CRISPR/Cas9-Mediated Genome Editing via Homologous Recombination in a Centric Diatom .

, the most abundant genus of marine planktonic diatoms, can be used in mariculture. An effective genetic transformation system with a short transformation period was established in by electroporation in our previous study. In this study, a sequence-specific clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 vector applicable for was constructed, and the expressions of sgRNA, resistance gene, and gene were driven by the endogenous promoters , and , respectively, in the vector. () and () genes were edited in , and the knockout and / double-knockout lines displayed the strict auxotrophic phenotype. In addition, the DNA double-strand break was repaired by homologous recombination when a donor DNA was introduced. CRISPR/Cas9 technology was successfully applied to with an editing efficiency of up to 86%, providing a molecular tool for the study of basic biology in and its synthetic biology applications.