Interferon Regulatory Factor-2 (IRF-2) belongs to IRF family, was identified as a mammalian transcription factor involved in Interferon beta (IFNβ) gene regulation. Besides that IRF-2 is involved in immunomodulation,...Interferon Regulatory Factor-2 (IRF-2) belongs to IRF family, was identified as a mammalian transcription factor involved in Interferon beta (IFNβ) gene regulation. Besides that IRF-2 is involved in immunomodulation, hematopoietic differentiation, cell cycle regulation and oncogenesis. We have done molecular sub-cloning and expression of recombinant murine IRF-2 as GST (Glutathione-S-Transferase)- IRF-2 fusion protein in E. coli/XL-1blue cells. Recombinant IRF-2 with GST moiety at N-terminus expressed as GST-IRF-2 (~66 kd) in E. coli along with different low molecular mass degradation products revealed approximately 30, 42, 60 and 62 kd by SDS-PAGE and Western blot, respectively. We further confirm that degradation takes place at C-terminus of the fusion protein not at N-terminus as anti-GST antibody was detecting all bands in the immunoblot. The recombinant IRF-2 was biologically active along with their degradation products in terms of their DNA binding activity as assessed by Electrophoretically Mobility Shift Assay (EMSA). We observed three different molecular mass DNA/protein complexes (1 - 3) with Virus Response Element (VRE) derived from human Interferon IFNβ gene and five different molecular mass complexes (1 - 5) with IRF-E motif (GAAAGT)4 in EMSA gel. GST only expressed from empty vector did not bind to these DNA elements. To confirm that the binding is specific, all complexes were competed out completely when challenged with 100-X fold molar excess of IRF-E oligo under cold competition. It means degradation products along with full-length protein are able to interact with VREβ as well as IRF-E motif. This means degradation products may regulate the target gene (s) activation/repression via interacting with VRE/IRF-E.展开更多
Objective:To determine how biochanin-A(BCA)affects high-fat diet and streptozotocin-induced pathological changes in lipid metabolism and antioxidant status in diabetic rats.Methods:Diabetic rats were orally administer...Objective:To determine how biochanin-A(BCA)affects high-fat diet and streptozotocin-induced pathological changes in lipid metabolism and antioxidant status in diabetic rats.Methods:Diabetic rats were orally administered BCA(10 mg/kg body weight)for 30 days to investigate its effects on lipid profiles and oxidative stress markers in the liver and kidney.In addition,the mRNA expression of antioxidant and lipid metabolism enzymes in the liver was examined.Results:BCA attenuated hyperlipidemia by regulating mRNA expressions of HMG-CoA reductase,fatty acid synthase,carnitine palmitoyl transferase,and acetyl-CoA carboxylase.Additionally,BCA reduced high-fat diet and streptozotocin-induced oxidative stress by suppressing lipid peroxidation,improving superoxide dismutase,catalase,and glutathione peroxidase levels,and upregulating mRNA expressions of these enzymes.Conclusions:BCA may be a promising nutraceutical for the treatment of dyslipidemia and oxidative stress associated with diabetes.展开更多
Background: The Plain-backed Thrush Zoothera mollissima breeds in the Himalayas and mountains of central China. It was long considered conspecific with the Long-tailed Thrush Zoothera dixoni, until these were shown to...Background: The Plain-backed Thrush Zoothera mollissima breeds in the Himalayas and mountains of central China. It was long considered conspecific with the Long-tailed Thrush Zoothera dixoni, until these were shown to be broadly sympatric.Methods: We revise the Z. mollissima–Z. dixoni complex by integrating morphological, acoustic, genetic(two mitochondrial and two nuclear markers), ecological and distributional datasets.Results: In earlier field observations, we noted two very different song types of "Plain-backed" Thrush segregated by breeding habitat and elevation. Further integrative analyses congruently identify three groups: an alpine breeder in the Himalayas and Sichuan, China("Alpine Thrush"); a forest breeder in the eastern Himalayas and northwest Yunnan(at least), China("Himalayan Forest Thrush"); and a forest breeder in central Sichuan("Sichuan Forest Thrush"). Alpine and Himalayan Forest Thrushes are broadly sympatric, but segregated by habitat and altitude, and the same is probably true also for Alpine and Sichuan Forest Thrushes. These three groups differ markedly in morphology and songs. In addition, DNA sequence data from three non-breeding specimens from Yunnan indicate that yet another lineage exists("Yunnan Thrush"). However, we find no consistent morphological differences from Alpine Thrush, and its breeding range is unknown. Molecular phylogenetic analyses suggest that all four groups diverged at least a few million years ago, and identify Alpine Thrush and the putative "Yunnan Thrush" as sisters, and the two forest taxa as sisters. Cytochrome b divergences among the four