7 The Art of Networking: Vegetative Hyphal Fusion in Filamentous Ascomycete Fungi
Hyphal fusion is a common feature of the growth and development of filamentous ascomycete fungi. It occurs at various developmental stages, most prominently during colony establishment by germinating spores and during the formation of cross connections within mature mycelial colonies. Recent years have seen great advances in understanding the biological roles and the molecular mechanisms of this fascinating biological process. It has become apparent that hyphal fusion promotes the formation of the mycelial network, thereby increasing fitness and competitiveness of the fungal colony. On the molecular level, an intricate signaling network controlling communication, attraction, and merger of fusing hyphae has been identified. This network comprises many well-conserved factors, including MAP kinases, reactive oxygen-generating systems, Ca2+-binding regulators, the STRIPAK complex, and cell polarity factors, which are partially adopted in novel and surprising ways. Studying the role and function of hyphal fusion therefore holds much potential to further our understanding not only of fungal growth and development but also of general eukaryotic cell biology.
KeywordsFusion Partner Fusion Pore Hyphal Fusion Cell Wall Integrity Pathway Membrane Recruitment
Work in our group is supported by funding from the German Research Foundation (FL706-2) and the European Union (PITN-GA-2013-607963) to A.F.
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