Current biology : CB最新文献

{"title":"Floral Pigmentation Has Responded Rapidly to Global Change in Ozone and Temperature.","authors":"Matthew H Koski,&nbsp;Drew MacQueen,&nbsp;Tia-Lynn Ashman","doi":"10.1016/j.cub.2020.08.077","DOIUrl":"https://doi.org/10.1016/j.cub.2020.08.077","url":null,"abstract":"<p><p>Across kingdoms, organisms ameliorate UV stress by increasing UV-absorbing pigmentation. Rapid ozone degradation during the 20^th century resulted in elevated UV incidence, but pigmentation responses to this aspect of global change have yet to be demonstrated. In flowering plants, UV exposure favors larger areas of UV-absorbing pigmentation on petals, which protects pollen from UV-damage. Pigmentation also affects floral thermoregulation, suggesting climate warming may additionally impact pigmentation. We used 1,238 herbarium specimens collected from 1941 to 2017 to test whether change in UV floral pigmentation was associated with altered ozone and temperature in 42 species spanning three continents. We tested three predictions: first, UV-absorbing pigmentation will increase temporally and be correlated with reduced ozone (higher UV) when accounting for effects of temperature; second, taxa that experienced larger ozone declines will display larger increases in pigmentation; and third, taxa with anthers exposed to ambient UV will respond more strongly than those with anthers protected by petals. Globally, the extent of petal UV pigmentation increased significantly across taxa by ∼2% per year. However, temporal change was species specific-increasing in some taxa but declining in others. Species with exposed anthers experiencing larger declines in ozone displayed more dramatic pigmentation increases. For taxa with anthers enclosed within petals, pigmentation declined with increases in temperature, supporting a thermoregulatory role of UV pigmentation. Results document a rapid phenotypic response of floral pigmentation to anthropogenic climatic change, suggesting that global change may alter pollination through its impact on floral color, with repercussions for plant reproductive fitness.</p>","PeriodicalId":505214,"journal":{"name":"Current biology : CB","volume":" ","pages":"4425-4431.e3"},"PeriodicalIF":9.2,"publicationDate":"2020-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.cub.2020.08.077","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38396932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stress and life history.","authors":"Pat Monaghan,&nbsp;Karen A Spencer","doi":"10.1016/j.cub.2014.04.017","DOIUrl":"https://doi.org/10.1016/j.cub.2014.04.017","url":null,"abstract":"<p><p>In his book on behavioural endocrinology, Randy Nelson describes 'stress' as a 'notoriously ethereal concept'. Yet, despite this lack of clarity, studies of the consequences of stress across different time scales, life history stages, taxa and levels of biological enquiry form a large part of modern biology and biomedicine. Organisms need to recognise and respond to environmental challenges. Being able to do so appropriately, and with minimal costs, is an important physiological attribute, with great adaptive value. The costs and benefits of different mechanisms that enable organisms to cope with unpredictable environmental changes can be manifest to different degrees at different life stages. Accordingly, the level of stress experienced in the environment can act as a strong selective pressure that drives the evolution of life histories. </p>","PeriodicalId":505214,"journal":{"name":"Current biology : CB","volume":" ","pages":"R408-12"},"PeriodicalIF":9.2,"publicationDate":"2014-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.cub.2014.04.017","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"32355066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Specialization of mutualistic interaction networks decreases toward tropical latitudes.","authors":"Matthias Schleuning,&nbsp;Jochen Fründ,&nbsp;Alexandra-Maria Klein,&nbsp;Stefan Abrahamczyk,&nbsp;Ruben Alarcón,&nbsp;Matthias Albrecht,&nbsp;Georg K S Andersson,&nbsp;Simone Bazarian,&nbsp;Katrin Böhning-Gaese,&nbsp;Riccardo Bommarco,&nbsp;Bo Dalsgaard,&nbsp;D Matthias Dehling,&nbsp;Ariella Gotlieb,&nbsp;Melanie Hagen,&nbsp;Thomas Hickler,&nbsp;Andrea Holzschuh,&nbsp;Christopher N Kaiser-Bunbury,&nbsp;Holger Kreft,&nbsp;Rebecca J Morris,&nbsp;Brody Sandel,&nbsp;William J Sutherland,&nbsp;Jens-Christian Svenning,&nbsp;Teja Tscharntke,&nbsp;Stella Watts,&nbsp;Christiane N Weiner,&nbsp;Michael Werner,&nbsp;Neal M Williams,&nbsp;Camilla Winqvist,&nbsp;Carsten F Dormann,&nbsp;Nico Blüthgen","doi":"10.1016/j.cub.2012.08.015","DOIUrl":"https://doi.org/10.1016/j.cub.2012.08.015","url":null,"abstract":"<p><p>Species-rich tropical communities are expected to be more specialized than their temperate counterparts. Several studies have reported increasing biotic specialization toward the tropics, whereas others have not found latitudinal trends once accounting for sampling bias or differences in plant diversity. Thus, the direction of the latitudinal specialization gradient remains contentious. With an unprecedented global data set, we investigated how biotic specialization between plants and animal pollinators or seed dispersers is associated with latitude, past and contemporary climate, and plant diversity. We show that in contrast