The chicken Tva cell surface protein, a member of the low-density lipoprotein receptor family, has been identified as an entry receptor for avian leukosis virus of classic subgroup A and newly emerging subgroup K. Because both viruses represent an important concern for the poultry industry, we introduced a frame-shifting deletion into the chicken tva locus with the aim of knocking-out Tva expression and creating a virus-resistant chicken line. The tva knock-out was prepared by CRISPR/Cas9 gene editing in chicken primordial germ cells and orthotopic transplantation of edited cells into the testes of sterilized recipient roosters. The resulting tva -/- chickens tested fully resistant to avian leukosis virus subgroups A and K, both in in vitro and in vivo assays, in contrast to their susceptible tva +/+ and tva +/- siblings. We also found a specific disorder of the cobalamin/vitamin B12 metabolism in the tva knock-out chickens, which is in accordance with the recently recognized physiological function of Tva as a receptor for cobalamin in complex with transcobalamin transporter. Last but not least, we bring a new example of the de novo resistance created by CRISPR/Cas9 editing of pathogen dependence genes in farm animals and, furthermore, a new example of gene editing in chicken.

• Keywords
• avian leukosis virus subgroups A/K, gene editing in chicken, tva, vitamin B12/cobalamin,
• MeSH
• Gene Editing MeSH
• Gene Knockout Techniques MeSH
• Chickens virology   MeSH
• Chick Embryo MeSH
• Methylmalonic Acid blood   MeSH
• Frameshift Mutation MeSH
• Avian Proteins genetics   physiology   MeSH
• Receptors, Virus genetics   physiology   MeSH
• Avian Leukosis Virus classification   physiology   MeSH
• Vitamin B 12 metabolism   MeSH
• Animals MeSH
• Check Tag
• Chick Embryo MeSH
• Male MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Methylmalonic Acid MeSH
• Avian Proteins MeSH
• Tva receptor MeSH Browser
• Receptors, Virus MeSH
• Vitamin B 12 MeSH

The ongoing progress in primordial germ cell derivation and cultivation is opening new ways in reproductive biotechnology. This study tested whether functional sperm cells can be matured from genetically manipulated primordial germ cells after transplantation in adult testes and used to restore fertility. We show that spermatogenesis can be restored after mCherry-expressing or GFP-expressing primordial germ cells are transplantated into the testes of sterilized G0 roosters and that mCherry-positive or GFP-positive non-chimeric transgenic G1 offspring can be efficiently produced. Compared with the existing approaches to primordial germ cell replacement, this new technique eliminates the germ line chimerism of G0 roosters and is, therefore, faster, more efficient and requires fewer animals. Furthermore, this is the only animal model, where the fate of primordial germ cells in infertile recipients can be studied.

• MeSH
• Phenotype MeSH
• Fertility * MeSH
• Chickens genetics   physiology   MeSH
• Spermatogenesis genetics   MeSH
• Spermatozoa cytology   MeSH
• Gene Transfer Techniques * MeSH
• Testis cytology   physiology   MeSH
• Transduction, Genetic MeSH
• Cell Transplantation * MeSH
• Animals MeSH
• Check Tag
• Male MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH