Kassandra Durazo-Martínez , Jayeshbhai Chaudhari , Luke M. Sherry , Dennis A. Webster , Kyra Martins , Jonathan R. Bostrom , Daniel F. Carlson , Tad S. Sonstegard , Hiep L.X. Vu
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引用次数: 0
Abstract
CD163 is the primary receptor for PRRSV, and its SRCR5 domain, encoded by exon 7, is crucial for supporting PRRSV infection. Previous studies have used CRISPR/Cas9 technology to remove exon 7 from the host genome, and the edited pigs were completely resistant to PRRSV infection. In this study, we used CRISPR/Cas9 technology mimicking an adenine base editor (ABE) to edit the splice acceptor site of exon 7, rendering it nonfunctional. This alteration was intended to cause exon 6 to join directly to exon 8 during mRNA processing, resulting in a mature mRNA transcript that lacks exon 7, which encodes the SRCR5 domain. Piglets carrying the exon 7 splice site modification (CD163Ex7-ABE) were successfully generated. However, these pigs remained fully susceptible to infection with a PRRSV-2 isolate. Analysis of CD163 mRNA from the CD163Ex7-ABE pigs revealed that they predominantly expressed a mature CD163 mRNA lacking exon 7. However, due to cryptic splice sites, two additional mRNA isoforms were expressed, including an in-frame variant containing all of exon 7 and an extra 48 base pairs. This likely resulted in the expression of a full-length CD163 with a 16-amino-acid insertion upstream of the SRCR5 domain, which was sufficient to render the animals susceptible to PRRSV. Overall, our results demonstrate that merely modifying the splice acceptor site of CD163 exon 7 is not sufficient to generate PRRSV-resistant pigs.
期刊介绍:
Veterinary Microbiology is concerned with microbial (bacterial, fungal, viral) diseases of domesticated vertebrate animals (livestock, companion animals, fur-bearing animals, game, poultry, fish) that supply food, other useful products or companionship. In addition, Microbial diseases of wild animals living in captivity, or as members of the feral fauna will also be considered if the infections are of interest because of their interrelation with humans (zoonoses) and/or domestic animals. Studies of antimicrobial resistance are also included, provided that the results represent a substantial advance in knowledge. Authors are strongly encouraged to read - prior to submission - the Editorials (''Scope or cope'' and ''Scope or cope II'') published previously in the journal. The Editors reserve the right to suggest submission to another journal for those papers which they feel would be more appropriate for consideration by that journal.
Original research papers of high quality and novelty on aspects of control, host response, molecular biology, pathogenesis, prevention, and treatment of microbial diseases of animals are published. Papers dealing primarily with immunology, epidemiology, molecular biology and antiviral or microbial agents will only be considered if they demonstrate a clear impact on a disease. Papers focusing solely on diagnostic techniques (such as another PCR protocol or ELISA) will not be published - focus should be on a microorganism and not on a particular technique. Papers only reporting microbial sequences, transcriptomics data, or proteomics data will not be considered unless the results represent a substantial advance in knowledge.
Drug trial papers will be considered if they have general application or significance. Papers on the identification of microorganisms will also be considered, but detailed taxonomic studies do not fall within the scope of the journal. Case reports will not be published, unless they have general application or contain novel aspects. Papers of geographically limited interest, which repeat what had been established elsewhere will not be considered. The readership of the journal is global.