34 research outputs found

    Functional olfactory evolution in Drosophila suzukii and the subgenus Sophophora

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    Comparative analysis of multiple genomes has been used extensively to examine the evolution of chemosensory receptors across the genus Drosophila. However, few studies have delved into functional characteristics, as most have relied exclusively on genomic data alone, especially for non-model species. In order to increase our understanding of olfactory evolution, we have generated a comprehensive assessment of the olfactory functions associated with the antenna and palps for Drosophila suzukii as well as several other members of the subgenus Sophophora, thus creating a functional olfactory landscape across a total of 20 species. Here we identify and describe several common elements of evolution, including consistent changes in ligand spectra as well as relative receptor abundance, which appear heavily correlated with the known phylogeny. We also combine our functional ligand data with protein orthologue alignments to provide a high-throughput evolutionary assessment and predictive model, where we begin to examine the underlying mechanisms of evolutionary changes utilizing both genetics and odorant binding affinities. In addition, we document that only a few receptors frequently vary between species, and we evaluate the justifications for evolution to reoccur repeatedly within only this small subset of available olfactory sensory neurons

    CRTC Potentiates Light-independent timeless Transcription to Sustain Circadian Rhythms in Drosophila

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    Light is one of the strongest environmental time cues for entraining endogenous circadian rhythms. Emerging evidence indicates that CREB-regulated transcription co-activator 1 (CRTC1) is a key player in this pathway, stimulating light-induced Period1 (Per1) transcription in mammalian clocks. Here, we demonstrate a light-independent role of Drosophila CRTC in sustaining circadian behaviors. Genomic deletion of the crtc locus causes long but poor locomotor rhythms in constant darkness. Overexpression or RNA interference-mediated depletion of CRTC in circadian pacemaker neurons similarly impairs the free-running behavioral rhythms, implying that Drosophila clocks are sensitive to the dosage of CRTC. The crtc null mutation delays the overall phase of circadian gene expression yet it remarkably dampens light-independent oscillations of TIMELESS (TIM) proteins in the clock neurons. In fact, CRTC overexpression enhances CLOCK/CYCLE (CLK/CYC)-activated transcription from tim but not per promoter in clock-less S2 cells whereas CRTC depletion suppresses it. Consistently, TIM overexpression partially but significantly rescues the behavioral rhythms in crtc mutants. Taken together, our data suggest that CRTC is a novel co-activator for the CLK/CYC-activated tim transcription to coordinate molecular rhythms with circadian behaviors over a 24-hour time-scale. We thus propose that CRTC-dependent clock mechanisms have co-evolved with selective clock genes among different species.ope

    Utilization of research knowledge in sustainable development pathways: Insights from a transdisciplinary research-for-development programme

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    This study contributes to the ongoing discussion on how to attribute and evaluate the contribution of transdisciplinary research to sustainable development. As co-created knowledge is a key product of transdisciplinary research, we tested the hypothesis that the extent to which this knowledge is utilized beyond the project consortia, in different areas – from scientific methods and insights to policy decisions – and across a continuum of geographical scales can be used to identify potential impact pathways. For this purpose, we developed an analytical framework that links the transdisciplinary process to six possible utilization stages, which we used as indicators of the usability of co-created knowledge. We gathered data from 22 research projects active in 36 countries using a survey and semi-structured interviews. Our results show that even during implementation of the projects, co-created knowledge is utilized by multiple actors at different stages, in all areas and at all scales simultaneously, suggesting multiple impact pathways. Project knowledge is predominantly utilized for national-level policymaking, and research partners named co-creation of knowledge with key stakeholders as the most frequently used mechanism for promoting knowledge utilization. Closer analysis revealed different understandings of and approaches to knowledge co-creation. These can be linked to weaker or stronger definitions of transdisciplinarity. The analysis shows that researchers using strong transdisciplinarity approaches typically face challenges in encompassing multiple epistemologies and facilitating dialogue. Some results suggest that inclusion and collaboration in co-creating knowledge can empower actors otherwise excluded. Our research shows that although transdisciplinary projects have nonlinear impact pathways, these can be partially assessed using the proposed analytical framework. Further, our results indicate a link between usability, inclusion, and collaboration in transdisciplinary research. We conclude with the observation that transdisciplinarity and its requirements still need to be better understood by actors within and beyond the research community
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