Molecular phylogeny of the fungus gnat tribe Exechiini (Mycetophilidae, Diptera)

The phylogenetic relationships within the fungus gnat tribe Exechiini have been left unattended for many years. Recent studies have not shed much light on the intergeneric relationship within the tribe. Here the first attempt to resolve the phylogeny of the tribe Exechiini using molecular markers is presented. The nuclear 18S and the mitochondrial 16S, and cytochrome oxidase subunit I (COI) genes were successfully sequenced for 20 species representing 15 Exechiini genera and five outgroup genera. Bayesian, maximum parsimony and maximum likelihood analyses revealed basically congruent tree topologies and the monophyly of Exechiini, including the genus Cordyla , is confirmed. The molecular data corroborate previous morphological studies in several aspects. Cordyla is found in a basal clade together with Brachypeza , Pseudorymosia and Stigmatomeria . The splitting of the genera Allodiopsis s.l. and Brevicornu s.l. as well as the sistergroup relationship of Exechia and Exechiopsis is also supported. The limited phylogenetic information provided by morphological characters is mirrored in the limited resolution of the molecular markers used in this study. Short internal and long-terminal branches obtained may indicate a rapid radiation of the Exechiini genera during a short evolutionary period.     

Genes of the R-phycocyanin II locus of marine Synechococcus spp., and comparison of protein-chromophore interactions in phycocyanins differing in bilin composition

R-phycocyanin II (RPCII) is a recently discovered member of the phycocyanin family of photosynthetic light-harvesting proteins. Genes encoding the and subunits of RPCII were cloned and sequenced from marine Synechococcus sp. strains WH8020 and WH8103. The deduced amino acid sequences of RPCII were compared to two other types of phycocyanin, C-phycocyanin (CPC) and phycoerythrocyanin (PEC). These three types vary in the composition of their covalently bound bilin prosthetic groups. In terms of amino acid sequence identity RPCII is highly homologous to CPC and PEC, suggesting that the known three-dimensional structures of the latter two are representative of RPCII. Thus the amino acid residues contacting the three bilins of RPCII could be inferred and compared to those in CPC and PEC. Certain residues were identified among the three phycocyanins as possibly correlating with specific bilin isomers. In overall sequence RPCII and CPC are more homologous to one another than either is to PEC. This probably reflects functional homology in the roles of RPCII and CPC in the transfer of light energy to the core of the phycobilisome, a function not attributed to PEC. The genomes of Synechococcus sp. strains WH8020, WH8103 and WH7803 share homologous open reading frames in the vicinity of RPCII genes. The nucleotide sequence extending 3 from RPCII genes in strain WH8020 revealed two open reading frames homologous to components of an CPC phycocyanobilin lyase. These open reading frames may encode a lyase specific for the attachment of phycoerythrobilin to RPCII.     

Alchemilla austriaca,spec. nova,(Rosaceae) — eine neue Art aus den Ostalpen

Alchemilla austriaca is a new species which belongs to the group ofA. demissa, A. frigens, A. longana, A. longiuscula, A. semisecta, andA. sinuata. The holotype specimen as well as leaf and flower details are illustrated (Figs. 1–3). A complete character analysis is given, differences and similarities of allied species are presented in two tables, and the position of the group within the genus is discussed.A. austriaca so far is known only from the Austrian Alps and mainly from the central ranges (distribution map: Fig. 4). Its wet subalpine and alpine habitats are characterized by species lists.

     

Characterisation of the endospermal trypsin inhibitor of barley

A trypsin inhibitor was isolated from grains of two row barley (cv. Proctor). The purified protein was identical with the corresponding inhibitor of a six row barley (cv. Pirkka); both proteins showed, a Pi of 7.4. The N-terminal amino acid was phenylalanine and an arginine residue was involved in the active site. Effects of substrate concentration showed that the inhibition was noncompetitive with a K_i of about 0.9 × 10^?7M. An enzyme-inhibitor complex was demonstrated by disc electrophoresis.     

L value determination under paddy soil condition

Summary The L values of four paddy soils and one United Kingdom soil were determined under water-logged and aerobic conditions over a period of 7 weeks using rice and ryegrass as the respective test crops.Under water-logged conditions, the L values attained a constant level in the course of the growing period, indicating that isotopic equilibrium between the added P³² and the soil was achieved.Under aerobic conditions, the equilibrium L values tended to be lower than those determined under water-logged conditions.This was taken as an indication of an increase of labile soil phosphorus by reduction of ferric iron.     

FEMALE PROMISCUITY IS POSITIVELY ASSOCIATED WITH NEUTRAL AND SELECTED GENETIC DIVERSITY IN PASSERINE BIRDS

Passerine birds show large interspecific variation in extrapair paternity rates. There is accumulating evidence that such promiscuous behavior is driven by indirect, genetic benefits to females. Sexual selection theory distinguishes between two types of genetic benefits, additive and nonadditive effects, mediated by preferences for good and compatible genes, respectively. Good genes preferences should imply directional selection and mating skew among males, and thus reduced genetic diversity in the population. In contrast, compatible genes preferences should give balancing selection that retains genetic diversity. Here, we test how well these predictions fit with patterns of variation in genetic diversity and promiscuity levels among passerine birds. We found that more promiscuous species had higher nucleotide diversity at autosomal introns, but not at Z‐chromosome introns. We also found that major histocompatibility complex (MHC) class IIB alleles had higher sequence diversity, and therefore should recognize a broader spectrum of pathogens, in more promiscuous species. Our results suggest that female promiscuity targets a multitude of autosomal genes for their nonadditive, compatibility benefits. Also, as immunity genes seem to be of particular importance, we hypothesize that interspecific variation in female promiscuity among passerine birds has arisen in response to the strength of pathogen‐mediated selection.     

Susceptibility of brown adipocytes to pro-inflammatory cytokine toxicity and reactive oxygen species

Brown adipose tissue (BAT) cells have a very high oxidative capacity. On the other hand, in obesity and obesity-related diabetes, levels of pro-inflammatory cytokines are elevated, which might promote BAT dysfunction and consequently impair carbohydrate metabolism and thereby exacerbate cellular dysfunction and promote diabetes progression. Therefore, the antioxidative enzyme status of a brown adipocyte cell line and its susceptibility towards pro-inflammatory cytokines, which participate in the pathogenesis of diabetes, and reactive oxygen species (ROS) were analysed. Mature brown adipocytes exhibited significantly higher levels of expression of mitochondrially and peroxisomally located antioxidative enzymes compared with non-differentiated brown adipocytes. Pro-inflammatory cytokines induced a significant decrease in the viability of differentiated brown adipocytes, which was accompanied by a massive ROS production and down-regulation of BAT-specific markers, such as uncoupling protein 1 (UCP-1) and β-Klotho. Taken together, the results strongly indicate that pro-inflammatory cytokines cause brown adipocyte dysfunction and death through suppression of BAT-specific proteins, especially of UCP-1 and β-Klotho, and consequently increased oxidative stress.