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排序方式: 共有101条查询结果,搜索用时 15 毫秒
1.
G. HOLSBEEK J. MERGEAY H. HOTZ J. PLÖTNER F. A. M. VOLCKAERT L. DE MEESTER 《Molecular ecology》2008,17(23):5023-5035
In Western Europe, many pond owners introduce amphibians for ornamental purposes. Although indigenous amphibians are legally protected in most European countries, retailers are circumventing national and international legislation by selling exotic nonprotected sibling species. We investigated to what extent non‐native species of the European water frog complex (genus Pelophylax) have become established in Belgium, using morphological, mitochondrial and nuclear genetic markers. A survey of 87 sampling sites showed the presence of non‐native water frogs at 47 locations, mostly Marsh frogs (Pelophylax ridibundus). Surprisingly, at least 19% of all these locations also harboured individuals with mitochondrial haplotypes characteristic of Anatolian water frogs (Pelophylax cf. bedriagae). Nuclear genotyping indicated widespread hybridization and introgression between P. ridibundus and P. cf. bedriagae. In addition, water frogs of Turkish origin obtained through a licensed retailer, also contained P. ridibundus and P. cf. bedriagae, with identical haplotypes to the wild Belgian populations. Although P. ridibundus might have invaded Belgium by natural range expansion from neighbouring countries, our results suggest that its invasion was at least partly enhanced by commercial trade, with origins as far as the Middle East. Also the invasion and rapid spread of Anatolian lineages, masked by their high morphological similarity to P. ridibundus, is likely the result of unregulated commercial trade. We expect that Anatolian frogs will further invade the exotic as well as the native range of P. ridibundus and other Pelophylax species elsewhere in Western and Central Europe, with risks of large‐scale hybridization and introgression. 相似文献
2.
Antony?P?Martin William?M?Palmer Caitlin?S?Byrt Robert?T?Furbank Christopher?PL?GrofEmail author 《Biotechnology for biofuels》2013,6(1):186
Background
A major hindrance to the development of high yielding biofuel feedstocks is the ability to rapidly assess large populations for fermentable sugar yields. Whilst recent advances have outlined methods for the rapid assessment of biomass saccharification efficiency, none take into account the total biomass, or the soluble sugar fraction of the plant. Here we present a holistic high-throughput methodology for assessing sweet Sorghum bicolor feedstocks at 10 days post-anthesis for total fermentable sugar yields including stalk biomass, soluble sugar concentrations, and cell wall saccharification efficiency.Results
A mathematical method for assessing whole S. bicolor stalks using the fourth internode from the base of the plant proved to be an effective high-throughput strategy for assessing stalk biomass, soluble sugar concentrations, and cell wall composition and allowed calculation of total stalk fermentable sugars. A high-throughput method for measuring soluble sucrose, glucose, and fructose using partial least squares (PLS) modelling of juice Fourier transform infrared (FTIR) spectra was developed. The PLS prediction was shown to be highly accurate with each sugar attaining a coefficient of determination (R 2 ) of 0.99 with a root mean squared error of prediction (RMSEP) of 11.93, 5.52, and 3.23 mM for sucrose, glucose, and fructose, respectively, which constitutes an error of <4% in each case. The sugar PLS model correlated well with gas chromatography–mass spectrometry (GC-MS) and brix measures. Similarly, a high-throughput method for predicting enzymatic cell wall digestibility using PLS modelling of FTIR spectra obtained from S. bicolor bagasse was developed. The PLS prediction was shown to be accurate with an R 2 of 0.94 and RMSEP of 0.64 μg.mgDW-1.h-1.Conclusions
This methodology has been demonstrated as an efficient and effective way to screen large biofuel feedstock populations for biomass, soluble sugar concentrations, and cell wall digestibility simultaneously allowing a total fermentable yield calculation. It unifies and simplifies previous screening methodologies to produce a holistic assessment of biofuel feedstock potential.3.
GUSTAVO BRUGES ADOLFO BORGES SINAI SÁNCHEZ DE VILLARROEL ITALA LIPPO DE BÉCEMBERG GISELA FRANCIS DE TOBA FABIOLA PLÁCERES 《Journal of receptor and signal transduction research》2013,33(2-3):189-216
Muscarinic activation of tracheal smooth muscle (TSM) involves a M3AChR/heterotrimeric-G protein/NPR-GC coupling mechanism. G protein activators Mastoparan (MAS) and Mastoparan-7 stimulated 4- and 10-fold the NPR-GC respectively, being insensitive to PTX and antibodies against Gαi/o subfamily. Muscarinic and MAS stimulation of NPR-GC was blocked by antibodies against C-terminal of Gαq16, whose expression was confirmed by RT-PCR. However, synthetic peptides from C-terminal of Gαq15/16 stimulated the NPR-GC. Coupling of αq16 to M3AChR is supported by MAS decreased [3H]QNB binding, being abolished after M3AChR-4-DAMP-alkylation. Anti-i3M3AChR antibodies blocked the muscarinic activation of NPR-GC, and synthetic peptide from i3M3AChR (M3P) was more potent than MAS increasing GTPγ [35S] and decreasing the [3H]QNB activities. Coupling between NPR-GC and Gαq16 was evaluated by using trypsin-solubilized-fraction from TSM membranes, which displayed a MAS-sensitive-NPR-GC activity, being immunoprecipitated with anti-Gαq16, also showing an immunoreactive heterotrimeric-G-β -subunit. These data support the existence of a novel transducing cascade, involving Gαq16β γ coupling M3AChR to NPR-GC. 相似文献
4.
