AND IF ENGLER WAS NOT COMPLETELY WRONG? EVIDENCE FOR MULTIPLE EVOLUTIONARY ORIGINS IN THE MOSS FLORA OF MACARONESIA

The Macaronesian endemic flora has traditionally been interpreted as a relict of a subtropical element that spanned across Europe in the Tertiary. This hypothesis is revisited in the moss subfamily Helicodontioideae based on molecular divergence estimates derived from two independent calibration techniques either employing fossil evidence or using an Monte Carlo Markov Chain (MCMC) to sample absolute rates of nucleotide substitution from a prior distribution encompassing a wide range of rates documented across land plants. Both analyses suggest that the monotypic Madeiran endemic genus Hedenasiastrum diverged of other Helicodontioideae about 40 million years, that is, well before Macaronesian archipelagos actually emerged, in agreement with the relict hypothesis. Hedenasiastrum is characterized by a plesiomorphic morphology, which is suggestive of a complete morphological stasis over 40 million years. Macaronesian endemic Rhynchostegiella species, whose polyphyletic origin involves multiple colonization events, evolved much more recently, and yet accumulated many more morphological novelties than H. percurrens. The Macaronesian moss flora thus appears as a complex mix of ancient relicts and more recently dispersed, fast‐evolving taxa.     

The circadian gene Cryptochrome 2 influences stress-induced brain activity and depressive-like behavior in mice

Cryptochrome 2 (Cry2) is a core clock gene important for circadian regulation. It has also been associated with anxiety and depressive-like behaviors in mice, but the previous findings have been conflicting in terms of the direction of the effect. To begin to elucidate the molecular mechanisms of this association, we carried out behavioral testing, PET imaging, and gene expression analysis of Cry2^−/− and Cry2^+/+ mice. Compared to Cry2^+/+ mice, we found that Cry2^−/− mice spent less time immobile in the forced swim test, suggesting reduced despair-like behavior. Moreover, Cry2^−/− mice had lower saccharin preference, indicative of increased anhedonia. In contrast, we observed no group differences in anxiety-like behavior. The behavioral changes were accompanied by lower metabolic activity of the ventro-medial hypothalamus, suprachiasmatic nuclei, ventral tegmental area, anterior and medial striatum, substantia nigra, and habenula after cold stress as measured by PET imaging with a glucose analog. Although the expression of many depression-associated and metabolic genes was upregulated or downregulated by cold stress, we observed no differences between Cry2^−/− and Cry2^+/+ mice. These findings are consistent with other studies showing that Cry2 is required for normal emotional behavior. Our findings confirm previous roles of Cry2 in behavior and extend them by showing that the effects on behavior may be mediated by changes in brain metabolism.     

A new efficient expression system for Bacillus and its application to production of recombinant phytase

A new expression system was developed for Bacillus subtilis.This system uses a shuttle vector (B. subtilis– Eschericia coli) carrying a phosphate starvation-inducible promoter (pst) and on a fed-batch cultivation strategy. The pst-promoter proved to be very strong and retain its tight regulation also when present on a multi-copy plasmid. The expression system developed showed promising results when applied to the production of recombinant Bacillusphytase – phytase activity at the end of cultivation reached 28.7 U ml^–1.     

A small marine biosphere in the Proterozoic

The riverine supply of the globally limiting nutrient, phosphorus, to the ocean accounts for only a few percent of nutrient supply to photosynthetic organisms in surface waters. Recycling of marine organic matter by heterotrophic organisms provides almost all of the phosphorus that drives net primary production in the modern ocean. In the low‐oxygen environments of the Proterozoic, the lack of free oxygen would have limited rates of oxic respiration, slowing the recycling of nutrients and thus limiting global rates of photosynthesis. A series of steady‐state mass balance calculations suggest that the rate of net primary production in the ocean was no more than 10% of its modern value during the Proterozoic eon, and possibly less than 1%. The supply of nutrients in such a world would be dominated by river input, rather than recycling within the water column, leading to a small marine biosphere found primarily within estuarine environments.     

