Cell response of Mayamaea pseudoterrestris to heavy metals

A freshwater pennate diatom, Mayamaea pseudoterrestris is proposed as an alternative strain recommended for ecotoxicological test (OECD, TG201). However, the genomic backgrounds for the rapid cell response of diatoms to exposure of heavy metal is little known. M. pseudoterrestris possesses the relatively small genome and it was considered that it showed simple cell responses to heavy metal. In this study, we sequenced the genome of M. pseudoterrestris, and revealed the rapid cell responses of M. pseudoterrestris by using RNA-seq analysis and various physiological experiments. The M. pseudoterrestris genome encoded the smallest gene repertories in freshwater diatoms and they are highly similar to those of a model marine diatom, Phaeodactylum tricornutum.