Recombination, distribution and evolution of endogenous retroelements in birds.

• Main Author: Krishnan, Mallika
• Other Authors: Mindell, David P.
• Format: Thesis
• Language: English
• Published: 2003
• Subjects: Accipiter Cooperii; Avian Sarcoma And Leukosis Virus; Birds; Bonasa Umbellus; Colinus Virginianus; Dendragapus Falcipennis; Distribution; Endogenous; Evolution; Falco Peregrinus; Melopsittacus Undulata; Recombination; Retroelements; Falco peregrinus; peregrine falcon
• Online Access: https://hdl.handle.net/2027.42/123420; http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqm&rft_dat=xri:pqdiss:3079476

Endogenous retroviruses have been observed in almost all vertebrates. Most work on avian retroviruses has focused on alpharetroviruses in domesticated galliform species. Very little is known about avian retroviral diversity, evolution and distribution outside of domesticated birds. To understand retroviral origins, life histories and mechanisms of transmission, a greater knowledge of the diversity and distribution of retroviruses in non-domesticated species is required. Comparisons of well-corroborated retroviral and host species phylogeny for phylogenetic congruence or incongruence can aid in estimating the relative frequency of vertical transmission compared to horizontal transmission of retroviruses among host species. Six novel replication defective retroelements were isolated from a Colinus virginianus (Northern Bobwhite quail) and a Dendragapus falcipennis (Siberian Grouse) individual. Two of the retroelements have regions with similarity to Murine Endogenous Retrovirus-L like polymerase ( pol ). Distribution of pol in avian hosts indicates a history of horizontal transmission. The pol element was observed in three non-galliform species, Falco peregrinus (Peregrine falcon), Accipiter cooperii (Cooper's hawk), and Melopsittacus undulata (Budgerigar). Reverse transcriptase (RT) elements were observed in association with TERV-like retroelements in one galliform and four non-galliform species. The RT is monophyletic within a TERV group of viruses. ASLV gag was also observed in the Peregrine Falcon. In a study of distribution and evolution of alpharetroviruses, avian sarcoma and leukosis virus (ASLV) gag genes were found in 26 species of galliform birds from various geographic regions. 19 of the 26 host species were not previously known to contain ASLVs. Vertical transmission of ASLVs is inferred from congruent ASLV and host phylogenies for Perdix, Gallus, and two Lagopus species. Horizontal transmission of ASLVs among some members of the Tetraoninae sub-family (grouse and ptarmigan) is supported by the ASLV ...