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41.
David W. Kikuchi William L. Allen Kevin Arbuckle Thomas G. Aubier Emmanuelle S. Briolat Emily R. Burdfield-Steel Karen L. Cheney Klára Daňková Marianne Elias Liisa Hämäläinen Marie E. Herberstein Thomas J. Hossie Mathieu Joron Krushnamegh Kunte Brian C. Leavell Carita Lindstedt Ugo Lorioux-Chevalier Melanie McClure Callum F. McLellan Iliana Medina Viraj Nawge Erika Páez Arka Pal Stano Pekár Olivier Penacchio Jan Raška Tom Reader Bibiana Rojas Katja H. Rönkä Daniela C. Rößler Candy Rowe Hannah M. Rowland Arlety Roy Kaitlin A. Schaal Thomas N. Sherratt John Skelhorn Hannah R. Smart Ted Stankowich Amanda M. Stefan Kyle Summers Christopher H. Taylor Rose Thorogood Kate Umbers Anne E. Winters Justin Yeager Alice Exnerová 《Journal of evolutionary biology》2023,36(7):975-991
Prey seldom rely on a single type of antipredator defence, often using multiple defences to avoid predation. In many cases, selection in different contexts may favour the evolution of multiple defences in a prey. However, a prey may use multiple defences to protect itself during a single predator encounter. Such “defence portfolios” that defend prey against a single instance of predation are distributed across and within successive stages of the predation sequence (encounter, detection, identification, approach (attack), subjugation and consumption). We contend that at present, our understanding of defence portfolio evolution is incomplete, and seen from the fragmentary perspective of specific sensory systems (e.g., visual) or specific types of defences (especially aposematism). In this review, we aim to build a comprehensive framework for conceptualizing the evolution of multiple prey defences, beginning with hypotheses for the evolution of multiple defences in general, and defence portfolios in particular. We then examine idealized models of resource trade-offs and functional interactions between traits, along with evidence supporting them. We find that defence portfolios are constrained by resource allocation to other aspects of life history, as well as functional incompatibilities between different defences. We also find that selection is likely to favour combinations of defences that have synergistic effects on predator behaviour and prey survival. Next, we examine specific aspects of prey ecology, genetics and development, and predator cognition that modify the predictions of current hypotheses or introduce competing hypotheses. We outline schema for gathering data on the distribution of prey defences across species and geography, determining how multiple defences are produced, and testing the proximate mechanisms by which multiple prey defences impact predator behaviour. Adopting these approaches will strengthen our understanding of multiple defensive strategies. 相似文献
42.
Jérémy Gauthier Joana Meier Fabrice Legeai Melanie McClure Annabel Whibley Anthony Bretaudeau Hélène Boulain Hugues Parrinello Sam T. Mugford Richard Durbin Chenxi Zhou Shane McCarthy Christopher W. Wheat Florence Piron-Prunier Christelle Monsempes Marie-Christine François Paul Jay Camille Noûs Emma Persyn Emmanuelle Jacquin-Joly Camille Meslin Nicolas Montagné Claire Lemaitre Marianne Elias 《Molecular ecology resources》2023,23(4):872-885
The ithomiine butterflies (Nymphalidae: Danainae) represent the largest known radiation of Müllerian mimetic butterflies. They dominate by number the mimetic butterfly communities, which include species such as the iconic neotropical Heliconius genus. Recent studies on the ecology and genetics of speciation in Ithomiini have suggested that sexual pheromones, colour pattern and perhaps hostplant could drive reproductive isolation. However, no reference genome was available for Ithomiini, which has hindered further exploration on the genetic architecture of these candidate traits, and more generally on the genomic patterns of divergence. Here, we generated high-quality, chromosome-scale genome assemblies for two Melinaea species, M. marsaeus and M. menophilus, and a draft genome of the species Ithomia salapia. We obtained genomes with a size ranging from 396 to 503 Mb across the three species and scaffold N50 of 40.5 and 23.2 Mb for the two chromosome-scale assemblies. Using collinearity analyses we identified massive rearrangements between the two closely related Melinaea species. An annotation of transposable elements and gene content was performed, as well as a specialist annotation to target chemosensory genes, which is crucial for host plant detection and mate recognition in mimetic species. A comparative genomic approach revealed independent gene expansions in ithomiines and particularly in gustatory receptor genes. These first three genomes of ithomiine mimetic butterflies constitute a valuable addition and a welcome comparison to existing biological models such as Heliconius, and will enable further understanding of the mechanisms of adaptation in butterflies. 相似文献
43.