Z. mollissima sensu lato(s.l.) clades are similar to those between any of them and Z. dixoni, and exceed that between the two congeneric outgroup species. We lectotypify the name Oreocincla rostrata Hodgson, 1845 with the Z. mollissima sensu stricto(s.s.) specimen long considered its type. No available name unambiguously pertains to the Himalayan Forest Thrush.Conclusions: The Plain-backed Thrush Z. mollissima s.l. comprises at least three species: Alpine Thrush Z. mollissima s.s., with a widespread alpine breeding distribution; Sichuan Forest Thrush Z. griseiceps, breeding in central Sichuan forests; and Himalayan Forest Thrush, breeding in the eastern Himalayas and northwest Yunnan(at least), which is described herein as a new species. "Yunnan Thrush" requires further study.展开更多
The highly speciose gekkonid genus Cnemaspis Strauch,1887 is polyphyletic,with three distantly related and geographically isolated clades from Africa,South Asia(SA),and Southeast Asia.At present,there are 85 known spe...The highly speciose gekkonid genus Cnemaspis Strauch,1887 is polyphyletic,with three distantly related and geographically isolated clades from Africa,South Asia(SA),and Southeast Asia.At present,there are 85 known species within SA Cnemaspis,although the number continues to increase rapidly with focused surveys and rigorous taxonomic work.Recent studies have provided valuable insights into the diversity and evolutionary history of SA Cnemaspis;however,most of these studies lack sufficient sampling in the Western Ghats(WG),where the genus has its greatest diversity.We addressed this research gap by conducting extensive sampling across the WG and re-examining museum specimens,thus providing a systematic account of various extant Cnemaspis species along with their distribution and natural history.We described 12 new species and a southern WG endemic clade of SA Cnemaspis.Ten of the newly described species are endemic to the forests of the southern WG.We also identified 10 well-supported subclades that can be separated across morphological,geographic,and phylogenetic axes.A time-calibrated phylogeny and ancestral area reconstructions confirmed the Paleocene origin of SA Cnemaspis in the WG and provide insights into its evolutionary history and biogeography.The discovery of multiple endemic and deeply divergent lineages further highlights the evolutionary significance of the WG for lizards.展开更多
Asian cultivated rice shows allelic variation in sodium transporter,OsHKT1;5,correlating with shoot sodium exclusion(salinity tolerance).These changes map to intra/extracellularly-oriented loops that occur between fou...Asian cultivated rice shows allelic variation in sodium transporter,OsHKT1;5,correlating with shoot sodium exclusion(salinity tolerance).These changes map to intra/extracellularly-oriented loops that occur between four transmembrane-P loop-transmembrane(MPM)motifs in OsHKT1;5.HKT1;5 sequences from more recently evolved Oryza species(O.sativa/O.officinalis complex species)contain two expansions that involve two intracellularly oriented loops/helical regions between MPM domains,potentially governing transport characteristics,while more ancestral HKT1;5 sequences have shorter intracellular loops.We compared homology models for homoeologous OcHKT 1;5-K and OcHKT1;5-L from halophytic O.coarctata to identify complementary amino acid residues in OcHKT1;5-L that potentially enhance affinity for Na+.Using haplotyping,we showed that Asian cultivated rice accessions only have a fraction of HKT1;5 diversity available in progenitor wild rice species(O.nivara and O.rufipogon).Progenitor HKT1;5 haplotypes can thus be used as novel potential donors for enhancing cultivated rice salinity tolerance.Within Asian rice accessions,10 non-synonymous HKT1;5 haplotypic groups occur.More HKT1;5 haplotypic diversities occur in cultivated indica gene pool compared to japonica.Predominant Haplotypes 2 and 10 occur in mutually exclusive japonica and indica groups,corresponding to haplotypes in O.sativa salt-sensitive and salt-tolerant landraces,respectively.This distinct haplotype partitioning may have originated in separate ancestral gene pools of indica and japonica,or from different haplotypes selected during domestication.Predominance of specific HKT1;5 haplotypes within the 3000 rice dataset may relate to eco-physiological fitness in specific geo-climatic and/or edaphic contexts.展开更多