Chemical neurotransmission in the parkinsonian brain

In Parkinson's disease the progressive loss of nigrostriatal dopamine neurons leads to striatal dopamine deficiency and correlates with the severity of parkinsonian disability. The findings concerning dopamine receptors both in vitro and in vivo are not consistent, possibly reflecting differences in patient populations, but the presynaptic defect in dopaminergic neurotransmission is greater than that seen in postsynaptic receptor binding studies. The cholinergic neurons in the extrapyramidal nuclei are relatively well preserved, but subcortico-cortical and -hippocampal cholinergic neurons degenerate in relation to the degree of dementia. The decreased GABA receptor binding in the parkinsonian substantia nigra possibly reflects the loss of nigral dopamine neurons, since nigral GABA receptors are located on these neurons. Of the various neuropeptides, the concentration of met- and leu-enkephalin seems to be reduced in the striatum. In the substantia nigra the concentration of substance P decreases, together with the met-enkephalin and cholecystokinin levels. The concentration of somatostatin decreases in the frontal cortex and hippocampus of demented patients. With the exception of the association between cortical somatostatin deficiency and intellectual deterioration, the role of the neuropeptides in the pathophysiology and clinical features of Parkinson's disease are not yet fully understood.     

Coccygeus and levator ani muscles in the rabbit: morphology and proprioceptive innervation

The Authors have studied the morphological features and the proprioceptive nervous component in the coccygeus and levator ani muscles of the rabbit, using Ruffini's and Barker-Ip's impregnations. The coccygeus muscle originates from ischiatic spine and inserts on the last three sacral vertebrae and on the first four or five caudal vertebrae. The levator ani muscle originates from the ischiatic spine and the coccygeus muscle aponeurosis and inserts directly on the caudal vertebrae 3-5 or 4-6. The proprioceptive innervation in both muscles is constituted by muscle spindles and Golgi tendon organs with a typical structure. Muscle spindles are more numerous than Golgi tendon organs and the spindle density is higher in the levator ani muscle.     

Advanced Biofuels from Thermochemical Processing of Sustainable Biomass in Europe

Biofuels can play an important role in decreasing the use of fossil fuels, in particular in the transport sector, which absorbs about 30 % of the EU energy requirements. This review illustrates the motivations behind biofuel development, the government incentives and regulations and the current approaches on sustainable biomass conversion in Europe, and provides an overview on the major steps involved in thermochemical processes and on the issues challenging their deployment at large scale, with particular emphasis on the pyrolysis of biomass and bio-oil upgrading using conventional oil refinery settings. Distribution of sustainable biofuels in Europe and future prospects towards achieving success of transport biofuels were also addressed. The literature suggests that importing biofuels and increasing the cost of CO₂ to at least €60/t CO₂ will be necessary to meet the renewable obligation targets in the EU. Algae represent the future feedstock for biofuels but currently are limited by their high production costs and high N content. Pyrolysis is cost competitive compared to other technologies such as fermentation and gasification, but the quality of bio-oils requires upgrading mainly to lower their oxygen content and enhance their thermal stability. The recent advances in bio-oil upgrading using catalytic cracking and hydro-treating are very promising for the future deployment of advanced biofuels in the coming decades. However, significant investments in applied research and demonstration are still required to meet the 2020/2030 biofuel targets.     

ECOLOGICAL VERSUS PHYLOGENETIC DETERMINANTS OF TROPHIC ASSOCIATIONS IN A PLANT–LEAFMINER–PARASITOID FOOD WEB

Specialized trophic interactions in plant–herbivore–parasitoid food webs can spur “bottom–up” diversification if speciation in plants leads to host‐shift driven divergence in insect herbivores, and if the effect then cascades up to the third trophic level. Conversely, parasitoids that search for victims on certain plant taxa may trigger “top–down” diversification by pushing herbivores into “enemy‐free space” on novel hosts. We used phylogenetic regression methods to compare the relative importance of ecology versus phylogeny on associations between Heterarthrinae leafmining sawflies and their parasitoids. We found that: (1) the origin of leafmining led to escape from most parasitoids attacking external‐feeding sawflies; (2) the current enemies mainly consist of generalists that are shared with other leafmining taxa, and of more specialized lineages that may have diversified by shifting among heterarthrines; and (3) parasitoid–leafminer associations are influenced more by the phylogeny of the miners’ host plants than by relationships among miner species. Our results suggest that vertical diversifying forces have a significant—but not ubiquitous—role in speciation: many of the parasitoids have remained polyphagous despite niche diversification in the miners, and heterarthrine host shifts also seem to be strongly affected by host availability.