A genetic linkage map of the fungus Phycomyces blakesleeanus

Comparative Medicine - OneHealth and Comparative Medicine Poster SessionPhycomyces blakesleeanus is a filamentous fungus of research interest because of its ability to sense and respond to its environment. The unicellular sporangiophores show growth responses to light, gravity, wind, chemicals and presence of objects near the growing zone. The mycelium also shows responses by induction of β-carotene synthesis and initiation of sporangiophores. The responses to light have been most carefully analyzed, in part driven by the efforts of Nobel laureate Max Delbrück who tried to develop Phycomyces into the “phage of vision”. Strains with impaired phototropism (mad) were isolated in the 1960s-1980s, as well as mutants affected in other sensory responses or phenotypes. These properties have made Phycomyces a model of sensory transduction processes. However, the inability to transform DNA into Phycomyces has blocked the identification of genes in this fungus. To identify genes in this fungus, a map-based cloning approach is underway. A genetic map of Phycomyces based on mutant phenotypes and tetrad analysis was generated over a 20 year time frame. The new genetic map of Phycomyces is constructed largely from amplified fragment length polymorphism of progeny derived from a cross between two wild type strains. 78 markers have been developed and used in PCR analysis to assign alleles from the mapping population. Markers spacing a collective total of 7.1 Mb exhibited a total of 247 map units of recombination (centiMorgans, cM). The average is 1 cM = 29 kb, with a range of 1 cM = 8 kb to 1 cM = 106 kb. With the Phycomyces genome comprising an estimated 55 Mb, 190 markers are required for complete coverage with 10 cM resolution. This map has already been used to narrow the search for mad genes, with the identification of point mutations in furA and lysA genes that flank madD and madE, respectively. Additionally, using the carRA and carB genes as a starting point, the DNA regions near the madI gene have been found and the adjacent carS gene identified

Photosensing Fungi: Phytochrome in the Spotlight

Red light triggers asexual development and represses sexual development in the fungus Aspergillus nidulans. This response has been shown to require a phytochrome red/far-red light photoreceptor, FphA, which is cytoplasmic and binds a tetrapyrrole chromophore. FphA exhibits similarities to both plant and bacterial phytochromes

Ferrochelatase is a conserved downstream target of the blue light-sensing White collar complex in fungi

Light is a universal signal perceived by organisms, including fungi, in which light regulates common and unique biological processes depending on the species. Previous research has established that conserved proteins, originally called White collar 1 and 2 from the ascomycete Neurospora crassa, regulate UV/blue light sensing. Homologous proteins function in distant relatives of N. crassa, including the basidiomycetes and zygomycetes, which diverged as long as a billion years ago. Here we conducted microarray experiments on the basidiomycete fungus Cryptococcus neoformans to identify light-regulated genes. Surprisingly, only a single gene was induced by light above the commonly used twofold threshold. This gene, HEM15, is predicted to encode a ferrochelatase that catalyses the final step in haem biosynthesis from highly photoreactive porphyrins. The C. neoformans gene complements a Saccharomyces cerevisiae hem15Δ strain and is essential for viability, and the Hem15 protein localizes to mitochondria, three lines of evidence that the gene encodes ferrochelatase. Regulation of HEM15 by light suggests a mechanism by which bwc1/bwc2 mutants are photosensitive and exhibit reduced virulence. We show that ferrochelatase is also light-regulated in a white collar-dependent fashion in N. crassa and the zygomycete Phycomyces blakesleeanus, indicating that ferrochelatase is an ancient target of photoregulation in the fungal kingdom

Tao3 mediates a phenotypic switch between amoeba-adapted and mammalian-adapted forms of Cryptococcus neoformans