Watercress(Nasturtium officinale R.Br.)is a nutrient intense,leafy crop that is consumed raw or in soups across the globe,but for which,currently no genomic resources or breeding programme exists.Promising morphologic...Watercress(Nasturtium officinale R.Br.)is a nutrient intense,leafy crop that is consumed raw or in soups across the globe,but for which,currently no genomic resources or breeding programme exists.Promising morphological,biochemical and functional genomic variation was identified for the first time in a newly established watercress germplasm collection,consisting of 48 watercress accessions sourced from contrasting global locations.Stem length,stem diameter and anti-oxidant(AO)potential varied across the accessions.This variation was used to identify three extreme contrasting accessions for further analysis.Variation in global gene expression was investigated using an Affymetrix Arabidopsis ATH1 microarray gene chip,using the commercial control(C),an accession selected for dwarf phenotype with a high AO potential(dwarfAO,called‘Boldrewood’)and one with high AO potential alone.A set of transcripts significantly differentially expressed between these three accessions,were identified,including transcripts involved in the regulation of growth and development and those involved in secondary metabolism.In particular,when differential gene expression was compared between C and dwarfAO,the dwarfAO was characterised by increased expression of genes encoding glucosinolates,which are known precursors of phenethyl isothiocyanate,linked to the anti-carcinogenic effects well-documented in watercress.This study provides the first analysis of natural variation across the watercress genome and has identified important underpinning information for future breeding for enhanced anti-carcinogenic properties and morphology traits in this nutrient-intense crop.展开更多
A diet rich in phytonutrients from fruit and vegetables has been acknowledged to afford protection against a range of human diseases,but many of the most popular vegetables are low in phytonutrients.Wild relatives of ...A diet rich in phytonutrients from fruit and vegetables has been acknowledged to afford protection against a range of human diseases,but many of the most popular vegetables are low in phytonutrients.Wild relatives of crops may contain allelic variation for genes determining the concentrations of these beneficial phytonutrients,and therefore understanding the genetic basis of this variation is important for breeding efforts to enhance nutritional quality.In this study,lettuce recombinant inbred lines,generated from a cross between wild and cultivated lettuce(Lactuca serriola and Lactuca sativa,respectively),were analysed for antioxidant(AO)potential and important phytonutrients including carotenoids,chlorophyll and phenolic compounds.When grown in two environments,96 quantitative trait loci(QTL)were identified for these nutritional traits:4 for AO potential,2 for carotenoid content,3 for total chlorophyll content and 87 for individual phenolic compounds(two per compound on average).Most often,the L.serriola alleles conferred an increase in total AOs and metabolites.Candidate genes underlying these QTL were identified by BLASTn searches;in several cases,these had functions suggesting involvement in phytonutrient biosynthetic pathways.Analysis of a QTL on linkage group 3,which accounted for>30%of the variation in AO potential,revealed several candidate genes encoding multiple MYB transcription factors which regulate flavonoid biosynthesis and flavanone 3-hydroxylase,an enzyme involved in the biosynthesis of the flavonoids quercetin and kaempferol,which are known to have powerful AO activity.Follow-up quantitative RT-PCR of these candidates revealed that 5 out of 10 genes investigated were significantly differentially expressed between the wild and cultivated parents,providing further evidence of their potential involvement in determining the contrasting phenotypes.These results offer exciting opportunities to improve the nutritional content and health benefits of lettuce through marker-assisted breeding.展开更多
Dear Editor, Gram-negative bacteria utilize the acid sugar 2-keto-3-deoxymanno-octulosonic acid (Kdo) as an essential component of the lipopolysaccharide (LPS). The enzyme CMP-Kdo synthetase (KdsB) is required ...Dear Editor, Gram-negative bacteria utilize the acid sugar 2-keto-3-deoxymanno-octulosonic acid (Kdo) as an essential component of the lipopolysaccharide (LPS). The enzyme CMP-Kdo synthetase (KdsB) is required to activate Kdo prior to incorporation into the LPS, utilizing Kdo and CTP to form CMP-Kdo and pyrophosphate.展开更多
Preventive medicine and food industry have shown an increased interest in the development of natural antioxidants,since those most commonly used synthetic antioxidants may have restricted use in food.This could explai...Preventive medicine and food industry have shown an increased interest in the development of natural antioxidants,since those most commonly used synthetic antioxidants may have restricted use in food.This could explain why there is currently much research on the antioxidant properties from natural products such as mushrooms.Many mushrooms have been reported to possess antioxidant properties,which enable them to neutralize free radicals.The oxygen molecule is a free radical,which lead to the generation of the reactive oxygen species and can damage the cells.Cell damage caused by free radicals appears to be a major contributor to aging and degenerative diseases.Mushrooms antioxidant components are found in fruit bodies,mycelium and culture both,which include polysaccharides,tocopherols,phenolics,carotenoids,ergosterol and ascorbic acid among others.Fruit bodies or mycelium can be manipulated to produce active compounds in a relatively short period of time,which represent a significant advantage in antioxidant compounds extraction from mushrooms.Antioxidant compounds may be extracted to be used as functional additives or mushrooms can be incorporated into our food regime,representing an alternative source of food to prevent damage caused by oxidation in the human body.展开更多
