Evolutionary innovations through gain and loss of genes in the ectomycorrhizal Boletales

SUMMARYIn this study, we aim to identify genomic traits of the transitions to the ectomycorrhizal ecology within the Boletales, one of the most diverse lineages of symbiotrophic fungi.We sequenced the genomes and compared the gene repertoires of symbiotrophic Boletales species to their saprotrophic brown-rot relatives. We also reconstructed gene duplication/loss histories along a time-calibrated phylogeny.We showed that the rate of gene duplication is constant along the backbone of Boletales phylogeny with large loss events in lineages leading to several families. The rate of gene family expansion sharply increased in the late Miocene and mostly took place in Boletaceae.Most of the ectomycorrhizal Boletales are characterized by a large genome size due to transposable element (TE) expansions and a reduction in the diversity of plant cell wall degrading enzymes (PCWDEs) compared to their brown-rot relatives. However, several species in the Boletaceae, Paxillaceae and Boletinellaceae have kept a substantial set of endoglucanases and LPMOs acting on cellulose/hemicellulose and fungal polysaccharides suggesting that they may partly decompose organic matter by a combined activity of oxidative and hydrolytic enzymes.The present study provides novel insights on our understanding of the mechanisms that influence the evolutionary diversification of boletes and symbiosis evolution.

Symbiosis Evolution of Science Communication Ecosystem Based on Social Media: A Lotka–Volterra Model-Based Simulation

Social media has become an important way for science communication. Some scholars have examined how to help scientists engage with social media from operational training, policy guidance, and social media services improving. The main contribution of this study is to construct a symbiosis evolution model of science communication ecosystem (SCE) between scientists and social media platforms based on the symbiosis theory and the Lotka–Volterra model to discuss the evolution of their symbiotic patterns and population size under different symbiosis coefficients. The results indicate that (1) the size of the symbiosis coefficients determines the equilibrium outcome of the symbiosis evolution of scientists and social media platforms; (2) scientists and social media platforms can promote each other’s population size under the mutualism pattern, which can achieve sustainable science communication; (3) “1 + 1 > 2” effect can only be achieved under the symmetric mutualism pattern and the growth of scientists and social media platforms is more stable and sufficient than that of other patterns. The findings will provide additional perspectives for promoting the sustainable development of science communication based on social media.

Genomes of Wolbachia endosymbionts from the human filarial parasites Mansonella perstans and Mansonella ozzardi

Mansonella ozzardi and Mansonella perstans, filarial parasites infecting millions of people worldwide, harbor their unique obligate endosymbionts, the alpha-proteobacteria WolbachiawMoz and wMpe, respectively. Currently, little is known about these Wolbachia and no genome sequences are available. In the current study, high quality draft genomes of wMoz and wMpe were assembled from complex clinical samples using a metagenome assembly and binning approach. These represent the first genomes from supergroup F Wolbachia originating from human parasites and share features characteristic of filarial as well arthropod Wolbachia, consistent with their position in supergroup F. Metagenomic data analysis was also used to estimate Wolbachia titers, which revealed wide variation in levels across different clinical isolates, addressing the contradicting reports on presence or absence of Wolbachia in M. perstans. These findings may have implications for the use antibiotics to treat mansonellosis. The wMoz and wMpe genome sequences provide a valuable resource for further studies on symbiosis, evolution and drug discovery.

Stakeholder Symbiosis in the Context of Corporate Social Responsibility

With the rise of corporate social responsibility (CSR) and the great changes of the organization scale of the modern enterprise, it is difficult to maintain an ideal development only by maximizing the equity of shareholders. The co-governance of stakeholders can meet the interests of all stakeholders, which is the embodiment of corporate social responsibility in corporate governance. The creation and sharing of enterprise values are the foundation of the coexistence of stakeholders. A rational allocation of the limited enterprise values among stakeholders plays a crucial role in balancing their relationship and realizing the sustainable development of the enterprise. Based on the application of corporate social responsibility in stakeholder governance, this paper constructs a stakeholder symbiosis evolution model with the help of symbiosis theory. By solving the differential equation, the symbiotic evolution path of stakeholders is analyzed. The dynamic mechanism of stakeholder Symbiosis evolution is analyzed by using the system analysis method and evolution theory. The dynamic mechanism of the population evolution of stakeholders is represented in an original graphical manner to describe the symbiotic evolution process of stakeholders. Lastly, we use the numerical simulation method to simulate different symbiosis models which are reflected by different symbiosis coefficients. It is concluded that the symmetric mutual benefit symbiosis model is the most effective model to reflect corporate social responsibility.

