Abstract

Yong Zhong Lu* and Jie Liu

As one of the most successful groups of microalgae in the contemporary ocean, diatoms are of ecological, biotechnological and evolutionary significance. Recent research has revealed for the first time the presence of functional silencing machinery in diatoms. Nevertheless, no microRNAs (miRNAs) participating in their gene regulation have been reported. Based on the principle of sequence conservation, previous known plant miRNAs were blasted against the expressed sequence tag databases of the marine diatoms Phaeodactylum tricornutum and Thalassiosira pseudonana and according to a series of filtering criteria, 6 conserved miRNAs were identified and 5 potential target genes of them were subsequently predicted. Alignmental and phylogenetic analyses showed that the miRNA precursor sequences were unexpectedly poorly conserved and distantly related to other family members. Above all, the findings from this study will contribute not only to further research of miRNAs features and regulatory mechanisms in diatoms, but also to their evolutionary research by virtue of new molecular tools.