title: Recurrent horizontal transfers of Chapaev transposons in diverse invertebrate and vertebrate animals.
abstract: Horizontal transfer (HT) of a transposable element (TE) into a new genome is regarded as an important force to drive genome variation and biological innovation. In addition, HT also plays an important role in the persistence of TEs in eukaryotic genomes. Here, we provide the first documented example for the repeated HT of three families of Chapaev transposons in a wide range of animal species, including mammals, reptiles, jawed fishes, lampreys, insects, and in an insect bracovirus. Multiple alignments of the Chapaev transposons identified in these species revealed extremely high levels of nucleotide sequence identity (79-99%), which are inconsistent with vertical evolution given the deep divergence time separating these host species. Rather, the discontinuous distribution amongst species and lack of purifying selection acting on these transposons strongly suggest that they were independently and horizontally transferred into these species lineages. The detection of Chapaev transposons in an insect bracovirus indicated that these viruses might act as a possible vector for the horizontal spread of Chapaev transposons. One of the Chapaev families was also shared by lampreys and some of their common hosts (such as sturgeon and paddlefish), which suggested that parasite-host interaction might facilitate HTs.
authors.affiliation: School of Life Sciences, Chongqing University, ChinaCollege of Pharmacy and Life Science, Jiujiang University, China.
authors.forename: Hua-Hao
authors.initials: HH
authors.lastname: Zhang
authors.affiliation: Department of Human Genetics, University of Utah School of Medicine.
authors.forename: Cédric
authors.initials: C
authors.lastname: Feschotte
authors.affiliation: School of Life Sciences, Chongqing University, China.
authors.forename: Min-Jin
authors.initials: MJ
authors.lastname: Han
authors.affiliation: School of Life Sciences, Chongqing University, China zezhang@cqu.edu.cn.
authors.forename: Ze
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D004251:DNA Transposable Elements; D018628:Gene Dosage; D022761:Gene Transfer, Horizontal; D008969:Molecular Sequence Data; D010802:Phylogeny; D016415:Sequence Alignment
chemical_list: D004251:DNA Transposable Elements
keywords: Chapaev; horizontal transfer; parasite–host interaction; viruses