Mazaedium evolution in the Ascomycota (Fungi) and the classification of mazaediate groups of formerly unclear relationship

Calicioid or mazaediate fungi constitute a heterogeneous assemblage of fungi sharing the presence of a mazaedium. These fungi were once treated as an order (Caliciales) of the Ascomycota but many are now known to be nested within the Arthoniomycetes, Eurotiomycetes, Lecanoromycetes and Leotiomycetes. In this study we employ multigene phylogenetic analyses of main mazaediate groups (based on nuclear 18S, 28S, 5.8S rDNA, mitochondrial 16S, and the protein coding RPB1 and Mcm7) of 116 taxa corresponding to most major groups of the inoperculate ascomycetes (“Leotiomyceta”) and a selection of Pezizomycetes, to trace the evolution of the mazaedium in the Pezizomycotina (the “Euascomycetes”). In particular, we studied the placement of three calicioid groups of uncertain position, Calycidiaceae, Coniocybaceae and Microcaliciaceae. Here, we show that the Calycidiaceae is closely related to the Sphaerophoraceae in the Lecanoromycetidae (Lecanoromycetes), as supported by overall morphology and the production of sphaerophorin. The Coniocybaceae constitute an early divergent line in the inoperculate ascomycetes and here we propose to recognize this group formally as the new class and order Coniocybomycetes, Coniocybales. The Microcaliciaceae is nested within the Ostropomycetidae (Lecanoromycetes). Both Coniocybaceae and Microcaliciaceae, although highly distinctive, lack morphological similarities to related main fungal groups. Ancestral state reconstruction suggests that the ancestor of all inoperculate ascomycetes and the ancestor of all main inoperculate ascomycete groups, with the exception of the Coniocybomycetes, was non‐mazediate, and thus confirms the large amount of parallel evolution and independent gains of the mazaedium in the history of the Ascomycota.     

Neural Mechanisms Underlying Breathing Complexity

Breathing is maintained and controlled by a network of automatic neurons in the brainstem that generate respiratory rhythm and receive regulatory inputs. Breathing complexity therefore arises from respiratory central pattern generators modulated by peripheral and supra-spinal inputs. Very little is known on the brainstem neural substrates underlying breathing complexity in humans. We used both experimental and theoretical approaches to decipher these mechanisms in healthy humans and patients with chronic obstructive pulmonary disease (COPD). COPD is the most frequent chronic lung disease in the general population mainly due to tobacco smoke. In patients, airflow obstruction associated with hyperinflation and respiratory muscles weakness are key factors contributing to load-capacity imbalance and hence increased respiratory drive. Unexpectedly, we found that the patients breathed with a higher level of complexity during inspiration and expiration than controls. Using functional magnetic resonance imaging (fMRI), we scanned the brain of the participants to analyze the activity of two small regions involved in respiratory rhythmogenesis, the rostral ventro-lateral (VL) medulla (pre-Bötzinger complex) and the caudal VL pons (parafacial group). fMRI revealed in controls higher activity of the VL medulla suggesting active inspiration, while in patients higher activity of the VL pons suggesting active expiration. COPD patients reactivate the parafacial to sustain ventilation. These findings may be involved in the onset of respiratory failure when the neural network becomes overwhelmed by respiratory overload We show that central neural activity correlates with airflow complexity in healthy subjects and COPD patients, at rest and during inspiratory loading. We finally used a theoretical approach of respiratory rhythmogenesis that reproduces the kernel activity of neurons involved in the automatic breathing. The model reveals how a chaotic activity in neurons can contribute to chaos in airflow and reproduces key experimental fMRI findings.     

Challenges in Providing Counselling to MSM in Highly Stigmatized Contexts: Results of a Qualitative Study from Kenya

