title: Degenerate tetraploidy was established before bdelloid rotifer families diverged.
abstract: Rotifers of Class Bdelloidea are abundant freshwater invertebrates known for their remarkable ability to survive desiccation and their lack of males and meiosis. Sequencing and annotation of approximately 50-kb regions containing the four hsp82 heat shock genes of the bdelloid Philodina roseola, each located on a separate chromosome, have suggested that its genome is that of a degenerate tetraploid. In order to determine whether a similar structure exists in a bdelloid distantly related to P. roseola and if degenerate tetraploidy was established before the two species separated, we sequenced regions containing the hsp82 genes of a bdelloid belonging to a different family, Adineta vaga, and the histone gene clusters of P. roseola and A. vaga. Our findings are entirely consistent with degenerate tetraploidy and show that it was established before the two bdelloid families diverged and therefore probably before the bdelloid radiation.
authors.affiliation: Department of Molecular and Cellular Biology, Harvard University, USA.
authors.forename: Jae H
authors.initials: JH
authors.lastname: Hur
authors.forename: Karine
authors.initials: K
authors.lastname: Van Doninck
authors.forename: Morgan L
authors.initials: ML
authors.lastname: Mandigo
authors.forename: Matthew
authors.initials: M
authors.lastname: Meselson
mesh_terms: D000818:Animals; D005075:Biological Evolution; D006360:Heat-Shock Proteins / Q000235:genetics; D015801:Helminth Proteins / Q000235:genetics; D006657:Histones / Q000235:genetics; D005810:Multigene Family; D011123:Polyploidy; D012403:Rotifera / Q000235:genetics*
chemical_list: D006360:Heat-Shock Proteins; D015801:Helminth Proteins; D006657:Histones