Comparative Medicine - OneHealth and Comparative Medicine Poster SessionMany microbes are capable of changing phenotypes more frequently than due to basal mutation rates alone, and this ability is coupled to pathogenesis. The human pathogenic yeast Cryptococcus neoformans is found in the environment in soil, pigeon guano and tree species, locations in which the organism is exposed to microbial predators. Previous research showed that co-incubation of C. neoformans with amoeba causes a switch from a yeast to a pseudohyphal form, enabling fungal survival in amoeba yet conversely reducing virulence in mammalian models of cryptococcosis. We identify the basis for pseudohyphal development in phenotypic-switched and amoeba-derived strains, to show that genes encoding proteins of the RAM (Regulation of Ace2p activity and cellular Morphogenesis) pathway bear mutations. Reversion to wild type yeast morphology can occur through multiple different mechanisms to suggest that underlying rates of spontaneous mutation control this process and thereby influence the pathogenic potential of an organism

Discrete analysis for single-pylon suspension bridges

This paper presents calculation methods, developed at Tallinn University of Technology (Idnurm 2004; Kulbach 2007), for the single-pylon suspension bridges stiffened by a girder. Classical suspension bridge consists of a geometrically non-linear cable, connected by hangers with an elastic linear stiffening girder, pylons in both ends of the bridge and anchor cables. Alternate form of a suspension bridge is a bridge, with only one pylon on the middle of the span and suspension cable is connected to the abutments or the ends of the stiffening girder. In the calculation of suspension bridges, the geometrically non-linear behaviour of the parabolic cable is the main problem. The linear methods of analysis suit only for small spans. A geometrically non-linear continual model is especially useful for classical loading cases – a uniformly distributed load on the whole or half span. But the modern traffic models consist of concentrated and uniformly distributed loads. The discrete model of a suspension bridge allows us to apply all kinds of loads, such as distributed or concentrated ones. The assumptions of the discrete method described here are: linear elastic strain-stress dependence of the material and absence of horizontal displacements of hangers. Hanger elongation is taken into account. Kabamojo tilto su vienu pilonu diskrečioji analizė Santrauka Straipsnyje pateikiamas skaičiavimo metodas, pasiūlytas Talino technikos universiteto mokslininkų (Idnurm 2004; Kulbach 2007) ir skirtas kabamųjų tiltų su vienu pilonu standumo sijai skaičiuoti. Klasikiniai kabamieji tiltai susideda iš geometriškai nietiesiško lyno, kuris tampriomis atotampomis sujungtas su standumo sija. Paprastai lynas būna pakabintas tarp dviejų pilonų, inkaruotų inkariniais lynais. Alternatyvi kabamųjų tiltų konstrukcija yra tokia, kai naudojamas tik vienas pilonas tilto viduryje, o pagrindinis geometriškai netiesiškas lynas yra inkaruojamas standumo sijos galuose. Skaičiuojant kabamuosius tiltus, pagrindinė problema yra parabolinio lyno geometrinio netiesiškumo elgsena. Tiesinė analizė tinkama tik mažiems tarpatramiams. Geometrinio netiesiškumo modelis ypač naudingas klasikinės apkrovos atveju – vienodai išskirstytai apkrovai visam arba pusei tarpatramio. Tačiau šiuolaikinius transporto modelius sudaro koncentruotos ir vienodai išskirstytos apkrovos. Diskretusis kabamojo tilto modelis leidžia mums taikyti visų tipų apkrovas, tokias kaip koncentruotos ir išskirstytos. Diskrečiojo modelio prielaidos yra tokios: taikoma medžiagų ir horizontalių atotampų poslinkių tiesinė įtempių ir deformacijų priklausomybė. Atotampų pailgėjimas taip pat yra įvertintas. First Published Online: 16 May 2013 Reikšminiai žodžiai: lynų konstrukcijos, standumo sijos, kabamasis lynas, didelių tarpatramių konstrukcijos, diskrečioji analizė, geometrinis netiesiškuma

Transcriptomic responses of the basidiomycete yeast Sporobolomyces sp. to the mycotoxin patulin

Unprocessed Cuffdiff output of the RNAseq experiments performed for Sporobolomyces grown in the presence of 5 μg/ml of PAT. Where no Sporobolomyces gene models are indicated based on the previous JGI annotation (column C), it indicates a novel transcript identified following the transcriptomic analysis presented in this study. (XLSX 1622 kb