Marianne V. Nielsen 《Journal of phycology》1995,31(5):715-719
Light-saturated photosynthesis (Pmax) of Emiliania huxleyi (Lohmann) Hay et Mohler is known to be carbonlimited at natural concentrations of dissolved inorganic carbon (DIC). In the present study, light-limited and light-saturated photosynthetic rates of E. huxleyi were studied at three concentrations of DIC (2.4, 7.4, and 12.4 mM) for high-calcite (Cin/Ctot=0.48) and low-calcite (Cin/Ctot=0.08) cells of the same strain. The photosynthetic efficiency (α) and the maximum quantum yield (θmax)A increased by more than a factor of 2 from the lowest to the highest DIC level. Pmax a, and θmax were always higher for the high-calcite than for the low-calcite cells at identical DIC levels. This may indicate that the calcifcation process acts as an extra supplier of CO2 for photosynthesis making the CO2 shortage at natural DIC levels a little smaller for high-calcite than for low-calcite E. huxleyi. A dependency of θmax on DIC has not previously been shown for marine phytoplankton. θmax is a key parameter in recent biooptical models of phytoplankton productivity, and the results from the present study are therefore important for modeling the productivity of E. huxleyi. 相似文献
44.
Craig J. Coates Catherine L. Turney Marianne Frommer David A. O'Brochta W. D. Warren Peter W. Atkinson 《Molecular & general genetics : MGG》1995,249(2):246-252
Plasmid-based excision assays performed in embryos of two non-drosophilid species using the mariner transposable element from Drosophila mauritiana resulted in empty excision sites identical to those observed after the excision of mariner from D. mauritiana chromosomes. In the presence of the autonomous mariner element Mos1, excision products were recovered from D. melanogaster, D. mauritiana and the blowfly Lucilia cuprina. When a hsp82 heat shock promoter-Mos1 construct was used to supply mariner transposase, excision products were also recovered from the Queensland fruitfly Bactrocera tryoni. Analysis of DNA sequences at empty excision sites led us to hypothesise that the mariner excision/repair process involves the formation of a heteroduplex at the excision breakpoint. The success of these assays suggests that they will provide a valuable tool for assessing the ability of mariner and mariner-like elements to function in non-drosophilid insects and for investigating the basic mechanisms of mariner excision and repair. 相似文献
45.
During the production by mammalian cells of recombinant factor VIII from which the B domain was deleted (rFVIII), proteolytic
cleavages in the C-terminal part of the heavy chain were observed (Kjalke et al., 1995). By radioactive pulse labelling it
was investigated whether the cleavages took place inside the cells during protein synthesis or after release in the medium.
The rFVIII-producing CHO (Chinese hamster ovary) cells were cultured in the presence of 35S-methionine and then the cell lysate and the conditioned media were immunoprecipitated and analyzed by electrophoresis. By
pulse labelling and chasing for various time periods, it was shown that the cleavages only took place after secretion of the
protein from the cells. Adding cell lysate to uncleaved rFVIII caused cleavage of the heavy chain, as seen by loss of binding
to a monoclonal antibody specific for intact rFVIII, indicating that the cleavage was performed by proteinase(s) released
from the lysed cells. By incubating intact rFVIII with the multicatalytic proteinase (proteasome) present in cytoplasm and
nucleus of eukaryotic cells, loss of binding to the monoclonal antibody was observed. This indicates that the multicatalytic
proteinase, released from lysed rFVIII producing cells, could be responsible for the cleavage of rFVIII. Among several protease
inhibitors tested, only bacitracin was found to diminish the extent of cleavage. Phosphatidylserine also protected rFVIII
against cleavage, probably by binding to rFVIII.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
46.
The 5-HT (serotonin) distribution in the nervous system of the macrodasyoid gastrotrich Turbanella cornuta was studied using immunocytochemical methods. Positive immunoreaction was found in two pairs of neurons. The neurons of one pair had processes which extended peripherally to the surface of the body. Central processes of both pairs entered the brain commissure and proceeded into the longitudinal cords. Unlike other acoelomate worms studied so far, the Platyhelminthes and the Nematoda, in this gastrotrich no 5-HT positive perikarya or processes were present in the pharynx innervation, and no positive neurons sent processes directly to the nerve cords 相似文献
47.
