomology
Apicomplexa
Zdroj: PLoS Pathogens
PLoS Pathogens, Vol 17, Iss 11, p e1009770 (2021)
ISSN: 1553-7374
DOI: 10.1371/journal.ppat.1009770
Popis: PfSPZ Vaccine against malaria is composed of Plasmodium falciparum (Pf) sporozoites (SPZ) manufactured using aseptically reared Anopheles stephensi mosquitoes. Immune response genes of Anopheles mosquitoes such as Leucin-Rich protein (LRIM1), inhibit Plasmodium SPZ development (sporogony) in mosquitoes by supporting melanization and phagocytosis of ookinetes. With the aim of increasing PfSPZ infection intensities, we generated an A. stephensi LRIM1 knockout line, Δaslrim1, by embryonic genome editing using CRISPR-Cas9. Δaslrim1 mosquitoes had a significantly increased midgut bacterial load and an altered microbiome composition, including elimination of commensal acetic acid bacteria. The alterations in the microbiome caused increased mosquito mortality and unexpectedly, significantly reduced sporogony. The survival rate of Δaslrim1 mosquitoes and their ability to support PfSPZ development, were partially restored by antibiotic treatment of the mosquitoes, and fully restored to baseline when Δaslrim1 mosquitoes were produced aseptically. Deletion of LRIM1 also affected reproductive capacity: oviposition, fecundity and male fertility were significantly compromised. Attenuation in fecundity was not associated with the altered microbiome. This work demonstrates that LRIM1’s regulation of the microbiome has a major impact on vector competence and longevity of A. stephensi. Additionally, LRIM1 deletion identified an unexpected role for this gene in fecundity and reduction of sperm transfer by males.
Author summary The Leucin-Rich Protein LRIM1 is an important component of the complement-like cascade in Anopheles mosquitoes and was shown previously to have anti-parasitic activity, supporting melanization and phagocytosis of Plasmodium ookinetes. To improve the manufacturing of Sanaria’s PfSPZ vaccine, by increasing Pf infection intensity in the mosquitoes, we have generated an LRIM1 knockout line (Δaslrim1) using CRISPR-Cas9. Both bacterial load and the bacterial community composition altered significantly in Δaslrim1; these alterations were associated with reduced mosquito survival and, contrary to our expectations, dramatic reduction in Pf infection intensity. Reproductive capacity was reduced significantly in both females (fecundity) and males (fertility) of the Δaslrim1 line. Δaslrim1 mosquitoes cannot be used in the manufacturing of PfSPZ vaccine, but the data reveal novel and unexpected roles of LRIM1 in different aspects of the mosquitoes’ vectorial capacity, such as survival and reproduction. Importantly, our findings demonstrate the importance of LRIM1 in controlling the microflora in the mosquitoes and thereby allowing successful infection of the parasites.
Databáze: OpenAIRE