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In species-poor communities, genetic diversity potentially plays an important role for ecosystem functioning, though this is still largely unexplored in marine and estuarine ecosystems. We studied how genetic diversity (sensu genotypic diversity and/or allelic richness) affects ecosystem functioning in marine habitat-forming plant communities. First, we conducted a 15-month field experiment in the highly seasonal Baltic Sea and established mono- and polycultures of different genotypes and genotype combinations of Zostera marina. Second, we reviewed existing literature and performed a meta-analysis of 12 studies including this study. We found no evidence of positive genetic diversity effects on shoot production in the field experiment, but diversity enhanced community stability over time. The literature review revealed that a majority of the included studies observed positive effects of genetic diversity on ecosystem functions such as primary production and nutrient uptake. The results from the meta-analysis support the hypothesis that genetic diversity effects on productivity are stronger during or after periods of stress. These diversity effects were also more positive in the field compared to mesocosm studies. Our results indicate that genetic diversity has positive effects on ecosystem functioning, particularly during increased environmental stress. Thus, local genetic diversity should be preserved especially in species-poor ecosystems, where it potentially provides insurance against environmental change. 相似文献
43.
Camilla Ru Rasmussen Anne Nygaard Weisbach Kristian Thorup-Kristensen Jacob Weiner 《Journal of Plant Ecology》2019,12(1):78
Aims
There is much evidence that plant competition below ground is size symmetric, i.e. that competing plants share contested resources in proportion to their sizes. Several researchers have hypothesized that a patchy distribution of soil nutrients could result in size-asymmetric root competition. We tested this hypothesis. 相似文献
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Mechanisms regulating sexual differentiation of the zebra finch song system are not well understood. The present study was designed to more fully characterize secretory carrier membrane protein 1 (SCAMP1), which was identified in a cDNA microarray screen as showing increased expression in the forebrains of developing male compared with female zebra finches. We completed the sequence of the open reading frame and used in situ hybridization to compare mRNA in song control regions of juvenile (25-day-old) individuals. Expression was significantly greater in the HVC (used as a proper name) and robust nucleus of the arcopallium (RA) in males than in females. Immunohistochemistry revealed that SCAMP1 protein is also expressed in these two brain regions, and qualitatively appears greater in males. Western analysis confirmed that the protein is increased in the telencephalon of males when compared with females at 25 days of age. These results are consistent with the idea that SCAMP1 is involved in masculinization of these brain areas, perhaps facilitating the survival of cells within them. 相似文献
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Roveta Camilla Annibaldi Anna Domenichelli Federico Gregorin Chiara Gridelli Stefano Pantano Valentina Vagnoni Flavio Puce Stefania 《Aquatic Ecology》2022,56(3):631-637
Aquatic Ecology - Jellyfish blooms are an increasingly common event in our seas. Occurring via polyps’ asexual reproduction induced by human stresses, they represent a hazard for ecosystems... 相似文献
48.
Alptekin Burcu Erfatpour Mohammad Mangel Dylan Pauli Duke Blake Tom Turner Hannah Lachowiec Jennifer Sherman Jamie Fischer Andreas 《Molecular breeding : new strategies in plant improvement》2022,42(10):1-15
Molecular Breeding - Maize amylose is a type of high value-added starch used for medical, food, and chemical applications. Mutations in the starch branching enzyme (SBEIIb), with recessive ae... 相似文献
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Francesca Chiarini Francesca Paganelli Tommaso Balestra Cristina Capanni Antonietta Fazio Maria Cristina Manara Lorena Landuzzi Stefania Petrini Camilla Evangelisti Pier-Luigi Lollini Alberto M. Martelli Giovanna Lattanzi Katia Scotlandi 《Cell death & disease》2022,13(4)
Lamin A, a main constituent of the nuclear lamina, is involved in mechanosignaling and cell migration through dynamic interactions with the LINC complex, formed by the nuclear envelope proteins SUN1, SUN2 and the nesprins. Here, we investigated lamin A role in Ewing Sarcoma (EWS), an aggressive bone tumor affecting children and young adults. In patients affected by EWS, we found a significant inverse correlation between LMNA gene expression and tumor aggressiveness. Accordingly, in experimental in vitro models, low lamin A expression correlated with enhanced cell migration and invasiveness and, in vivo, with an increased metastatic load. At the molecular level, this condition was linked to altered expression and anchorage of nuclear envelope proteins and increased nuclear retention of YAP/TAZ, a mechanosignaling effector. Conversely, overexpression of lamin A rescued LINC complex organization, thus reducing YAP/TAZ nuclear recruitment and preventing cell invasiveness. These effects were also obtained through modulation of lamin A maturation by a statin-based pharmacological treatment that further elicited a more differentiated phenotype in EWS cells. These results demonstrate that drugs inducing nuclear envelope remodeling could be exploited to improve therapeutic strategies for EWS.Subject terms: Nuclear organization, Cancer 相似文献
50.
Lovisa Nilsson Camilla Olsson Johan Elmberg Nils Bunnefeld Niklas Liljebck Johan Mnsson 《Ecology and evolution》2022,12(3)
Knowledge about intraspecific and individual variation in bird migration behavior is important to predict spatiotemporal distribution, patterns of phenology, breeding success, and interactions with the surrounding environment (e.g., human livelihoods). Such variation is key to adaptive, evolutionary responses, i.e., how individuals respond spatiotemporally to the environment to maximize fitness. In this study we used GPS location data from one to three full annual cycles from 76 Greylag geese (Anser anser) to test the hypothesis that geese originating at five latitudinally separated capture sites in Sweden have different migration strategies. We also assessed individual consistency in movement strategy over consecutive annual cycles. We used the scale‐independent net squared displacement modeling framework to quantify variables of autumn and spring migration for geese from each capture site: distance, timing, and duration. Our results demonstrate a positive correlation between migration distance and latitudinal origin. Geese from the northernmost site on average migrated farther south and about 15 times as far as the short‐moving or resident geese from the two southernmost sites. Movement strategies of individual geese varied considerably both within and among capture sites. Individual consistency in movement strategy from one annual cycle to the consecutive was high in geese from the northern sites moving the farthest, whereas the resident or short‐moving geese from the southernmost sites generally showed lower or no individual consistency. These changes have come about during a time span so short (i.e., ca. 35 years or 8–10 generations) that it can unlikely be explained by classical Darwinian between‐generation adaptation. Consequently, and given that young geese follow their parents during their first migration, we presume an important role of within‐family, inter‐generation change as a driver behind the large‐scale changed migration habits in Swedish Greylag geese. 相似文献