Unlike birds, insects lack control surfaces at the tail and hence most insects modify their wing kinematics to produce control forces or moments while flapping their wings. Change of the flapping angle range is one of...Unlike birds, insects lack control surfaces at the tail and hence most insects modify their wing kinematics to produce control forces or moments while flapping their wings. Change of the flapping angle range is one of the ways to modify wing kinematics, resulting in relocation of the mean Aerodynamic force Center (mean AC) and finally creating control moments. In an attempt to mimic this feature, we developed a flapping-wing system that generates a desired pitching moment during flap- ping-wing motion. The system comprises a flapping mechanism that creates a large and symmetric flapping motion in a pair of wings, a flapping angle change mechanism that modifies the flapping angle range, artificial wings, and a power source. From the measured wing kinematics, we have found that the flapping-wing system can properly modify the flapping angle ranges. The measured pitching moments show that the flapping-wing system generates a pitching moment in a desired direction by shifting the flapping angle range. We also demonstrated that the system can in practice change the longitudinal attitude by generating a nonzero pitching moment.展开更多
The discovery of microRNAs (miRNAs) is one of tbe most significant breakthroughs in recent decades, miRNAs are a class of small, endogenous, non-coding RNAs (19-24 nt) that negatively regulate the expression of ta...The discovery of microRNAs (miRNAs) is one of tbe most significant breakthroughs in recent decades, miRNAs are a class of small, endogenous, non-coding RNAs (19-24 nt) that negatively regulate the expression of target genes by binding to their 3' untranslated region and are involved in various biological processes. Three main approaches that are globally used for the detection of miRNA include direct cloning, forward genetics and computational approaches using bioinformatics.展开更多
Humankind draws important benefits from large-scale ecological processes termed ecosystem services, yet the status of several of them is declining. Reliable monitoring methods are essential for tracking the status of ...Humankind draws important benefits from large-scale ecological processes termed ecosystem services, yet the status of several of them is declining. Reliable monitoring methods are essential for tracking the status of ecosystem services. Predation is the mainstay of natural pest control, a key ecosystem service. We used green plasticine caterpillars to monitor predation pressure, and to obtain baseline data on predator activity in transgenic Bt versus non-Bt maize fields in Old and New World countries. Predation pressure was measured at ground and canopy levels using an identical, small-plot experimental design in four European countries (Denmark, Slovakia, Romania and Italy) and Argentina. Total predation rate in maize was l l.7%d^-1 (min. 7.2%d^-1 in Argentina, max. 29.0%d^-1 in Romania). Artificial caterpillars were attacked both by invertebrates (mostly chewing insects with 42.0% of the attack marks, and ants with 7.1%, but also predatory and parasitoid wasps, spiders and slugs), and vertebrates (small mammals 25.5%, and birds 20.2%). Total predation at ground level (15.7%d^-1) was significantly higher than in maize canopies (6.0%d^-1) in all countries, except Argentina. We found no significant differences between predator pressure in Bt versus non-Bt maize plots. The artificial caterpillar method provided comparable, quantitative data on predation intensity, and proved to be suitable for monitoring natural pest control. This method usefully expands the existing toolkit by directly measuring ecological function rather than structure.展开更多
