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The study of the reproductive biology of lichen fungal symbionts has been traditionally challenging due to their complex and symbiotic lifestyles. Against the common belief of haploidy, a recent genomic study found a triploid-like signal inLetharia. Here, we used genomic data from a pure culture and from thalli, together with a PCR survey of the MAT locus, to infer the genome organization and reproduction inLetharia. We found that the read count variation in the fourLethariaspecimens, including the pure culture derived from a single sexual spore ofL. lupina, is consistent with haploidy. By contrast, theL. lupinaread counts from a thallus’ metagenome are triploid-like. Characterization of the mating-type locus revealed a conserved heterothallic configuration across the genus, along with auxiliary genes that we identified. We found that the mating-type distributions are balanced in North America forL. vulpinaandL. lupina, suggesting widespread sexual reproduction, but highly skewed in Europe forL. vulpina, consistent with predominant asexuality. Taken together, we propose thatLethariafungi are heterothallic and typically haploid, and provide evidence that triploid-like individuals are rare hybrids betweenL. lupinaand an unknownLetharialineage, reconciling classic systematic and genetic studies with recent genomic observations.

Soil pollution has been estimated using soil analysis and leaching test. These methods could show different data from reality due to effects by soil properties such as grain size and mineral composition. Therefore, this study advocates a new assessment and monitoring method of heavy metal polluted soil using fruticose lichens. Lichens growing at abandoned mine sites and unpolluted areas in southwest Japan and their substrata were analyzed using inductively coupled plasma-mass spectrometry and X-ray fluorescence spectrometry to clarify the relationships between the heavy metal concentrations in lichens and soils, and their heavy metal absorption properties. Concentrations of Cu, Zn, As, and Pb in the lichens were positively correlated with those in the soil. Variability of the relationships did not depend on the lichen species, location, habitat, or the conditions of soils. The analyzed lichens had neither competitive nor antagonistic properties in their heavy metal absorption, which make them good biomarkers of heavy metal pollution of soil. The distribution maps of average heavy metal concentrations at each sampling region detected almost all of the Cu, Zn, and As pollution of soil. Therefore, lichens could be used in practical applications to assess Cu, Zn, and As pollution of soils.

Delimiting species boundaries among closely related lineages often requires a range of independent data sets and analytical approaches. Similar to other organismal groups, robust species circumscriptions in fungi are increasingly investigated within an empirical framework. Here we attempt to delimit species boundaries in a closely related clade of lichen-forming fungi endemic to Asia, the Hypogymnia hypotrypa group (Parmeliaceae). In the current classification, the Hypogymnia hypotrypa group includes two species: H. hypotrypa and H. flavida, which are separated based on distinctive reproductive modes, the former producing soredia but absent in the latter. We reexamined the relationship between these two species using phenotypic characters and molecular sequence data (ITS, GPD, and MCM7 sequences) to address species boundaries in this group. In addition to morphological investigations, we used Bayesian clustering to identify potential genetic groups in the H. hypotrypa/H. flavida clade. We also used a variety of empirical, sequence-based species delimitation approaches, including: the "Automatic Barcode Gap Discovery" (ABGD), the Poisson tree process model (PTP), the General Mixed Yule Coalescent (GMYC), and the multispecies coalescent approach BPP. Different species delimitation scenarios were compared using Bayes factors delimitation analysis, in addition to comparisons of pairwise genetic distances, pairwise fixation indices (FST). The majority of the species delimitation analyses implemented in this study failed to support H. hypotrypa and H. flavida as distinct lineages, as did the Bayesian clustering analysis. However, strong support for the evolutionary independence of H. hypotrypa and H. flavida was inferred using BPP and further supported by Bayes factor delimitation. In spite of rigorous morphological comparisons and a wide range of sequence-based approaches to delimit species, species boundaries in the H. hypotrypa group remain uncertain. This study reveals the potential limitations of relying on distinct reproductive strategies as diagnostic taxonomic characters for Hypogymnia and also the challenges of using popular sequence-based species delimitation methods in groups with recent diversification histories.

Severe influenza is characterized by cytokine storm and multiorgan failure with metabolic energy disorders and vascular hyperpermeability. In the regulation of energy homeostasis, the pyruvate dehydrogenase (PDH) complex plays an important role by catalyzing oxidative decarboxylation of pyruvate, linking glycolysis to the tricarboxylic acid cycle and fatty acid synthesis, and thus its activity is linked to energy homeostasis. The present study tested the effects of diisopropylamine dichloroacetate (DADA), a new PDH kinase 4 (PDK4) inhibitor, in mice with severe influenza. Infection of mice with influenza A PR/8/34(H1N1) virus resulted in marked down-regulation of PDH activity and ATP level, with selective up-regulation of PDK4 in the skeletal muscles, heart, liver and lungs. Oral administration of DADA at 12-h intervals for 14 days starting immediately after infection significantly restored PDH activity and ATP level in various organs, and ameliorated disorders of glucose and lipid metabolism in the blood, together with marked improvement of survival and suppression of cytokine storm, trypsin up-regulation and viral replication. These results indicate that through PDK4 inhibition, DADA effectively suppresses the host metabolic disorder-cytokine cycle, which is closely linked to the influenza virus-cytokine-trypsin cycle, resulting in prevention of multiorgan failure in severe influenza.

To improve knowledge of heavy metals accumulated in Adelie penguins (Pygoscelis adeliae), concentrations of Cd, Cu, Zn, Hg, Pb, Se, Mn and Fe were measured in livers, kidneys, muscles, skin and feathers collected from 12 chicks and 11 adult penguins which were captured at breeding sites at Cape Hinode and in Hukuro Cove during the chick-rearing period, from 1 January to 9 February, 1991. Antarctic krills (Euphausia superba) collected from the stomach content of adult penguins were also analyzed. Higher concentrations of heavy metals were found in the liver and kidney than in other tissues. The average trace element concentrations of adult penguins were in the order Fe(635 μg/g wet)>Zn(29.3)>Cu(6.4)>Mn(2.1)>Cd(1.9)>Se(1.4)>Pb(0.31)>Hg(0.18) for the liver, and Fe(280)>Zn(29.8)>Cd (14.7)>Cu(3.5)>Se(2.7)>Mn(1.2)>Hg(0.16)>Pb(0.13) for the kidney. Cadmium and Hg concentrations in the liver, kidney, muscle and skin of Adelie penguins increased with growth; this fact suggests that Cd and Hg were accumulated in the body through food. The Fe concentrations of adults were significantly higher in both pectoral and femoral muscles than those of the chicks (t-test, p

2-(2-Thiazolylazo)-4-methoxyphenol (TAMP) forms a brownish 2:1 complex with iron(ll) in the presence of ascorbic acid; the complex has a characteristic absorption at 784 nm in chloroform. By utilizing this peculiar absorption, selective spectrophotometry determination of iron has been developed. The optimum pH for iron extraction lies between 5.0-9.3 and Beer's law holds up to 5.0 ng/ml of iron. Many type of ions are tolerable. The method was successfully applied to the determination of iron in river waters. The extraction constant of iron(ll) complex was log Kex=-2.50±0.12 and the extraction mechanism was kinetically investigated. The complexation rate was first-order with respect to iron(ll) and TAMP concentrations and independent of ascorbic acid concentration. From these results, the major extraction rate-determining step was concluded to be a 1:1 complexation reaction between iron(ll) and dissociated TAMP. Kinetic data and activation parameters for the first-order reaction were determined and discussed. © 1988, The Japan Society for Analytical Chemistry. All rights reserved.