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91.
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
92.
Viviane Fátima de Oliveira Lucas Figueiredo Gabriel de Oliveira Correia Maria de Fátima Pires da Silva Machado Hugo Zeni Neto Wanderley Dantas dos Santos Claudete Aparecida Mangolin 《Global Change Biology Bioenergy》2023,15(12):1465-1476
The burgeoning cellulosic ethanol industry necessitates advancements in enzymatic saccharification, effective pretreatments for lignin removal, and the cultivation of crops more amenable to saccharification. Studies have demonstrated that natural inhibitors of lignin biosynthesis can enhance the saccharification of lignocellulose, even in tissues generated several months post-treatment. In this study, we applied daidzin (a competitive inhibitor of coniferaldehyde dehydrogenase), piperonylic acid (a quasi-irreversible inhibitor of cinnamate 4-hydroxylase), and methylenedioxy cinnamic acid (a competitive inhibitor of 4-coenzyme A ligase) to 60-day-old crops of two conventional Brazilian sugarcane cultivars and two energy cane clones, bred specifically for enhanced biomass production. The resultant biomasses were evaluated for lignin content and enzymatic saccharification efficiency without additional lignin-removal pretreatments. The treatments amplified the production of fermentable sugars in both the sugarcane cultivars and energy cane clones. The most successful results softened the most recalcitrant lignocellulose to the level of the least recalcitrant of the biomasses tested. Interestingly, the softest material became even more susceptible to saccharification. 相似文献
93.
Metabolic scope and its utilization in relation to feeding and activity were measured in individual and grouped zebrafish (weight range, 430–551 mg) at 24° C by respirometry. Mean maximum metabolic rate, induced by swimming to exhaustion, Rmax(i), was 1223 (s.d. , 157) mg O2, kg?1 h?1 for individuals. Standard metabolic rate, Rs. was 364 mg O2 kg?1 h?1, as estimated by extrapolating to zero activity from measurements of unfed, spontaneously active individuals. Mean routine metabolic rate, Rrout, of individuals was 421 (s.d. , 58) mg O2, kg-1 h-1. The mean voluntary maximum metabolic rate, Rmax(v), following transfer of minimally exercised fish to the respirometer, was 1110 (s.d. , 83) mg O2 kg ?1 h?1 for groups of six fish, and was not significantly different from the value measured for individuals, 1066 (s.d. , 122) mg O2, kg?1 h?1. Grouped fish acclimated to the respirometer more slowly than individual fish and exhibited significantly higher Rrout, apparently a result of greater social interaction and activity in groups. Mean Rrout for groups was 560 (s.d. , 78) mg O2, kg?1 h?1. While groups of zebrafish fed a ration of 5% wet body weight day?1 exhibited consistently higher metabolic rates than fish fed rations of 2.5% wet body weight day?1 the high ration group still used only a maximum of 77% of the metabolic scope. Zebrafish of the size studied do not appear to demonstrate a high degree of conflict in utilization of metabolic scope by different respiratory components. The metabolic rates measured for zebrafish are among the highest yet measured for fish of similar size and at similar temperatures. 相似文献
94.
Two closely related, photosynthetic species belonging to the genus Dinophysis were examined, D. acuminata Claparède et Lachmann and D. fortii Pavillard. Typical dinoflagellate features include the amphiesmal covering enclosing the cells and the structure of the nucleus and mitochondria. Many other characteristics seem to be specific to the order Dinophysiales. Many rhabdosomes are present, and complex mucocysts are found beneath the amphiesma. The thecal pores are unusual with the base of the pore occluded by a thin disc that is continuous with the main amphiesmal plate. The structure of the apical pore is also distinctive. Chloroplasts are grouped together in chromatospheres, enclosed by a double membrane, and contain paired thylakoids with electron dense contents in the lumen. The two pusules are extensive, each branching off the flagellar canal, and consisting of a large antechamber and a number of convoluted sacs. The entrance of each antechamber, and site of an emerging flagellum, is surrounded by a striated fibrous collar. Near the flagellar pore is a prominent microtubular/microbody complex which penetrates deep into the cell cytoplasm. Consideration is given to taxonomic position of the Dinophysiales and also to the nature and origins of the chloroplasts. 相似文献
95.
P. Fleurat-Lessard S. Bouché-Pillon C. Leloup W. J. Lucas R. Serrano J. -L. Bonnemain 《Protoplasma》1995,188(3-4):180-185
Summary Immunocytochemical techniques were employed to study the spatial distribution of the plasma membrane H+-ATPase within various cell types of the young reactive primary pulvinus ofMimosa pudica L. These cells were interconnected by large numbers of plasmodesmata, being concentrated within pit-fields. Although we could routinely detect evidence of the H+-ATPase along the plasma membrane, immunolabelling was rarely, if ever, observed along the plasma membranes of the plasmodesmata. This finding is discussed with respect to the likely specialized supramolecular structure of the plasmodesma.Abbreviations SEL
size exclusion limit of plasmodesmata 相似文献
96.
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
97.
Hepatic nuclear factor 3- and hormone-regulated expression of the phosphoenolpyruvate carboxykinase and insulin-like growth factor-binding protein 1 genes. 总被引:11,自引:4,他引:7 下载免费PDF全文
98.
Preparations by the high dilution method are reported for seven macrocyclic thioether-esters and thioether-thioesters (L1–;L7). Yields in these reactions between thiodiglycolyl dichloride and appropriate ,ω-diols or dithiols range from 10 to 51%. The compounds are characterized by 1H and 13C NMR, IR and high resolution mass spectroscopy. They react with salts of Pd(II), Pt(II) and Ag(I) to form complexes of which MX2·L2, (M = Pt, X = Cl; M = Pd, X = Cl, Br, I, SCN), [Pd(L2)2][CF3SO3]2·H2O and [Ag(L5)2][CF3SO3]·C2H5OH have been isolated and characterized by elemental analysis, IR and NMR spectroscopy. NMR spectra indicate reversible dissociation of the ligand occurs in dimethyl sulfoxide solvent for PdCl2·L2 but not for the Pt analogue. For PtCl2·L2, spectra indicate that the ligand is undergoing a conformational ‘wag’ about its pair of equivalent sulfurs. These remain bound to the metal while the unique sulfur moves from the apical position of the coordination sphere to a non-coordinated situation. Simultaneously, inversions at the bound sulfurs are occurring. 相似文献
99.
Sergio Vidal Matilde Lombardero Pablo Sánchez Albina Román Lucas Moya 《The Histochemical journal》1995,27(3):204-209
Summary A simple procedure is described for removing Epon resin from semi-thin 1 m sections, which permits excellent postembedding immunohistochemical staining (avidin-biotin complex technique). The procedure was developed for the detection of growth hormone and prolactin in bovine adenohypophysis fixed with 2% paraformaldehyde and 0.5% glutaraldehyde in 0.1 m sodium cacodylate buffer pH 7.4–7.6. The results indicate that the removal of the epoxy embedding medium prior to the application of the immunohistochemical reagents was essential for the successful localization of the antigenic determinants of the two hormones. The immunocytochemical reactivity was obtained only after treating the sections with a solution of potassium hydroxide in a mixture of absolute methyl alcohol and propylene oxide (Maxwell's solution). An enhanced immunoreactivity was obtained when this treatment was followed by an additional treatment with either 4% hydrogen peroxide or a saturated aqueous solution of sodium metaperiodate. Because of the easy preparation of the Epon removal solution and the good structural preservation without damage to the antigenic determinants, Maxwell's solution is suggested as a good etching agent which can be used in immunohistochemical studies on semi-thin sections with excellent results. 相似文献
100.
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