Aims Annually variable but synchronous production of large seed crops(‘masting’)is a widespread phenomenon in temperate trees.Mounting concerns about the impacts of anthropogenic climate change(ACC)on plant reproduc...Aims Annually variable but synchronous production of large seed crops(‘masting’)is a widespread phenomenon in temperate trees.Mounting concerns about the impacts of anthropogenic climate change(ACC)on plant reproduction gives urgency to our need to understand better the role of climate on tree reproduction,and in particular,mast events.Unlike our understanding of reproductive phenology however,there is little consensus regarding how climate affects plant reproductive effort or indeed the actual environmental triggers that underpin masting behaviour.Methods We used a 27-year record of acorn yield from a population of 12 Quercus robur trees located in southern England to compare mast-ing frequency and post-dispersal acorn yield each year for each tree,with long-term weather data over the same period.We focussed on discrete or sequential climate cues(temperature,precipitation and frost days)as likely predictors of oak reproduction.Important Findings Annual post-dispersal acorn crop varied greatly;i.e.no acorns in 14 of the 27 years,but there was no sequential pattern of crop ver-sus non-crop years indicating that weather,rather than resource limitation alone,dictated the timing of reproduction.Crop years were instead most closely associated with relatively cool late sum-mer conditions in the preceding year,followed by anomalous sum-mer warmth within crop year.Acorn yield increased following dry April and above-average May and June temperatures within crop year.Although our results support a general association between warm late spring and summer conditions,and crop frequency and yield,respectively,the influence of cooler later summer conditions in the year prior to masting highlights how a combination of weather cues may dictate the occurrence of mast years.Consequently,our results corroborate not only the hypothesis that temperature differ-entials between consecutive years,not absolute temperatures,may be the better predictor of mast seeding events but lend support also to the suggestion that reproductive failure and resource accumu-lation resulting from a climate-linked environmental veto,drives future reproductive synchronization in temperate tree species.展开更多
文摘Interferon Regulatory Factor-2 (IRF-2) belongs to IRF family, was identified as a mammalian transcription factor involved in Interferon beta (IFNβ) gene regulation. Besides that IRF-2 is involved in immunomodulation, hematopoietic differentiation, cell cycle regulation and oncogenesis. We have done molecular sub-cloning and expression of recombinant murine IRF-2 as GST (Glutathione-S-Transferase)- IRF-2 fusion protein in E. coli/XL-1blue cells. Recombinant IRF-2 with GST moiety at N-terminus expressed as GST-IRF-2 (~66 kd) in E. coli along with different low molecular mass degradation products revealed approximately 30, 42, 60 and 62 kd by SDS-PAGE and Western blot, respectively. We further confirm that degradation takes place at C-terminus of the fusion protein not at N-terminus as anti-GST antibody was detecting all bands in the immunoblot. The recombinant IRF-2 was biologically active along with their degradation products in terms of their DNA binding activity as assessed by Electrophoretically Mobility Shift Assay (EMSA). We observed three different molecular mass DNA/protein complexes (1 - 3) with Virus Response Element (VRE) derived from human Interferon IFNβ gene and five different molecular mass complexes (1 - 5) with IRF-E motif (GAAAGT)4 in EMSA gel. GST only expressed from empty vector did not bind to these DNA elements. To confirm that the binding is specific, all complexes were competed out completely when challenged with 100-X fold molar excess of IRF-E oligo under cold competition. It means degradation products along with full-length protein are able to interact with VREβ as well as IRF-E motif. This means degradation products may regulate the target gene (s) activation/repression via interacting with VRE/IRF-E.
文摘Objective:To determine how biochanin-A(BCA)affects high-fat diet and streptozotocin-induced pathological changes in lipid metabolism and antioxidant status in diabetic rats.Methods:Diabetic rats were orally administered BCA(10 mg/kg body weight)for 30 days to investigate its effects on lipid profiles and oxidative stress markers in the liver and kidney.In addition,the mRNA expression of antioxidant and lipid metabolism enzymes in the liver was examined.Results:BCA attenuated hyperlipidemia by regulating mRNA expressions of HMG-CoA reductase,fatty acid synthase,carnitine palmitoyl transferase,and acetyl-CoA carboxylase.Additionally,BCA reduced high-fat diet and streptozotocin-induced oxidative stress by suppressing lipid peroxidation,improving superoxide dismutase,catalase,and glutathione peroxidase levels,and upregulating mRNA expressions of these enzymes.Conclusions:BCA may be a promising nutraceutical for the treatment of dyslipidemia and oxidative stress associated with diabetes.
基金financial support from the Ministry of Science and Technology of China(Grant No.2014FY210200,to.T.C.and Y.G.)the Russian Science Foundation(Project No.14-50-00029,to M.K.)+3 种基金the Delia Koo Global Faculty Endowment of the Asian Studies Center,Michigan State University(to P.C.R.)The Sound Approach and Jornvall Foundation(both to P.A.and U.O.)the Chinese Academy of Sciences Visiting Professorship for Senior International Scientists(No.2011T2S04,to P.A.)Swarovski Optik Greater China(to P.A.)
