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Boggiatto, P.

Publications and source records attributed to Boggiatto, P..

5 recordsLinked to original sources

Recurrent Duplication of the REST-NOA1 Locus Reveals a Hotspot of Regulatory Evolution Across Even-Toed Ungulates

Gene duplication is a major source of evolutionary novelty, yet recurrent duplication of the same genomic locus across independent lineages remains understudied. Using a chromosome-scale assembly and de novo annotation of the North American bison (Bison bison), we investigated the mechanisms underlying immune-system diversification in ungulates. Comparative genomics of bison, cattle, elk, and 13 mammalian species identified a large segmental duplication encompassing the regulatory genes REST and NOA1. Although similar duplications were present in 14/16 species examined, phylogenetic analyses revealed that duplicated genes cluster within species rather than across taxa, indicating repeated independent origins rather inheritance from a common ancestor. To characterize the evolutionary consequences of this duplication, we integrated transcriptomics from six tissues with weighted gene co-expression and comparative protein clustering. We identified extensive structural divergence among duplicated copies of REST and NOA1, including domain losses, truncations, and expression partitioning across tissues, consistent with functional divergence following duplication. Comparative analyses revealed substantial remodeling of immune-related genes in bison, including BOLA class I molecules, T-cell receptor genes, leukocyte immunoglobulin-like receptors, and regulators of immune signaling. These modifications included domain rearrangements, novel sequence insertions, and lineage-specific duplications associated with immune-related expression networks. Together, these findings identify the REST-NOA1 locus as a recurrent hotspot of segmental duplication in ungulates and demonstrate how repeated duplication, structural divergence, and regulatory partitioning contribute to genome evolution. These results suggest that immune system diversification in bison and related species has been shaped not only by sequence evolution but also by recurrent remodeling of regulatory pathways and antigen-recognition pathways.

bioinformatics↗

Evaluation of an H5 influenza virus mRNA-lipid nanoparticle (LNP) vaccine in lactating dairy cows

Highly pathogenic avian influenza (HPAI) clade 2.3.4.4b H5N1 virus has recently emerged in dairy cattle in the United States. The virus replicates primarily in the mammary gland of infected cattle, leading to dramatic reductions in milk production. It is thought that the virus transmits from animal to animal through viral shedding in milk, and therefore, vaccines that decrease the amount of virus in milk can potentially limit the current outbreak and reduce the risk of H5N1 spillover into humans. Here, we assess the immunogenicity and efficacy of a clade 2.3.4.4b H5 mRNA-LNP vaccine in lactating dairy cows. We found that the H5 mRNA-LNP vaccine elicited robust antibody responses in sera and milk and significantly reduced viral replication and disease caused by clade 2.3.4.4b H5N1 intramammary infection.

microbiology↗

H5 influenza virus mRNA-lipid nanoparticle (LNP) vaccination elicits adaptive immune responses in Holstein calves

Highly pathogenic avian influenza (HPAI) clade 2.3.4.4b H5N1 is circulating widely in lactating cows in the United States. Due to the critical need for intervention strategies for this outbreak, we evaluated antibody and cellular immune responses of a clade 2.3.4.4b H5 mRNA-LNP vaccine in calves. We found that the H5 mRNA-LNP vaccine induced a robust antibody and CD8+ T cellular-mediated immune response and conferred protection against clade 2.3.4.4b H5N1 infection.

microbiology↗

Experimental reproduction of viral replication and disease in dairy calves and lactating cows inoculated with highly pathogenic avian influenza H5N1 clade 2.3.4.4b

Highly pathogenic avian influenza (HPAI) H5N1 of the hemagglutinin clade 2.3.4.4b was detected in the United States in late 2021 and continues to circulate in all four North American flyways to date. In addition to impacting poultry, these HPAI viruses caused mortality events in wild bird species and wild mammals. Transmission in multiple host species raises the concern for mammalian adaptation. On March 25, 2024, HPAI H5N1 clade 2.3.4.4b was confirmed in a dairy cow in Texas in response to a multi-state investigation into milk production losses. Over one hundred positive herds were rapidly identified in Texas and eleven other U.S. states. The case description included reduced feed intake and rumen motility in lactating cows, decreased milk production, and thick yellow milk. The diagnostic investigation revealed detections of viral RNA in milk and mammary tissue with alveolar epithelial degeneration and necrosis, and positive immunoreactivity of glandular epithelium by immunohistochemistry. A single transmission event, likely from avian species to dairy cattle, followed by limited local transmission preceded the onward lateral transmission of H5N1 clade 2.3.4.4b genotype B3.13. We sought to experimentally reproduce infection with genotype B3.13 in Holstein yearling heifers and lactating cows. The heifers were inoculated by an aerosol respiratory route and the cows by an intramammary route. Clinical disease was mild in the heifers, but infection was confirmed by virus detection, lesions, and seroconversion. Clinical disease in lactating cows included decreased rumen motility, changes to milk appearance, and production losses consistent with field reports of viral mastitis. Infection was confirmed by high levels of viral RNA detected in milk, virus isolation, lesions in mammary tissue, and seroconversion. This study provides the foundation to investigate additional routes of infection, transmission, and intervention strategies.

microbiology↗

A pseudomolecule assembly of the Rocky Mountain elk genome reveals putative immune system gene loss near chromosomal fissions

Rocky Mountain elk (Cervus canadensis) is a major reservoir for Brucella abortus in the Greater Yellowstone area, which has significant economic implications to the cattle industry. Vaccination attempts against intracellular bacterial diseases in elk populations have not been successful due to a negligible adaptive cellular immune response. A lack of genomic resources has impeded attempts to better understand why vaccination does not induce protective immunity. To overcome this limitation, PacBio, Illumina, and HiC sequencing with a total of 686-fold coverage was used to assemble the elk genome into 35 pseudomolecules. A robust gene annotation was generated resulting in 18,013 gene models and 33,422 mRNAs. The accuracy of the assembly was assessed using synteny to the red deer and cattle genomes identifying several chromosomal rearrangements, fusions and fissions. Because this genome assembly and annotation provide a foundation for genome-enabled exploration of Cervus species, we demonstrate its utility by exploring the conservation of immune system-related genes. We conclude by comparing cattle immune system-related genes to the elk genome, revealing nine putative gene losses in elk. Author SummaryBrucellosis, also known as contagious abortion, is a bacterial disease that commonly affects livestock and remains prevalent in Rocky Mountain elk (Cervus canadensis). Since the 1920s the USDA has led a program to eradicate Brucellosis from cattle, yet wild Rocky Mountain elk continue to be a source of transmission. Attempts to vaccinate wild elk herds have been unsuccessful, due to a poor and short-lived immune response. To investigate the genetic basis for this inherent difference, we created the first genome and annotation for the Rocky Mountain elk. This genome assembly is of the highest quality and contains single linear sequences for all 35 chromosomes. In order to generate gene models, an array of RNA-Seq data and proteins from many different organ tissues and cells were used in gene prediction software. Specifically, we compare cattle immune system genes with the Rocky Mountain elk, revealing the putative loss of nine immune-system related genes in elk.

genomics↗