Exploring Human Experience

This essay argues that since human experience consists inseparably of mind, body and the material world, and that if were are to better understand the lives of people in the past we need to recognize that we cannot separate material culture, social process and life-tasks from the experiences of the people who carried them out. Personal experience of a thing can never produce an understanding of that thing that another might have without first discussing who this ?other? is and what their motivations are for being there. The constitution of experience, as an inseparable mix of mind, body and the world prevents the identification, in the present, of ?prehistoric? experiences in the present. An understanding of the theory of human experience can, however, demonstrate that change and the appropriation or alteration of activities and beliefs for new ends can easily be motivated by the power that certain experiences have on us. Thus understanding human experience helps us make new interpretations of the past

Expansion of Signal Transduction Pathways in Fungi by Extensive Genome Duplication

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Expansion of Signal Transduction Pathways in Fungi by Extensive Genome Duplication

[EN] Plants and fungi use light and other signals to regulate development, growth, and metabolism. The fruiting bodies of the fungus Phycomyces blakesleeanus are single cells that react to environmental cues, including light, but the mechanisms are largely unknown [1]. The related fungus Mucor circinelloides is an opportunistic human pathogen that changes its mode of growth upon receipt of signals from the environment to facilitate pathogenesis [2]. Understanding how these organisms respond to environmental cues should provide insights into the mechanisms of sensory perception and signal transduction by a single eukaryotic cell, and their role in pathogenesis. We sequenced the genomes of P. blakesleeanus and M. circinelloides and show that they have been shaped by an extensive genome duplication or, most likely, a whole-genome duplication (WGD), which is rarely observed in fungi [3-6]. We show that the genome duplication has expanded gene families, including those involved in signal transduction, and that duplicated genes have specialized, as evidenced by differences in their regulation by light. The transcriptional response to light varies with the developmental stage and is still observed in a photoreceptor mutant of P. blakesleeanus. A phototropic mutant of P. blakesleeanus with a heterozygous mutation in the photoreceptor gene madA demonstrates that photosensor dosage is important for the magnitude of signal transduction. We conclude that the genome duplication provided the means to improve signal transduction for enhanced perception of environmental signals. Our results will help to understand the role of genome dynamics in the evolution of sensory perception in eukaryotes.European funds (European Regional Development Fund, ERDF); Spanish Ministerio de Economı´a y Competitividad; Junta de Andalucí

Description of three novel Lagenidium (Oomycota) species causing infection in mammals

BACKGROUND: Recent molecular phylogenetic analysis of Lagenidium strains recovered from subcutaneous lesions in cats, dogs, and a human with lagenidiosis resolved into four clades, one of them was Lagenidium giganteum, but three others were novel. AIMS: Due to the recent increase in L. giganteum infections from mammals, we studied 21 Lagenidium strains isolated from dogs and a human available in our collection. METHODS: Molecular phylogenetic studies and phenotypic characteristics were used to characterize strains. RESULTS: We report the finding of three novel species, herein designated as: Lagenidium ajelloi, sp. nov., Lagenidium albertoi sp. nov, and Lagenidium vilelae sp. nov. Their morphological and growth features are also presented. CONCLUSIONS: Our study revealed the presence of three novel Lagenidium species infecting mammals

Expansion of Signal Transduction Pathways in Fungi by Extensive Genome Duplication.

Plants and fungi use light and other signals to regulate development, growth, and metabolism. The fruiting bodies of the fungus Phycomyces blakesleeanus are single cells that react to environmental cues, including light, but the mechanisms are largely unknown [1]. The related fungus Mucor circinelloides is an opportunistic human pathogen that changes its mode of growth upon receipt of signals from the environment to facilitate pathogenesis [2]. Understanding how these organisms respond to environmental cues should provide insights into the mechanisms of sensory perception and signal transduction by a single eukaryotic cell, and their role in pathogenesis. We sequenced the genomes of P. blakesleeanus and M. circinelloides and show that they have been shaped by an extensive genome duplication or, most likely, a whole-genome duplication (WGD), which is rarely observed in fungi [3-6]. We show that the genome duplication has expanded gene families, including those involved in signal transduction, and that duplicated genes have specialized, as evidenced by differences in their regulation by light. The transcriptional response to light varies with the developmental stage and is still observed in a photoreceptor mutant of P. blakesleeanus. A phototropic mutant of P. blakesleeanus with a heterozygous mutation in the photoreceptor gene madA demonstrates that photosensor dosage is important for the magnitude of signal transduction. We conclude that the genome duplication provided the means to improve signal transduction for enhanced perception of environmental signals. Our results will help to understand the role of genome dynamics in the evolution of sensory perception in eukaryotes