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Cells respond to stimuli by changes in various processes, including signaling pathways and gene expression. Efforts to identify components of these responses increasingly depend on mRNA profiling and genetic library screens, yet the functional roles of the genes identified by these assays often remain enigmatic. By comparing the results of these two assays across various cellular responses, we found that they are consistently distinct. Moreover, genetic screens tend to identify response regulators, while mRNA profiling frequently detects metabolic responses. We developed an integrative approach that bridges the gap between these data using known molecular interactions, thus highlighting major response pathways. We harnessed this approach to reveal cellular pathways related to alpha-synuclein, a small lipid-binding protein implicated in several neurodegenerative disorders including Parkinson disease. For this we screened an established yeast model for alpha-synuclein toxicity to identify genes that when overexpressed alter cellular survival. Application of our algorithm to these data and data from mRNA profiling provided functional explanations for many of these genes and revealed novel relations between alpha-synuclein toxicity and basic cellular pathways.

The genetic library of α-helical amphipathic peptides, 20 amino acid long, was designed and expressed under the T7 promoter in the E. coli JM109(DE3) and BL21 (DE3). Clones that inhibited the growth of the host cell were screened by the relative size of colonies on the plates. Clones which strongly inhibited growth of Escherichia coli JM109(DE3) were further selected. The method developed in this study is useful for the structure activity relationship study of antimicrobial peptides.

This article discusses ecosystem services the importance of rapid information systems to inform human society of needed changes and the need for a monitoring system for warning of hazardous changes in ecosystems. Society must adopt and appreciate the conception of human systems coevolving with natural systems in mutually dependent ways. Natural systems adjust automatically to human society but not necessarily in ways humans intend. Mans relationship to nature is a partnership based on exchanges of benefits and deficits. Human society depends upon the capture of solar energy and conversion into biomass which is used for food building materials and fuel. Other ecosystem services include the decomposition of wastes nitrogen fixation and other processes of plant growth storage and distribution of water generation and maintenance of soils control of pests by species a genetic library for development of new products from Mendelian genetics and bioengineering maintenance of breathable air control of micro- and macro-climate regenerative capacity after natural disasters pollination of plants and aesthetics in nature. Disruptions in ecosystem services are not very obvious when changes are small in scale or improved by technology. The cost of replacing ecosystem services by technology may be an estimated $9 million/person yearly. Human society has five options: 1) continue environmental degradation and population growth; 2) develop a no-net-loss of ecosystem services policy; 3) exceed the standard no-net-loss of ecosystem services and continue population and affluence increases; 4) stabilize human population with a no-net-loss of ecosystem policy; or 5) stabilize human population and its demand on resources and exceed a no-net-loss of ecosystem services. All options will require monitoring. The author suggests three changes in monitoring practices.

Mark Pagel relishes an analysis of how natural selection riffles through life's immense genetic library.