Life cycle analysis of reinforced concrete bridges in Baltic countries

During this paper the first part of Life Cycle Analysis based on visual inspection data of main types of reinforced concrete bridges in Baltic countries will be introduced and discussed. In a first step, the background of bridge management systems, visual inspections and most common bridges will be presented. During this step, an explanation of differences and similarities of Baltics visual inspections and data processing will be introduced. In a second step, principal component analysis with main outcomes for different Baltic countries and possible reasons for those outcomes will be discussed. Also a comparison of principal components for similar bridges in all Baltic countries will be shown. At the end, input for predictive models will be introduced. The main objective of this input is to show what elements deteriorate more rapidly and due to that have an influence for Life Cycle of reinforced concrete bridgesThe authors would like to gratefully acknowledge supporting of TU1406 – Quality specifications for roadway bridges, standardization at a European level (BridgeSpec), a COST Action supported by EU Framework Programme Horizon 2020.info:eu-repo/semantics/publishedVersio

A glimpse into the basis of vision in the kingdom Mycota

Virtually all organisms exposed to light are capable of sensing this environmental signal. In recent years the photoreceptors that mediate the ability of fungi to " see" have been identified in diverse species, and increasingly characterized. The small sizes of fungal genomes and ease in genetic and molecular biology manipulations make this kingdom ideal amongst the eukaryotes for understanding photosensing. The most widespread and conserved photosensory protein in the fungi is White collar 1 (WC-1), a flavin-binding photoreceptor that functions with WC-2 as a transcription factor complex. Other photosensory proteins in fungi include opsins, phytochromes and cryptochromes whose roles in fungal photobiology are not fully resolved and their distribution in the fungi requires further taxon sampling. Additional unknown photoreceptors await discovery. This review discusses the effects of light on fungi and the evolutionary processes that may have shaped the ability of species to sense and respond to this signal.United States National Institutes of Health K22 AI073917National Science Foundation MCB-0920581Ministerio de Ciencia e Innovación BIO2009-12486Junta de Andalucía P06-CVI-01650, P09-CVI-502

Alaealiste õigusrikkujate erikohtlemise süsteemi rakendamise vajalikkus ja kavandatavad muudatused Eestis väärteomenetluse seadustiku raames

http://www.ester.ee/record=b468628

Adaptive Response to DNA-Damaging Agents in Natural Saccharomyces cerevisiae Populations from “Evolution Canyon”, Mt. Carmel, Israel

BACKGROUND:Natural populations of most organisms, especially unicellular microorganisms, are constantly exposed to harsh environmental factors which affect their growth. UV radiation is one of the most important physical parameters which influences yeast growth in nature. Here we used 46 natural strains of Saccharomyces cerevisiae isolated from several natural populations at the "Evolution Canyon" microsite (Nahal Oren, Mt. Carmel, Israel). The opposing slopes of this canyon share the same geology, soil, and macroclimate, but they differ in microclimatic conditions. The interslope differences in solar radiation (200%-800% more on the "African" slope) caused the development of two distinct biomes. The south-facing slope is sunnier and has xeric, savannoid "African" environment while the north-facing slope is represented by temperate, "European" forested environment. Here we studied the phenotypic response of the S. cerevisiae strains to UVA and UVC radiations and to methyl methanesulfonate (MMS) in order to evaluate the interslope effect on the strains' ability to withstand DNA-damaging agents. METHODOLOGY/PRINCIPAL FINDINGS:We exposed our strains to the different DNA-damaging agents and measured survival by counting colony forming units. The strains from the "African" slope were more resilient to both UVA and MMS than the strains from the "European" slope. In contrast, we found that there was almost no difference between strains (with similar ploidy) from the opposite slopes, in their sensitivity to UVC radiation. These results suggest that the "African" strains are more adapted to higher solar radiation than the "European" strains. We also found that the tetraploids strains were more tolerant to all DNA-damaging agents than their neighboring diploid strains, which suggest that high ploidy level might be a mechanism of adaptation to high solar radiation. CONCLUSIONS/SIGNIFICANCE:Our results and the results of parallel studies with several other organisms, suggest that natural selection appears to select, at a microscale, for adaptive complexes that can tolerate the higher UV radiation on the "African" slope