文摘Background: The Plain-backed Thrush Zoothera mollissima breeds in the Himalayas and mountains of central China. It was long considered conspecific with the Long-tailed Thrush Zoothera dixoni, until these were shown to be broadly sympatric.Methods: We revise the Z. mollissima–Z. dixoni complex by integrating morphological, acoustic, genetic(two mitochondrial and two nuclear markers), ecological and distributional datasets.Results: In earlier field observations, we noted two very different song types of "Plain-backed" Thrush segregated by breeding habitat and elevation. Further integrative analyses congruently identify three groups: an alpine breeder in the Himalayas and Sichuan, China("Alpine Thrush"); a forest breeder in the eastern Himalayas and northwest Yunnan(at least), China("Himalayan Forest Thrush"); and a forest breeder in central Sichuan("Sichuan Forest Thrush"). Alpine and Himalayan Forest Thrushes are broadly sympatric, but segregated by habitat and altitude, and the same is probably true also for Alpine and Sichuan Forest Thrushes. These three groups differ markedly in morphology and songs. In addition, DNA sequence data from three non-breeding specimens from Yunnan indicate that yet another lineage exists("Yunnan Thrush"). However, we find no consistent morphological differences from Alpine Thrush, and its breeding range is unknown. Molecular phylogenetic analyses suggest that all four groups diverged at least a few million years ago, and identify Alpine Thrush and the putative "Yunnan Thrush" as sisters, and the two forest taxa as sisters. Cytochrome b divergences among the four Z. mollissima sensu lato(s.l.) clades are similar to those between any of them and Z. dixoni, and exceed that between the two congeneric outgroup species. We lectotypify the name Oreocincla rostrata Hodgson, 1845 with the Z. mollissima sensu stricto(s.s.) specimen long considered its type. No available name unambiguously pertains to the Himalayan Forest Thrush.Conclusions: The Plain-backed Thrush Z. mollissima s.l. comprises at least three species: Alpine Thrush Z. mollissima s.s., with a widespread alpine breeding distribution; Sichuan Forest Thrush Z. griseiceps, breeding in central Sichuan forests; and Himalayan Forest Thrush, breeding in the eastern Himalayas and northwest Yunnan(at least), which is described herein as a new species. "Yunnan Thrush" requires further study.
基金This study was supported by the Critical Ecosystem Partnership Fund(Western Ghats)DBT-IISc Partnership Programme and Ministry of Environment,Forests,and Climate Change(MoEFCC)Singinawa Conservation Foundation,and Rufford Small Grant。
文摘The highly speciose gekkonid genus Cnemaspis Strauch,1887 is polyphyletic,with three distantly related and geographically isolated clades from Africa,South Asia(SA),and Southeast Asia.At present,there are 85 known species within SA Cnemaspis,although the number continues to increase rapidly with focused surveys and rigorous taxonomic work.Recent studies have provided valuable insights into the diversity and evolutionary history of SA Cnemaspis;however,most of these studies lack sufficient sampling in the Western Ghats(WG),where the genus has its greatest diversity.We addressed this research gap by conducting extensive sampling across the WG and re-examining museum specimens,thus providing a systematic account of various extant Cnemaspis species along with their distribution and natural history.We described 12 new species and a southern WG endemic clade of SA Cnemaspis.Ten of the newly described species are endemic to the forests of the southern WG.We also identified 10 well-supported subclades that can be separated across morphological,geographic,and phylogenetic axes.A time-calibrated phylogeny and ancestral area reconstructions confirmed the Paleocene origin of SA Cnemaspis in the WG and provide insights into its evolutionary history and biogeography.The discovery of multiple endemic and deeply divergent lineages further highlights the evolutionary significance of the WG for lizards.
基金supported by the Department of Biotechnology,Government of India(Grant No.BT/PR11396/NDB/52/118/2008)and Council for Scientific and Industrial Research,India for Senior Research Fellowship(Grant No.09/656(0018)/2016-EMR-1)to Shalini PULIPATIfunding and support provided by JC Bose Fellowship(Grant No.SB/S2/JC-071/2015)from Science and Engineering Research Board,India and Bioinformatics Centre Grant funded by Department of Biotechnology,India(Grant No.BT/PR40187/BTIS/137/9/2021)。
文摘Asian cultivated rice shows allelic variation in sodium transporter,OsHKT1;5,correlating with shoot sodium exclusion(salinity tolerance).These changes map to intra/extracellularly-oriented loops that occur between four transmembrane-P loop-transmembrane(MPM)motifs in OsHKT1;5.HKT1;5 sequences from more recently evolved Oryza species(O.sativa/O.officinalis complex species)contain two expansions that involve two intracellularly oriented loops/helical regions between MPM domains,potentially governing transport characteristics,while more ancestral HKT1;5 sequences have shorter intracellular loops.We compared homology models for homoeologous OcHKT 1;5-K and OcHKT1;5-L from halophytic O.coarctata to identify complementary amino acid residues in OcHKT1;5-L that potentially enhance affinity for Na+.Using haplotyping,we showed that Asian cultivated rice accessions only have a fraction of HKT1;5 diversity available in progenitor wild rice species(O.nivara and O.rufipogon).Progenitor HKT1;5 haplotypes can thus be used as novel potential donors for enhancing cultivated rice salinity tolerance.Within Asian rice accessions,10 non-synonymous HKT1;5 haplotypic groups occur.More HKT1;5 haplotypic diversities occur in cultivated indica gene pool compared to japonica.Predominant Haplotypes 2 and 10 occur in mutually exclusive japonica and indica groups,corresponding to haplotypes in O.sativa salt-sensitive and salt-tolerant landraces,respectively.This distinct haplotype partitioning may have originated in separate ancestral gene pools of indica and japonica,or from different haplotypes selected during domestication.Predominance of specific HKT1;5 haplotypes within the 3000 rice dataset may relate to eco-physiological fitness in specific geo-climatic and/or edaphic contexts.