The role of men who have sex with men (MSM) in the African HIV epidemic is gaining recognition yet capacity to address the HIV prevention needs of this group is limited. HIV testing and counselling is not only a critical entry point for biomedical HIV prevention interventions, such as pre-exposure prophylaxis, rectal microbicides and early treatment initiation, but is also an opportunity for focused risk reduction counselling that can support individuals living in difficult circumstances. For prevention efforts to succeed, however, MSM need to access services and they will only do so if these are non-judgmental, informative, focused on their needs, and of clear benefit. This study aimed to understand Kenyan providers'' attitudes towards and experiences with counselling MSM in a research clinic targeting this group for HIV prevention. We used in-depth interviews to explore values, attitudes and cognitive and social constructs of 13 counsellors and 3 clinicians providing services to MSM at this clinic. Service providers felt that despite their growing experience, more targeted training would have been helpful to improve their effectiveness in MSM-specific risk reduction counselling. They wanted greater familiarity with MSM in Kenya to better understand the root causes of MSM risk-taking (e.g., poverty, sex work, substance abuse, misconceptions about transmission, stigma, and sexual desire) and felt frustrated at the perceived intractability of some of their clients'' issues. In addition, they identified training needs on how to question men about specific risk behaviours, improved strategies for negotiating risk reduction with counselling clients, and improved support supervision from senior counsellors. This paper describes the themes arising from these interviews and makes practical recommendations on training and support supervision systems for nascent MSM HIV prevention programmes in Africa.     

Morphological and ultrastructural features in selected species of Licea (Myxomycetes)

Ultrastructural studies of selected species of Licea were made in order to elucidate relationships among species. Based on structural studies, species may be grouped as representing different stages of morphological complexity. The majority of species possess protoplasmodia and form sporangia. The two plasmodiocarpous species L. retiformis and L. variabilis possess more highly differentiated plasmodia and are an anomaly among Licea species. Processes along the margin of peridial lobes in several species of the genus are probably homologous with the capillitium in Listerella . The latter genus is morphologically and structurally very similar to species of the Licea pusilla group, but its plasmodium is still unknown. The sole species of Listerella agrees with Licea operculata in the structure of spore ornamentation, the processes consisting of densely packed granules of high electron density. This structure is quite different from that of L. pusilla and L. minima , where the processes have an internal structure of alternating layers different in electron transparency. Presence of spore-like bodies, different in size and ornamentation from normal spores, have been demonstrated in the border region between stalk and sporangium in L. operculata . This is a feature previously supposed to be restricted to Arcyria and related genera. Using X-ray analysis, calcium has been found in the peridium of several species of Licea . Since environmental factors may influence the presence or absence of calcium, caution should be taken in interpreting differences taxonomically. The similarity in elemental composition between the spores and sporangial lid in L. operculata is interesting, considering the fact that the sporangial lid of Trichia crateriformb has been demonstrated to be composed of spore-like structures.     

National‐scale analyses of habitat associations of Marsh Tits Poecile palustris and Blue Tits Cyanistes caeruleus: two species with opposing population trends in Britain

Capsule Marsh Tits were strongly associated with both the amount and species diversity of woodland understorey; Blue Tits were associated with large trees and deadwood.

Aims To gather quantitative information on the habitat requirements of Marsh Tits, in comparison with those of Blue Tits, across a large number of sites in England and Wales, and secondly to evaluate the range of habitat conditions likely to encourage the presence, and increase the abundance of, each species.

Methods Counts of birds were made at each of 181 woods across England and Wales, and habitat data were collected from the same locations in each woodland. Marsh Tit and Blue Tit presence and abundance were related to habitat characteristics, interspecific competition and deer impact.

Results Shrub cover and species diversity were important for the presence and abundance of Marsh Tits, across their geographical range in Britain. Blue Tits were associated with large trees and deadwood.

Conclusion Our results support the hypothesis that changes in woodland management, leading to canopy closure and a decline in the understorey available, could have had an impact on Marsh Tits, and may have led to the observed population decline. These same changes were also consistent with population increase in Blue Tits.     

Drivers of low breeding success in the Lesser Spotted Woodpecker Dendrocopos minor in England: testing hypotheses for the decline

Capsule The breeding success of Lesser Spotted Woodpeckers Dendrocopos minor is now lower in England than previously reported and also lower than found in studies elsewhere in Europe.

Aims To quantify the breeding success and identify the causes of nest failure. To test the hypotheses that breeding success is related to aspects of food limitation and parental care, and inclement weather during the nesting period, or to interactions with Great Spotted Woodpeckers.

Methods Nests were monitored in three regions of England, recording survival and causes of failure. We measured aspects of food limitation and parental care, rainfall and Great Spotted Woodpecker interactions at nests, to explore whether there was any evidence that these factors were related to breeding success. We compared results to other studies from the UK and continental Europe.

