An evolutionarily conserved mechanism underlies interspecies cell-cell signalling in fungi

Area of Science:

• Mycology
• Cell Biology
• Fungal Development

Background:

• Filamentous fungi, such as Neurospora crassa, grow as hyphae that form a mycelial network.
• Hyphal growth involves elongation, branching, and tip fusion, contributing to mycelial morphology.
• Tip fusion is a critical process for maintaining cytoplasmic continuity within the mycelium.

Purpose of the Study:

• To investigate the molecular mechanisms underlying hyphal tip fusion in Neurospora crassa.
• To understand the communication dynamics between interacting hyphal tips during fusion.

Main Methods:

• Utilized fluorescently tagged Neurospora proteins (MAK-2 and SO) to visualize hyphal interactions.
• Observed genetically identical conidia (germlings) during the germination and fusion process.
• Analyzed the spatial and temporal dynamics of molecular signaling between hyphal tips.

Main Results:

• Discovered that hyphal tips within 15 μm of each other engage in oscillatory molecular signaling.
• Demonstrated a back-and-forth exchange of signals, with tips alternating between sending and receiving.
• Identified this oscillatory signaling as a key component of the tip fusion process.

Conclusions:

• Hyphal tip fusion in Neurospora crassa is regulated by a dynamic, oscillatory molecular communication system.
• This signaling mechanism ensures coordinated interaction between germinating hyphae for successful fusion.
• The findings provide novel insights into the intricate processes governing fungal development and morphology.