基金Research on watercress in the laboratory of GT is supported by The University of Southampton and Vitacress Salads Ltd.
文摘Watercress(Nasturtium officinale R.Br.)is a nutrient intense,leafy crop that is consumed raw or in soups across the globe,but for which,currently no genomic resources or breeding programme exists.Promising morphological,biochemical and functional genomic variation was identified for the first time in a newly established watercress germplasm collection,consisting of 48 watercress accessions sourced from contrasting global locations.Stem length,stem diameter and anti-oxidant(AO)potential varied across the accessions.This variation was used to identify three extreme contrasting accessions for further analysis.Variation in global gene expression was investigated using an Affymetrix Arabidopsis ATH1 microarray gene chip,using the commercial control(C),an accession selected for dwarf phenotype with a high AO potential(dwarfAO,called‘Boldrewood’)and one with high AO potential alone.A set of transcripts significantly differentially expressed between these three accessions,were identified,including transcripts involved in the regulation of growth and development and those involved in secondary metabolism.In particular,when differential gene expression was compared between C and dwarfAO,the dwarfAO was characterised by increased expression of genes encoding glucosinolates,which are known precursors of phenethyl isothiocyanate,linked to the anti-carcinogenic effects well-documented in watercress.This study provides the first analysis of natural variation across the watercress genome and has identified important underpinning information for future breeding for enhanced anti-carcinogenic properties and morphology traits in this nutrient-intense crop.
基金Research was funded by a BBSRC studentship to GFB and funding from Vitacress LtdSainsbury’s Supermarkets Ltd and Shamrock Seeds Ltd in the laboratory of Gail TaylorThe contributions of MJT and RWM were supported by a grant from USDA NIFA SCRI No.2010-51181-21631 as well as funding from the California Leafy Greens Research Board.
文摘A diet rich in phytonutrients from fruit and vegetables has been acknowledged to afford protection against a range of human diseases,but many of the most popular vegetables are low in phytonutrients.Wild relatives of crops may contain allelic variation for genes determining the concentrations of these beneficial phytonutrients,and therefore understanding the genetic basis of this variation is important for breeding efforts to enhance nutritional quality.In this study,lettuce recombinant inbred lines,generated from a cross between wild and cultivated lettuce(Lactuca serriola and Lactuca sativa,respectively),were analysed for antioxidant(AO)potential and important phytonutrients including carotenoids,chlorophyll and phenolic compounds.When grown in two environments,96 quantitative trait loci(QTL)were identified for these nutritional traits:4 for AO potential,2 for carotenoid content,3 for total chlorophyll content and 87 for individual phenolic compounds(two per compound on average).Most often,the L.serriola alleles conferred an increase in total AOs and metabolites.Candidate genes underlying these QTL were identified by BLASTn searches;in several cases,these had functions suggesting involvement in phytonutrient biosynthetic pathways.Analysis of a QTL on linkage group 3,which accounted for>30%of the variation in AO potential,revealed several candidate genes encoding multiple MYB transcription factors which regulate flavonoid biosynthesis and flavanone 3-hydroxylase,an enzyme involved in the biosynthesis of the flavonoids quercetin and kaempferol,which are known to have powerful AO activity.Follow-up quantitative RT-PCR of these candidates revealed that 5 out of 10 genes investigated were significantly differentially expressed between the wild and cultivated parents,providing further evidence of their potential involvement in determining the contrasting phenotypes.These results offer exciting opportunities to improve the nutritional content and health benefits of lettuce through marker-assisted breeding.
文摘Dear Editor, Gram-negative bacteria utilize the acid sugar 2-keto-3-deoxymanno-octulosonic acid (Kdo) as an essential component of the lipopolysaccharide (LPS). The enzyme CMP-Kdo synthetase (KdsB) is required to activate Kdo prior to incorporation into the LPS, utilizing Kdo and CTP to form CMP-Kdo and pyrophosphate.
文摘Preventive medicine and food industry have shown an increased interest in the development of natural antioxidants,since those most commonly used synthetic antioxidants may have restricted use in food.This could explain why there is currently much research on the antioxidant properties from natural products such as mushrooms.Many mushrooms have been reported to possess antioxidant properties,which enable them to neutralize free radicals.The oxygen molecule is a free radical,which lead to the generation of the reactive oxygen species and can damage the cells.Cell damage caused by free radicals appears to be a major contributor to aging and degenerative diseases.Mushrooms antioxidant components are found in fruit bodies,mycelium and culture both,which include polysaccharides,tocopherols,phenolics,carotenoids,ergosterol and ascorbic acid among others.Fruit bodies or mycelium can be manipulated to produce active compounds in a relatively short period of time,which represent a significant advantage in antioxidant compounds extraction from mushrooms.Antioxidant compounds may be extracted to be used as functional additives or mushrooms can be incorporated into our food regime,representing an alternative source of food to prevent damage caused by oxidation in the human body.