Results Nest survival was 52%. The average number of chicks produced from successful nests was 2.8. Chick-stage daily nest survival was positively related to provisioning rates, indicating that food supply may be limiting. The most common cause of nest failure was presumed starvation of chicks after the disappearance of an adult. Some females ceased visiting nests, leaving provisioning solely to the male. This behaviour has been reported elsewhere in Europe, but in the present study males were unable to compensate fully by increasing their provisioning rates, leading to poor nest survival. Provisioning rates and chick-stage daily nest survival were negatively associated with rainfall. Nest predation by Great Spotted Woodpeckers occurred but was a less frequent cause of failure. Aggressive interactions were recorded between the two woodpecker species but these were unrelated to breeding parameters.

Conclusions Low breeding success is most probably related to food shortages in the breeding period. Simple population modelling using parameters from the present study and from published work shows that if the low productivity that we have observed is replicated throughout Britain, it would be sufficient to account for the observed population decline. However, the possibility that survival rates are also low cannot be ruled out.     

Characterization of the Cardiac Overexpression of HSPB2 Reveals Mitochondrial and Myogenic Roles Supported by a Cardiac HspB2 Interactome

Small Heat Shock Proteins (sHSPs) are molecular chaperones that transiently interact with other proteins, thereby assisting with quality control of proper protein folding and/or degradation. They are also recruited to protect cells from a variety of stresses in response to extreme heat, heavy metals, and oxidative-reductive stress. Although ten human sHSPs have been identified, their likely diverse biological functions remain an enigma in health and disease, and much less is known about non-redundant roles in selective cells and tissues. Herein, we set out to comprehensively characterize the cardiac-restricted Heat Shock Protein B-2 (HspB2), which exhibited ischemic cardioprotection in transgenic overexpressing mice including reduced infarct size and maintenance of ATP levels. Global yeast two-hybrid analysis using HspB2 (bait) and a human cardiac library (prey) coupled with co-immunoprecipitation studies for mitochondrial target validation revealed the first HspB2 “cardiac interactome” to contain many myofibril and mitochondrial-binding partners consistent with the overexpression phenotype. This interactome has been submitted to the Biological General Repository for Interaction Datasets (BioGRID). A related sHSP chaperone HspB5 had only partially overlapping binding partners, supporting specificity of the interactome as well as non-redundant roles reported for these sHSPs. Evidence that the cardiac yeast two-hybrid HspB2 interactome targets resident mitochondrial client proteins is consistent with the role of HspB2 in maintaining ATP levels and suggests new chaperone-dependent functions for metabolic homeostasis. One of the HspB2 targets, glyceraldehyde 3-phosphate dehydrogenase (GAPDH), has reported roles in HspB2 associated phenotypes including cardiac ATP production, mitochondrial function, and apoptosis, and was validated as a potential client protein of HspB2 through chaperone assays. From the clientele and phenotypes identified herein, it is tempting to speculate that small molecule activators of HspB2 might be deployed to mitigate mitochondrial related diseases such as cardiomyopathy and neurodegenerative disease.     

Patterns of island treeline elevation – a global perspective

Treeline research has strongly focused on mountain systems on the mainland. However, island treelines offer the opportunity to contribute to the global framework on treeline elevation due to their island‐specific attributes such as isolation, small area, low species richness and relative youth. We hypothesize that, similar to the mainland, latitude‐driven temperature variation is the most important determinant of island treeline elevation on a global scale. To test this hypothesis, we compared mainland with island treeline elevations. Then we focused 1) on the global effects of latitude, 2) on the regional effects of island type (continental vs oceanic islands) and 3) the local effects of several specific island characteristics (age, area, maximum island elevation, isolation and plant species richness). We collected a global dataset of islands (n = 86) by applying a stratified design using GoogleEarth and the Global Island Database. For each island we extracted data on latitude and local characteristics. Treeline elevation decreased from the mainland through continental to oceanic islands. Island treeline elevation followed a hump‐shaped latitudinal distribution, which is fundamentally different from the mainland double‐hump. Higher maximum island elevation generated higher treeline elevation and was found the best single predictor of island treeline elevation, even better than latitude. Lower island treeline elevation may be the result of a low mass elevation effect (MEE) influencing island climates and an increasingly impoverished species pool but also trade wind inversion‐associated aridity. The maximum island elevation effect possibly results from an increasing mass elevation effect (MEE) with increasing island elevation but also range shifts during climatic fluctuations and the summit syndrome (i.e. high wind speeds and poor soils in peak regions). Investigating islands in treeline research has enabled disentangling the global effect of latitude from regional and local effects and, at least for islands, a comprehensive quantification of the MEE.