Virus infection and persistence of foreign DNA in the marine brown alga Feldmannia simplex (Ectocarpales, Phaeophyceae)

Abstract

Endogenous viruses are found in the two filamentous marine brown algae Ectocarpus siliculosus (Dillwyn) Lyngbye and Feldmannia simplex (Crouan) Hamel. We have performed experiments showing that the Ectocarpus siliculosus virus (EsV-1) is able to infect zoospores of Feldmannia. EsV-1 did not multiply in Feldmannia, but its presence caused malformations of the host. The symptoms soon disappeared and the plants recovered to normal habit and fertility. After two years of culture we subjected DNA of EsV-1-infected Feldmannia to PCR amplification with oligomer primers specific for a gene that codes for a coat protein of the Ectocarpus virus. Our results indicate that Ectocarpus virus DNA can persist in Feldmannia, and that phenotypically normal Feldmannia simplex can harbour latent Ectocarpus virus DNA.