文摘Unlike birds, insects lack control surfaces at the tail and hence most insects modify their wing kinematics to produce control forces or moments while flapping their wings. Change of the flapping angle range is one of the ways to modify wing kinematics, resulting in relocation of the mean Aerodynamic force Center (mean AC) and finally creating control moments. In an attempt to mimic this feature, we developed a flapping-wing system that generates a desired pitching moment during flap- ping-wing motion. The system comprises a flapping mechanism that creates a large and symmetric flapping motion in a pair of wings, a flapping angle change mechanism that modifies the flapping angle range, artificial wings, and a power source. From the measured wing kinematics, we have found that the flapping-wing system can properly modify the flapping angle ranges. The measured pitching moments show that the flapping-wing system generates a pitching moment in a desired direction by shifting the flapping angle range. We also demonstrated that the system can in practice change the longitudinal attitude by generating a nonzero pitching moment.
文摘The discovery of microRNAs (miRNAs) is one of tbe most significant breakthroughs in recent decades, miRNAs are a class of small, endogenous, non-coding RNAs (19-24 nt) that negatively regulate the expression of target genes by binding to their 3' untranslated region and are involved in various biological processes. Three main approaches that are globally used for the detection of miRNA include direct cloning, forward genetics and computational approaches using bioinformatics.
文摘Humankind draws important benefits from large-scale ecological processes termed ecosystem services, yet the status of several of them is declining. Reliable monitoring methods are essential for tracking the status of ecosystem services. Predation is the mainstay of natural pest control, a key ecosystem service. We used green plasticine caterpillars to monitor predation pressure, and to obtain baseline data on predator activity in transgenic Bt versus non-Bt maize fields in Old and New World countries. Predation pressure was measured at ground and canopy levels using an identical, small-plot experimental design in four European countries (Denmark, Slovakia, Romania and Italy) and Argentina. Total predation rate in maize was l l.7%d^-1 (min. 7.2%d^-1 in Argentina, max. 29.0%d^-1 in Romania). Artificial caterpillars were attacked both by invertebrates (mostly chewing insects with 42.0% of the attack marks, and ants with 7.1%, but also predatory and parasitoid wasps, spiders and slugs), and vertebrates (small mammals 25.5%, and birds 20.2%). Total predation at ground level (15.7%d^-1) was significantly higher than in maize canopies (6.0%d^-1) in all countries, except Argentina. We found no significant differences between predator pressure in Bt versus non-Bt maize plots. The artificial caterpillar method provided comparable, quantitative data on predation intensity, and proved to be suitable for monitoring natural pest control. This method usefully expands the existing toolkit by directly measuring ecological function rather than structure.
文摘Aims Annually variable but synchronous production of large seed crops(‘masting’)is a widespread phenomenon in temperate trees.Mounting concerns about the impacts of anthropogenic climate change(ACC)on plant reproduction gives urgency to our need to understand better the role of climate on tree reproduction,and in particular,mast events.Unlike our understanding of reproductive phenology however,there is little consensus regarding how climate affects plant reproductive effort or indeed the actual environmental triggers that underpin masting behaviour.Methods We used a 27-year record of acorn yield from a population of 12 Quercus robur trees located in southern England to compare mast-ing frequency and post-dispersal acorn yield each year for each tree,with long-term weather data over the same period.We focussed on discrete or sequential climate cues(temperature,precipitation and frost days)as likely predictors of oak reproduction.Important Findings Annual post-dispersal acorn crop varied greatly;i.e.no acorns in 14 of the 27 years,but there was no sequential pattern of crop ver-sus non-crop years indicating that weather,rather than resource limitation alone,dictated the timing of reproduction.Crop years were instead most closely associated with relatively cool late sum-mer conditions in the preceding year,followed by anomalous sum-mer warmth within crop year.Acorn yield increased following dry April and above-average May and June temperatures within crop year.Although our results support a general association between warm late spring and summer conditions,and crop frequency and yield,respectively,the influence of cooler later summer conditions in the year prior to masting highlights how a combination of weather cues may dictate the occurrence of mast years.Consequently,our results corroborate not only the hypothesis that temperature differ-entials between consecutive years,not absolute temperatures,may be the better predictor of mast seeding events but lend support also to the suggestion that reproductive failure and resource accumu-lation resulting from a climate-linked environmental veto,drives future reproductive synchronization in temperate tree species.