5.
Nicolas Bloemeke Kevin MeighenBerger Manuel Hitzenberger Nina C Bach Marina Parr Joao PL Coelho Dmitrij Frishman Martin Zacharias Stephan A Sieber Matthias J Feige 《The EMBO journal》2022,41(24)
One‐third of the human proteome is comprised of membrane proteins, which are particularly vulnerable to misfolding and often require folding assistance by molecular chaperones. Calnexin (CNX), which engages client proteins via its sugar‐binding lectin domain, is one of the most abundant ER chaperones, and plays an important role in membrane protein biogenesis. Based on mass spectrometric analyses, we here show that calnexin interacts with a large number of nonglycosylated membrane proteins, indicative of additional nonlectin binding modes. We find that calnexin preferentially bind misfolded membrane proteins and that it uses its single transmembrane domain (TMD) for client recognition. Combining experimental and computational approaches, we systematically dissect signatures for intramembrane client recognition by calnexin, and identify sequence motifs within the calnexin TMD region that mediate client binding. Building on this, we show that intramembrane client binding potentiates the chaperone functions of calnexin. Together, these data reveal a widespread role of calnexin client recognition in the lipid bilayer, which synergizes with its established lectin‐based substrate binding. Molecular chaperones thus can combine different interaction modes to support the biogenesis of the diverse eukaryotic membrane proteome. 相似文献
6.
7.
Chen XM O'Hara SP Nelson JB Splinter PL Small AJ Tietz PS Limper AH LaRusso NF 《Journal of immunology (Baltimore, Md. : 1950)》2005,175(11):7447-7456
Infection of epithelial cells by Cryptosporidium parvum triggers a variety of host-cell innate and adaptive immune responses including release of cytokines/chemokines and up-regulation of antimicrobial peptides. The mechanisms that trigger these host-cell responses are unclear. Thus, we evaluated the role of TLRs in host-cell responses during C. parvum infection of cultured human biliary epithelia (i.e., cholangiocytes). We found that normal human cholangiocytes express all known TLRs. C. parvum infection of cultured cholangiocytes induces the selective recruitment of TLR2 and TLR4 to the infection sites. Activation of several downstream effectors of TLRs including IL-1R-associated kinase, p-38, and NF-kappaB was detected in infected cells. Transfection of cholangiocytes with dominant-negative mutants of TLR2 and TLR4, as well as the adaptor molecule myeloid differentiation protein 88 (MyD88), inhibited C. parvum-induced activation of IL-1R-associated kinase, p-38, and NF-kappaB. Short-interfering RNA to TLR2, TLR4, and MyD88 also blocked C. parvum-induced NF-kappaB activation. Moreover, C. parvum selectively up-regulated human beta-defensin-2 in directly infected cells, and inhibition of TLR2 and TLR4 signals or NF-kappaB activation were each associated with a reduction of C. parvum-induced human beta-defensin-2 expression. A significantly higher number of parasites were detected in cells transfected with a MyD88 dominant-negative mutant than in the control cells at 48-96 h after initial exposure to parasites, suggesting MyD88-deficient cells were more susceptible to infection. These findings demonstrate that cholangiocytes express a variety of TLRs, and suggest that TLR2 and TLR4 mediate cholangiocyte defense responses to C. parvum via activation of NF-kappaB. 相似文献
8.
Albart Coster John WM Bastiaansen Mario PL Calus Johan AM van Arendonk Henk Bovenhuis 《遗传、选种与进化》2010,42(1):9
The objective of this simulation study was to compare the effect of the number of QTL and distribution of QTL variance on the accuracy of breeding values estimated with genomewide markers (MEBV). Three distinct methods were used to calculate MEBV: a Bayesian Method (BM), Least Angle Regression (LARS) and Partial Least Square Regression (PLSR). The accuracy of MEBV calculated with BM and LARS decreased when the number of simulated QTL increased. The accuracy decreased more when QTL had different variance values than when all QTL had an equal variance. The accuracy of MEBV calculated with PLSR was affected neither by the number of QTL nor by the distribution of QTL variance. Additional simulations and analyses showed that these conclusions were not affected by the number of individuals in the training population, by the number of markers and by the heritability of the trait. Results of this study show that the effect of the number of QTL and distribution of QTL variance on the accuracy of MEBV depends on the method that is used to calculate MEBV. 相似文献
9.
KR Rupesh PL PremKumar Vasanth V Shiva Kumar Seetharaman S Jayachandran 《BMC microbiology》2002,2(1):5-7
Background
Seeds of the legume plant Lathyrus sativus, which is grown in arid and semi arid tropical regions, contain Diamino Propionic acid (DAP). DAP is a neurotoxin, which, when consumed, causes a disease called Lathyrism. Lathryrism may manifest as Neurolathyrism or Osteolathyrism, in which the nervous system, and bone formation respectively, are affected. DAP ammonia lyase is produced by a few microorganisms such as Salmonella typhi, Salmonella typhimurium and Pseudomonas, and is capable of detoxifying DAP. 相似文献10.