Tissue homeostasis, accomplished through the self-renewai and differentiation of resident stem cells, is critical for the maintenance of adult tissues throughout an animal＇s lifetime, Adult Drosophila Malpighian tubu...Tissue homeostasis, accomplished through the self-renewai and differentiation of resident stem cells, is critical for the maintenance of adult tissues throughout an animal＇s lifetime, Adult Drosophila Malpighian tubules （MTs or fly kidney） are maintained by renal and nephric stem cells （RNSCs） via self-renewing divisions, however, it is unclear how RNSC proliferation and differentiation are regulated. Here we show that EGFR/MAPK signaling is dispensable for RNSC maintenance, but required for RNSC proliferation in vivo. Inacti- vation of the EGFR/MAPK pathway blocks or greatly retards RNSC cell cycle progression; conversely, over-activation of EGFR/MAPK signaling results in RNSC over-proliferation and disrupts the normal differentiation of renablasts （RBs）, the immediate daughters of RNSC divisions. Our data further suggest that EGFR/MAPK signaling functions independently of JAK/STAT signaling and that dMyc and CycE partially mediate EGFR/MAPK signaling in MTs. Together, our data suggest a principal role of EGFR/MAPK signaling in regulating RNSC proliferation, which may provide important clues for understanding mammalian kidney repair and regeneration following injury.展开更多
Laboratory studies were conducted to evaluate the risk of Phytophthora capsici developing resistance to two morphlines, dimethomorph and flumorph. Metalaxyl, the well-known high risk of resistance fungicides, was used...Laboratory studies were conducted to evaluate the risk of Phytophthora capsici developing resistance to two morphlines, dimethomorph and flumorph. Metalaxyl, the well-known high risk of resistance fungicides, was used as reference fungicide. Resistant mutants for the three fungicides were isolated by treating mycelium with ultraviolet radiation. Metalaxyl-resistant mutants were obtained with high frequency and exhibited high level of resistance with factors more than 100 folds, while mutation frequency for dimethomorph-resistance was relatively low and the resistance factors ranged from 3.0 to 13.9 folds. Most dimethomorph-resistant mutants decreased in hyphal growth rate and the spoulation ability, which have a large impact upon the epidemic development of dimethomorph-resistant populations. These results suggested that the risk of resistant pathogen population was much lower for dimethomorph than for metalaxyl. Both the frequency of developing resistance and level of resistance （resistance factors = 1.8-14.6） to dimethomorph were similar to those of its structure analogue flumorh. Moreover, the cross-resistance were found between them, which suggested the risks of developing resistance to dimethomorph and flumorph in the pathogen were very closely related. As P. capsici can potentially develop resistance to dimethomorph and flumorph, and oomycetes usually have the high risk to develop resistance to fungicides, appropriate management against resistance development should be taken.展开更多
Apolipoprotein E has diverse functions in neurons:Apolipoprotein E(ApoE)is a glycoprotein that primarily regulates lipid metabolism and transport in the central nervous system.There are three predominant human ApoE pr...Apolipoprotein E has diverse functions in neurons:Apolipoprotein E(ApoE)is a glycoprotein that primarily regulates lipid metabolism and transport in the central nervous system.There are three predominant human ApoE protein isoforms with cysteine and arginine substitutions at amino acid positions 112 and 158 that impact their lipidation and related functions(Flowers and Rebeck,2020).ApoE2 is characterized by Cys112 and Cys158,ApoE3 by Cys112 and Arg158,whereas ApoE4 contains Arg112 and Arg158.展开更多
Asian seabass(Lates calcarifer)is becoming an important species for aquaculture.However,the Asian seabass aquaculture industry faces a significant challenge of disease outbreaks that can jeopardize fish health and pro...Asian seabass(Lates calcarifer)is becoming an important species for aquaculture.However,the Asian seabass aquaculture industry faces a significant challenge of disease outbreaks that can jeopardize fish health and production.This review delves into the major diseases affecting Asian seabass aquaculture and explores their causes,symptoms,and management approaches.We focused on the key pathogens responsible for these outbreaks,the environmental factors contributing to disease susceptibility,and the latest advancements in disease prevention and management.By addressing these critical aspects,this review addresses the needs of aquaculturists,researchers,and policymakers with the knowledge required to promote resilient and sustainable Asian seabass farming.We aim to shed light on the challenges posed by disease while highlighting innovative strategies that offer promise for the future of this thriving industry.This comprehensive examination serves as a valuable resource for those invested in ensuring the health and vitality of Asian seabass,securing a consistent supply to meet the demands of global seafood markets.展开更多
