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Fruiting bodies of asco- and basidiomycetes are complex three-dimensional structures that protect and disperse the sexual spores. Their differentiation requires the concerted action of many genes, therefore "omics" techniques to analyze fungal genomes and gene expression at a genome-wide level provide excellent means to gain insights into this differentiation process. This review summarizes some recent examples of the use of “omics” techniques to study fruiting body morphogenesis. These include genome-centered analyses, and studies to analyze the regulation of gene expression including the analysis of RNA editing as a novel layer in the regulation of gene expression during fruiting body development in ascomycetes.

Myxobacteria are social bacteria, that can glide in two dimensions and form counter-propagating, interacting waves. Here, we present a novel age-structured, continuous macroscopic model for the movement of myxobacteria. The derivation is based on microscopic interaction rules that can be formulated as a particle-based model and set within the Self-Organized Hydrodynamics (SOH) framework. The strength of this combined approach is that microscopic knowledge or data can be incorporated easily into the particle model, whilst the continuous model allows for easy numerical analysis of the different effects. However, we found that the derived macroscopic model lacks a diffusion term in the density equations, which is necessary to control the number of waves, indicating that a higher order approximation during the derivation is crucial. Upon ad hoc addition of the diffusion term, we found very good agreement between the age-structured model and the biology. In particular, we analyzed the influence of a refractory (insensitivity) period following a reversal of movement. Our analysis reveals that the refractory period is not necessary for wave formation, but essential to wave synchronization, indicating separate molecular mechanisms.

Capillary electrophoresis equipped with Laser-induced fluorescence (CE-LIF), combining with micro-culture technique was employed to determine extracellular amino acids in single myxobacterial fruiting body morphogenesis. The result showed that in the early aggregation stage, there was a remarkable increase of extracellular amino acids, which was produced by developmentally induced autolysis. The amino acids were then consumed by the vegetative cells in aggregation stage. In the following developmental events, the extracellular amino acids were kept at low level, which indicated that in the stages of fruiting body formation and myxospore development, there was no further cell autolysis. Using this novel method may provide detailed insight into the mechanisms of the developmental phenomena.

The myxobacteria are the epitome of prokaryotic multicellular complexity. In particular, efforts have focused on understanding the nature, function, and regulation of the signals that play a role in the characteristic social behavior of the myxobacteria. The process of aggregation is correlated with a massive lysis of the population. The fruiting body is the culmination of myxobacterial development. The author presumes that it represents the housing for the resting cells, called myxospores. The peculiar ecological habitat of each myxobacterium may dictate a particular myxospore-packaging requirement and thus a characteristic fruiting body morphology. The myxospores are the resting cells of the myxobacteria and are found within the fruiting body. One of the functions of the fruiting body may be rationalized in a similar fashion. The fruiting body may be viewed as a device whereby the cells, prior to entering the resting stage, aggregate and are concentrated at a high cell density. Understanding fruiting body morphogenesis is among the most difficult and challenging aspects of myxobacterial biology. Most of the studies directed toward the properties of fruiting body myxospores have focused on various cell surface proteins. Bacteria have traditionally been thought of as exemplifying the concept of the unicellular organism.

Induced by starvation, the development of fruiting bodies by Myxococcus xanthus on glass and plastic surfaces under a layer of liquid was followed microscopically. Calcium ions and a neutral pH were required for development of a Myxococcus strain that grew dispersed in liquid culture. Initially asymmetric aggregates later became round, and sporulation followed aggregation.