Here we present a collection of methods established for genetic manipulation of Paradiplonema papillatum (also referred to as Diplonema papillatum), so far the only diplonemid species that is genetically tractable and can therefore serve as a model organism, enabling functional studies of this very abundant and species-rich group of marine protists. We describe a complete transformation protocol which includes: (1) the Alamar blue assay, a method that serves to identify antibiotics, to which P. papillatum is sensitive and can be used for transformant selection; (2) the design and preparation of DNA constructs for functional genomics; and (3) two protocols for electroporation and transformant screening. We conclude with an immunoprecipitation protocol optimized for pulling down target-tagged proteins along with their interaction partners, allowing the characterization of protein complexes.

Centre for Cell Biology Institute of Cell Biology School of Biological Sciences University of Edinburgh Edinburgh UK

Department of Biochemistry and Robert Cedergren Centre for Bioinformatics and Genomics Université de Montréal Montréal QC Canada

Faculty of Science University of South Bohemia České Budějovice Czech Republic

Institute of Parasitology Biology Centre Czech Academy of Sciences České Budějovice Czech Republic

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