On top of genetic information,organisms have evolved complex and sophisticated epigenetic regulation to adjust gene expression in response to developmental and environmental signals.Key epigenetic mechanisms include D...On top of genetic information,organisms have evolved complex and sophisticated epigenetic regulation to adjust gene expression in response to developmental and environmental signals.Key epigenetic mechanisms include DNA methylation,histone modifications and variants,chromatin remodeling,and chemical modifications of RNAs.Epigenetic control of environmental responses is particularly important for plants,which are sessile and unable to move away from adverse environments.Besides enabling plants to rapidly respond to environmental stresses,some stress-induced epigenetic changes can be maintained,providing plants with a pre-adapted state to recurring stresses.Understanding these epigenetic mechanisms offers valuable insights for developing crop varieties with enhanced stress tolerance.Here,we focus on abiotic stresses and summarize recent progress in characterizing stress-induced epigenetic changes and their regulatory mechanisms and roles in plant abiotic stress resistance.展开更多
Influenza A viruses are important human pathogens causing periodic pandemic threats. Nonstructural protein 1 （NS1） protein of influenza A virus （NS1A） shields the virus against host defense. Here, we report the cr...Influenza A viruses are important human pathogens causing periodic pandemic threats. Nonstructural protein 1 （NS1） protein of influenza A virus （NS1A） shields the virus against host defense. Here, we report the crystal structure of NS1A RNA-binding domain （RBD） bound to a double-stranded RNA （dsRNA） at 1.7A. NS1A RBD forms a homodimer to recognize the major groove of A-form dsRNA in a length-independent mode by its conserved concave surface formed by dimeric anti-parallel a-helices, dsRNA is anchored by a pair of invariable arginines （Arg38） from both monomers by extensive hydrogen bonds. In accordance with the structural observation, isothermal titration calorimetry assay shows that the unique Arg38-Arg38 pair and two Arg35-Arg46 pairs are crucial for dsRNA binding, and that Ser42 and Thr49 are also important for dsRNA binding. Agrobacterium co-infiltration assay further supports that the unique Arg38 pair plays important roles in dsRNA binding in vivo.展开更多
Microbial oxidation and reduction of iron and sulfur are important parts of biogeochemical cycles in acidic environments such as geothermal solfataric regions. Species of Acidithiobacillus and Leptospirillum are the c...Microbial oxidation and reduction of iron and sulfur are important parts of biogeochemical cycles in acidic environments such as geothermal solfataric regions. Species of Acidithiobacillus and Leptospirillum are the common ferrous-iron and sulfur oxidizers from such environments. This study focused on the Tengchong sofataric region, located in Yunnan Province, Southwest China. Based on cultivation, 9 strains that grow on ferrous-iron and sulfuric compounds were obtained. Analysis of 16S rRNA genes of the 9 strains indicated that they were affiliated to AcidithiobaciUus, Alicyclobacillus, Sulfobacillus, Leptospirillum and Acidiphilium. Physiological and phylogenetic studies indicated that two strains （TC-34 and TC-71） might represent two novel members of Alicyclobacillus. Strain TC-34 and TC-71 showed 94.8%-97.1% 16S rRNA gene identities to other species of Alicyclobacillus. Different from the previously described Alicyclobacillus species, strains TC-34 and TC-71 were mesophilic and their cellular fatty acids do not contain w-cyclic fatty acids. Strain TC-71 was obligately dependent on ferrous-iron for growth. It was concluded that the ferrous-iron oxidizers were diversified and Alicyclobacillus species were proposed to take part in biochemical geocycling of iron in the Tengchong solfataric region.展开更多
