Genomic characterization of novel dolphin papillomaviruses provides indications for recombination within the Papillomaviridae

Abstract

Phylogenetic analysis of novel dolphin (Tursiops truncatus) papillomavirus sequences, TtPV1, -2, and -3, indicates that the early and late protein coding regions of their genomes differ in evolutionary history. Sliding window bootscan analysis showed a significant a change in phylogenetic clustering, in which the grouped sequences of TtPV1 and -3 move from a cluster with the Phocoena spinipinnis PsPV1 in the early region to a cluster with TtPV2 in the late region. This provides indications for a possible recombination event near the end of E2/beginning of L2. A second possible recombination site could be located near the end of L1, in the upstream regulatory region. Selection analysis by using maximum likelihood models of codon substitutions ruled out the possibility of intense selective pressure, acting asymmetrically on the viral genomes, as an alternative explanation for the observed difference in evolutionary history between the early and late genomic regions of these cetacean papillomaviruses.

Emerging infectious diseases in cetaceans worldwide and the possible role of environmental stressors

“…As in other mammals (Howley & Lowy 2001) cetacean papillomaviruses appear to be speciesspecific (Van Bressem et al 2007a, Rector et al 2008). However, as recombination can occur between the Papillomaviridae leading to viable recombinants (Varsani et al 2006, Rector et al 2008, precaution is recommended when sampling genital warts in live cetaceans or fresh carcasses.…”

“…comm.). It was also diagnosed in captive T. truncatus in Europe and the USA (Bossart et al 2005, Rector et al 2008. Genital lesions macroscopically and microscopically consistent with PV-induced papillomas have also been seen in P. phocoena, short-beaked common dolphin Delphinus delphis and Stenella coeruleoalba from the British Isles (P. D. Jepson pers.…”

“…Other still uncharacterised PVs were detected in genital warts from Peruvian T. truncatus and Lagenorhynchus obscurus (Cassonnet et al 1998). Recombination of an ancestor of PsPV-1 and an ancestor of TtPV-2 may have generated the common ancestor of TtPV-1 and -3 (Rector et al 2008 the detection of PV sequences in 5 of the 7 genital warts examined indicated that PV infection is very frequent in this population. Though PVs are ubiquitous and commonly found on the skin and mucosae of the genital tract of humans and other animal species, clinical disease only develops in a small minority of them and it is believed that additional factors (immune status, genetic predispositions, nutritional status, environmental factors) are involved in the process of tumour development (Mougin et al 2001, Antonsson & Hansson 2002.…”

“…Three PVs (Tursiops truncatus [TtPV] papillomavirus type 1, 2 and 3) were associated with genital papillomatosis in dolphins from Europe and Atlantic USA (Rector et al 2008). Other still uncharacterised PVs were detected in genital warts from Peruvian T. truncatus and Lagenorhynchus obscurus (Cassonnet et al 1998).…”

Identification of a Novel Papillomavirus in a Northern Fulmar (Fulmarus glacialis) With Viral Production in Cartilage

“…coelebs and Fringilla montifringilla. 31 To date, there have been no reports of papillomaviruses or any neoplastic lesions in free-ranging seabirds despite the identification of papillomaviruses in numerous marine mammals, 5,35 including dolphins, 36,37 porpoises, 43 and sea turtles. 18 Regardless of host species, productive papillomavirus infection (formation of infectious particles) has been invariably tied to the terminal differentiation of epithelial cells.…”