Seven New Mutations in hMSH2, an HNPCC Gene, Identified by Denaturing Gradient-Gel Electrophoresis 总被引:21,自引:3,他引:18 下载免费PDF全文
Juul Wijnen Hans Vasen P. Meera Khan Fred H. Menko Heleen van der Klift Claus van Leeuwen Marianne van den Broek Inge van Leeuwen-Cornelisse Fokko Nagengast Anne Meijers-Heijboer Dick Lindhout Gerrit Griffioen Annemieke Cats Jan Kleibeuker Liliana Varesco Lucio Bertario Marie Luise Bisgaard Jan Mohr Riccardo Fodde 《American journal of human genetics》1995,56(5):1060-1066
Hereditary nonpolyposis colorectal cancer (HNPCC) is a relatively common autosomal dominant cancer-susceptibility condition. The recent isolation of the DNA mismatch repair genes (hMSH2, hMLH1, hPMS1, and hPMS2) responsible for HNPCC has allowed the search for germ-line mutations in affected individuals. In this study we used denaturing gradient-gel electrophoresis to screen for mutations in the hMSH2 gene. Analysis of all the 16 exons of hMSH2, in 34 unrelated HNPCC kindreds, has revealed seven novel pathogenic germ-line mutations resulting in stop codons either directly or through frameshifts. Additionally, nucleotide substitutions giving rise to one missense, two silent, and one useful polymorphism have been identified. The proportion of families in which hMSH2 mutations were found is 21%. Although the spectrum of mutations spread at the hMSH2 gene among HNPCC patients appears extremely heterogeneous, we were not able to establish any correlation between the site of the individual mutations and the corresponding tumor spectrum. Our results indicate that, given the genomic size and organization of the hMSH2 gene and the heterogeneity of its mutation spectrum, a rapid and efficient mutation detection procedure is necessary for routine molecular diagnosis and presymptomatic detection of the disease in a clinical setup. 相似文献
48.
Marianne Borloo Koen Augustyns Alexander Belyaev Ingrid de Meester Anne-Marie Lambeir Filip Goossens Willy Bollaert Padinchare Rajan Simon Scharpé Achiel Haemers 《Letters in Peptide Science》1995,2(3-4):198-202
Summary A series of azaproline dipeptides with various N-substituents were synthesized as possible active-site-directed inhibitors of two proline-specific serine proteases, dipeptidyl peptidase IV and prolyl oligopeptidase. Compounds with semicarbazide, carbazate, acylhydrazine and sulphonylhydrazine structures were tested. Some compounds show moderate activity, i.e., in the millimolar range. 相似文献
49.
André W. Schram Marianne Dreissen Johan Bastiaannet Wilma E. Donker-Koopman Elisabeth M. Brouwer-Kelder Gabriele Weitz John A. Barranger Konrad Sandhoff Joseph M. Tager 《Bioscience reports》1984,4(12):1051-1057
The immunoblotting technique was used to identify sphingomyeJinase protein in samples of tissue and urine after subjection to poIyacrylamide-gel etectrophoresis in the presence of sodium dodecyl sulphate. In a sphingomyelinase preparation purified from control urine a prominent band was seen with an Mr of 28 000 Da. Glycoprotein fractions from urine and placenta, a membrane extract from spleen, and a partially purified sphingomyelinase preparation from placenta contained the 28 000-Da band plus additional, higher-Mr bands. The 28 000-Da band was detectable in urine from a patient with Niemann-Pick disease type C, but not in urine from patients with Niemann-Pick disease types A and B. It is concluded t h a t sphingomyeJinase is composed of at least one polypeptide with an Mr of 28 000 Da and that this polypeptide is deficient in the urine of patients with Niemann-Pick disease types A and B. 相似文献
50.
Summary Experiments were performed to investigate growth, ethanol and glycerol production by wild-type strains (RHO) and respiratory-deficient (rho) mutants of Saccharomyces cerevisiae. Furthermore protoplasts were fused in order to enhance the fermentation capacity of a flocculent strain. At high substrate conditions, 150 g/l of saccharose, there is no difference in cell growth. However, at a glucose concentration of 10–20 g/l the mutants grow much slower. After 3 days of incubation at 28° C in a complete medium the viability of the two strains is the same. In minimal medium on the other hand the number of viable cells of the mutant is 100-fold reduced. All mutants tested showed a higher specific activity of alcohol dehydrogenase (ADH I) and an enhanced production of glycerol compared with the wild-type strain. By protoplast fusion a modified flocculent strain was obtained with higher specific activity of ADH I and a reduced biosynthesis of glycerol. However, the yields of ethanol (75–78%) are about the same for the wild-type strain and the rho mutants under aerobic conditions in absence of catabolite repression. 相似文献