Establishment of TurboID proximity proteomics in the filamentous fungus Sordaria macrospora

Biotin identification (BioID) is a proximity-dependent labeling technique to study protein-protein co-localization in vivo. Although BioID has been applied in animal cells, plants and yeast, the method remained to be established in filamentous fungi. In this study, we established BioID for the filamentous fungus Sordaria macrospora using the well-characterized striatin interacting phosphatase and kinase (STRIPAK) complex as a proof of principle. In detail, the STRIPAK complex interactor 1 (SCI1) was fused to a codon-optimized TurboID biotin ligase. This SCI1-TurboID fusion protein complemented the Δsci1 deletion strain phenotype. The identification of the already known SmSTRIPAK components PRO11, SmMOB3, SmPP2Ac1 and PRO22 in a BioID experiment with SCI1-TurboID demonstrated its successful application in S. macrospora. The technique will provide a powerful proteomics tool for fungal biologists.