Aggregation during fruiting body formation in Myxococcus xanthus is driven by reducing cell movement

Area of Science:

• Microbiology
• Developmental Biology
• Computational Biology

Background:

• Myxococcus xanthus undergoes a complex developmental cycle when starved, forming multicellular fruiting bodies.
• The early stages of fruiting body formation involve cell aggregation and differentiation into spores.

Purpose of the Study:

• To investigate cell behaviors, including velocity, orientation, and reversal rates, during the initial phases of Myxococcus xanthus fruiting body development.
• To elucidate the mechanisms driving cell accumulation into aggregates and the role of the Frz system in morphogenesis.

Main Methods:

• Direct observation of cell velocities, orientations, and reversal frequencies during aggregation.
• Development and utilization of a continuous agent-based computational model to simulate early fruiting body formation.
• Experimental manipulation of the Frz system in Myxococcus xanthus mutants to assess effects on fruiting body shape.

Main Results:

• Cell velocities significantly decrease during aggregation, leading to cell accumulation.
• Cells initially orient in parallel within aggregates, later adopting circumferential orientations.
• Computational modeling successfully replicated observed aggregation dynamics and early fruiting body development.
• Changes in reversal frequency, modulated by the Frz system, impact the morphology of early fruiting bodies.

Conclusions:

• Slowing of cell velocity is the primary driver for cell aggregation in Myxococcus xanthus development.
• Agent-based modeling provides a robust framework for understanding the biophysical processes of fruiting body formation.
• The Frz signaling network plays a crucial role in coordinating cell behavior and shaping the developing fruiting body.