The partitioning of symbionts effects on host resource acquisition and developmental plasticity

Many symbionts provide nutrients to their host and/or affect its phenotypic plasticity. Such symbiont effects on host resource acquisition and allocation are often simultaneous and difficult to disentangle. Here we partitioned symbiont effects on host resource acquisition and allocation using a new framework based on the analysis of a well-established trade-off between host fitness components. This framework was used to analyze the effect of symbiotic yeast on the larval development of Drosophila larvae in field-realistic conditions. The screening of eighteen yeast fresh isolates showed they had similar effects on the resource acquisition in Drosophila melanogaster, D. simulans and D. suzukii but species-specific effects on resource allocation between either larval development speed or adult size. These differences shed light on the ecology of Drosophila flies and illustrate why distinguishing between these qualitatively different effects of microorganisms on hosts is essential to understand and predict symbiosis evolution.

Arsenophonus and Sodalis Symbionts in Louse Flies: an Analogy to the Wigglesworthia and Sodalis System in Tsetse Flies

ABSTRACTSymbiosis between insects and bacteria result in a variety of arrangements, genomic modifications, and metabolic interconnections. Here, we present genomic, phylogenetic, and morphological characteristics of a symbiotic system associated withMelophagus ovinus, a member of the blood-feeding family Hippoboscidae. The system comprises four unrelated bacteria representing different stages in symbiosis evolution, from typical obligate mutualists inhabiting bacteriomes to freely associated commensals and parasites. Interestingly, the whole system provides a remarkable analogy to the association betweenGlossinaand its symbiotic bacteria. In both, the symbiotic systems are composed of an obligate symbiont and two facultative intracellular associates,SodalisandWolbachia. In addition, extracellularBartonellaresides in the gut ofMelophagus. However, the phylogenetic origins of the two obligate mutualist symbionts differ. InGlossina, the mutualisticWigglesworthiaappears to be a relatively isolated symbiotic lineage, whereas inMelophagus, the obligate symbiont originated within the widely distributedArsenophonuscluster. Although phylogenetically distant, the two obligate symbionts display several remarkably similar traits (e.g., transmission via the host's “milk glands” or similar pattern of genome reduction). To obtain better insight into the biology and possible role of theM. ovinusobligate symbiont, “CandidatusArsenophonus melophagi,” we performed several comparisons of its gene content based on assignments of the Cluster of Orthologous Genes (COG). Using this criterion, we show that within a set of 44 primary and secondary symbionts, “Ca. Arsenophonus melophagi” is most similar toWigglesworthia. On the other hand, these two bacteria also display interesting differences, such as absence of flagellar genes inArsenophonusand their presence inWigglesworthia. This finding implies that a flagellum is not essential for bacterial transmission via milk glands.

The oxidative environment: a mediator of interspecies communication that drives symbiosis evolution

Symbiotic interactions are ubiquitous in nature and play a major role in driving the evolution of life. Interactions between partners are often mediated by shared signalling pathways, which strongly influence both partners' biology and the evolution of the association in various environments. As an example of ‘common language’, the regulation of the oxidative environment plays an important role in driving the evolution of symbiotic associations. Such processes have been occurring for billions of years, including the increase in Earth's atmospheric oxygen and the subsequent evolution of mitochondria. The effect of reactive oxygen species and reactive nitrogen species (RONS) has been characterized functionally, but the molecular dialogue between partners has not been integrated within a broader evolutionary context yet. Given the pleiotropic role of RONS in cell–cell communication, development and immunity, but also their associated physiological costs, we discuss here how their regulation can influence the establishment, the maintenance and the breakdown of various symbiotic associations. By synthesizing recent developments in redox biology, we aim to provide an interdisciplinary understanding of the influence of such mediators of interspecies communication on the evolution and stability of symbioses, which in turn can shape ecosystems and play a role in health and disease.

Symbiosis Equilibrium Stable Range Analysis of Multi-Owner Cascade Hydro Plants

It is a huge dynamic dimensional optimization question for the optimal operation of multi-owner cascade hydro plants constrained by water use competition and market strategies cooperation. The symmetry mutualism behavior patterns between multi-owner hydro plants are described accurately based on symbiosis theory. Then the mathematical model of the cascade symbiosis alliance in symmetry mutualisms pattern is built and the equilibrium solutions are presented. We discuss the symbiosis equilibrium stability range of multi-owner cascade hydro plants. Finally, simulation results obtained demonstrate that the proposed stable range is proficient and the symbiosis evolution law is revealed.