Establishment of conidial fusion in the asexual fungus Verticillium dahliae as a useful system for the study of non-sexual genetic interactions

Abstract Cell-to-cell fusion is a fundamental biological process across the tree of life. In filamentous fungi, somatic (or anastomosis) required for normal development their syncytial hyphal networks, and it can initiate non-sexual genetic exchange processes, such as horizontal transfer parasexual cycle. Although these could be important drivers evolution asexual this remains largely unexplored possibility due to lack suitable resources study in puzzling organisms. We thus aimed at characterization cell fungus Verticillium dahliae via Conidial Anastomosis Tubes (CATs), which useful analysis parasexuality. optimized appropriate procedures highly reproducible quantification live-cell imaging, were used characterize physiology biology, start elucidating underlying machinery. Formation CATs was shown depend on growth conditions require functional Fus3 Slt2 MAP kinases, well NADPH oxidase NoxA, whereas GPCR Ste2 mating-type protein MAT1-2-1 dispensable. show that nuclei other organelles migrate through CATs, often leads formation transient dikaryons. Their have possible windows opportunity interaction before degradation one by presumably homeostatic mechanism. establish here CAT-mediated V. an experimentally convenient system cytological fungal interactions. expect will facilitate dissection sexual alternatives fungi.