title: Analysis of natural recombination in porcine endogenous retrovirus envelope genes.
abstract: Human tropic Porcine Endogenous Retroviruses (PERVs) are the major concern in zoonosis for xenotransplantation because PERVs cannot be eliminated by specific pathogen-free breeding. Recently, a PERV A/C recombinant with PERV-C bearing PERV-A gp70 showed a higher infectivity (approximately 500-fold) to human cells than PERV-A. Additionally, the chance of recombination between PERVs and HERVs is frequently stated as another risk of xenografting. Overcoming zoonotic barriers in xenotransplantation is more complicated by recombination. To achieve successful xenotransplantation, studies on the recombination in PERVs are important. Here, we cloned and sequenced proviral PERV env sequences from pig gDNAs to analyze natural recombination. The envelope is the most important element in retroviruses as a pivotal determinant of host tropisms. As a result, a total of 164 PERV envelope genes were cloned from pigs (four conventional pigs and two miniature pigs). Distribution analysis and recombination analysis of PERVs were performed. Among them, five A/B recombinant clones were identified. Based on our analysis, we determined the minimum natural recombination frequency among PERVs to be 3%. Although a functional recombinant envelope clone was not found, our data evidently show that the recombination event among PERVs may occur naturally in pigs with a rather high possibility.
authors.affiliation: Department of Animal Biotechnology, College of Animal Bioscience and Technology, Konkuk University, Seoul 143-701, Korea.
authors.forename: Donghee
authors.initials: D
authors.lastname: Lee
authors.forename: Jungeun
authors.initials: J
authors.lastname: Lee
authors.forename: Nuri
authors.initials: N
authors.lastname: Park
authors.forename: Yu-Kyung
authors.initials: YK
authors.lastname: Oh
authors.forename: Moosik
authors.initials: M
authors.lastname: Kwon
authors.forename: Young Bong
authors.initials: YB
authors.lastname: Kim
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D003001:Cloning, Molecular; D020077:Endogenous Retroviruses / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D006031:Glycosylation; D006801:Humans; D007723:Korea; D008969:Molecular Sequence Data; D010802:Phylogeny; D011995:Recombination, Genetic; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013552:Swine / Q000821:virology*; D014759:Viral Envelope Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D014759:Viral Envelope Proteins