Localization and transcription patterns of LsVasa, a molecular marker of germ cells in Lepeophtheirus salmonis (KrOyer)

Lepeophtheirus salmonis (salmon louse) is an ectoparasitic copepod. The salmon louse is an economically important pathogen in aquaculture and poses a serious threat to wild populations of salmonids. Whereas the ecology and biology of the salmon louse has been described to some extent, information on the molecular level is limited. A key step in the struggle to limit the number of salmon lice in farmed fish includes methods to limit reproduction in adult female lice. Here we describe a salmon louse homologue of the germ cell marker Vasa named Lepeophtheirus salmonis Vasa (LsVasa). Vasa, an RNA helicase, is a highly conserved gene found in germ cells in many organisms. The structure and sequence of LsVasa is described and localization and quantification of LsVasa transcripts is presented.