to expectation, biotic specialization of mutualistic networks is significantly lower at tropical than at temperate latitudes. Specialization was more closely related to contemporary climate than to past climate stability, suggesting that current conditions have a stronger effect on biotic specialization than historical community stability. Biotic specialization decreased with increasing local and regional plant diversity. This suggests that high specialization of mutualistic interactions is a response of pollinators and seed dispersers to low plant diversity. This could explain why the latitudinal specialization gradient is reversed relative to the latitudinal diversity gradient. Low mutualistic network specialization in the tropics suggests higher tolerance against extinctions in tropical than in temperate communities.</p>","PeriodicalId":505214,"journal":{"name":"Current biology : CB","volume":" ","pages":"1925-31"},"PeriodicalIF":9.2,"publicationDate":"2012-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.cub.2012.08.015","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30907924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Axon regrowth during development and regeneration following injury share molecular mechanisms.","authors":"Shiri P Yaniv,&nbsp;Noa Issman-Zecharya,&nbsp;Meital Oren-Suissa,&nbsp;Benjamin Podbilewicz,&nbsp;Oren Schuldiner","doi":"10.1016/j.cub.2012.07.044","DOIUrl":"https://doi.org/10.1016/j.cub.2012.07.044","url":null,"abstract":"<p><strong>Background: </strong>The molecular mechanisms that determine axonal growth potential are poorly understood. Intrinsic growth potential decreases with age, and thus one strategy to identify molecular pathways controlling intrinsic growth potential is by studying developing young neurons. The programmed and stereotypic remodeling of Drosophila mushroom body (MB) neurons during metamorphosis offers a unique opportunity to uncover such mechanisms. Despite emerging insights into MB γ-neuron axon pruning, nothing is known about the ensuing axon re-extension.</p><p><strong>Results: </strong>Using mosaic loss of function, we found that the nuclear receptor UNF (Nr2e3) is cell autonomously required for the re-extension of MB γ-axons following pruning, but not for the initial growth or guidance of any MB neuron type. We found that UNF promotes this process of developmental axon regrowth via the TOR pathway as well as a late axon guidance program via an unknown mechanism. We have thus uncovered a novel developmental program of axon regrowth that is cell autonomously regulated by the UNF nuclear receptor and the TOR pathway.</p><p><strong>Conclusions: </strong>Our results suggest that UNF activates neuronal re-extension during development. Taken together, we show that axon growth during developmental remodeling is mechanistically distinct from initial axon outgrowth. Due to the involvement of the TOR pathway in axon regeneration following injury, our results also suggests that developmental regrowth shares common molecular mechanisms with regeneration following injury.</p>","PeriodicalId":505214,"journal":{"name":"Current biology : CB","volume":" ","pages":"1774-82"},"PeriodicalIF":9.2,"publicationDate":"2012-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.cub.2012.07.044","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30857626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rab32 regulates melanosome transport in Xenopus melanophores by protein kinase a recruitment.","authors":"Minjong Park, Anna S Serpinskaya, Nancy Papalopulu, Vladimir I Gelfand","doi":"10.1016/j.cub.2007.10.051","DOIUrl":"10.1016/j.cub.2007.10.051","url":null,"abstract":"<p><p>Intracellular transport is essential for cytoplasm organization, but mechanisms regulating transport are mostly unknown. In Xenopus melanophores, melanosome transport is regulated by cAMP-dependent protein kinase A (PKA). Melanosome aggregation is triggered by melatonin, whereas dispersion is induced by melanocyte-stimulating hormone (MSH). The action of hormones is mediated by cAMP: High cAMP in MSH-treated cells stimulates PKA, whereas low cAMP in melatonin-treated cells inhibits it. PKA activity is typically restricted to specific cell compartments by A-kinase anchoring proteins (AKAPs). Recently, Rab32 has been implicated in protein trafficking to melanosomes and shown to function as an AKAP on mitochondria. Here, we tested the hypothesis that Rab32 is involved in regulation of melanosome transport by PKA. We demonstrated that Rab32 is localized to the surface of melanosomes in a GTP-dependent manner and binds to the regulatory subunit RIIalpha of PKA. Both RIIalpha and Cbeta subunits of PKA are required for transport regulation and are recruited to melanosomes by Rab32. Overexpression of wild-type Rab32, but not mutants unable to bind PKA or melanosomes, inhibits melanosome aggregation by melatonin. Therefore, in melanophores, Rab32 is a melanosome-specific AKAP that is essential for regulation of melanosome transport.</p>","PeriodicalId":505214,"journal":{"name":"Current biology : CB","volume":" ","pages":"2030-4"},"PeriodicalIF":0.0,"publicationDate":"2007-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2330279/pdf/nihms35604.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41027018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}