Adrenomedullin,a peptide with multiple physiological functions in nervous system injury and disease,has aroused the interest of researchers.This review summarizes the role of adrenomedullin in neuropathological disord...Adrenomedullin,a peptide with multiple physiological functions in nervous system injury and disease,has aroused the interest of researchers.This review summarizes the role of adrenomedullin in neuropathological disorders,including pathological pain,brain injury and nerve regeneration,and their treatment.As a newly characterized pronociceptive mediator,adrenomedullin has been shown to act as an upstream factor in the transmission of noxious information for various types of pathological pain including acute and chronic inflammatory pain,cancer pain,neuropathic pain induced by spinal nerve injury and diabetic neuropathy.Initiation of glia-neuron signaling networks in the peripheral and central nervous system by adrenomedullin is involved in the formation and maintenance of morphine tolerance.Adrenomedullin has been shown to exert a facilitated or neuroprotective effect against brain injury including hemorrhagic or ischemic stroke and traumatic brain injury.Additionally,adrenomedullin can serve as a regulator to promote nerve regeneration in pathological conditions.Therefore,adrenomedullin is an important participant in nervous system diseases.展开更多
Microsatellites have been widely used in studies on population genetics, ecology and evolutionary biology. However, microsatellites are not always available for the species to be studied and their isolation could be t...Microsatellites have been widely used in studies on population genetics, ecology and evolutionary biology. However, microsatellites are not always available for the species to be studied and their isolation could be time-consuming. In order to save time and effort researchers often rely on cross-species amplification. We revealed a new problem of microsatellite cross-species amplification in addition to size homoplasy by analyzing the sequences of electromorphs from seven catfish species belonging to three different families （Clariidae, Heteropneustidae and Pimelodidae）. A total of 50 different electromorphs were amplified from the seven catfish species by using primers for 4 microsatellite loci isolated from the species Clarias batrachus. Two hundred and forty PCR-products representing all 50 electromorphs were sequenced and analyzed. Primers for two loci amplified specific products from orthologous loci in all species tested, whereas primers for the other two loci produced specific and polymorphic bands from some non-orthologous loci, even in closely related non-source species. Size homoplasy within the source species was not obvious, whereas extensive size homoplasy across species were detected at three loci, but not at the fourth one. These data suggest that amplification of products from non-orthologous loci and appearance of size homoplasy by cross-amplification are locus dependent, and do not reflect phylogenetic relationship. Amplification of non-orthologous loci and appearance of size homoplasy will lead to obvious complications in phylogenetie interference, population genetic and evolutionary studies. Therefore, we propose that sequence analysis of cross-amplification products should be conducted prior to application of cross-species amplification of microsatellites.展开更多
Understanding the genetic basis of phenotypes is of importance in evolutionary biology and for genetic improvement of economically valuable animals.The giant phenotype of the fighting fish,Betta splendens,provides a u...Understanding the genetic basis of phenotypes is of importance in evolutionary biology and for genetic improvement of economically valuable animals.The giant phenotype of the fighting fish,Betta splendens,provides a unique opportunity to explore the genetic architecture of overgrowth in body size.As such,we re-sequenced and analyzed the genomes of 54 fighting fish.Genome-wide FST and selective sweep analyses using 3582429 DNA variants revealed three genomic regions at chr1,chr9,and chr11 that were associated with the giant phenotype.With a total length of~3.5 Mb,these regions showed high divergence between the giant and non-giant bettas.In contrast,no signature of selection was detected in the wild-type fish.Transcriptome analysis of brain and muscle samples from giant and normal bettas identified 14 candidate genes that were likely responsible for the giant phenotype.Overall,our data provide novel insights into the genetic basis of body size variation.The genome sequences,transcriptome sequences,DNA sequence variants,and candidate genes for body size provide valuable resources for further biological and evolutionary studies,as well as for rapid improvement in growth-related traits.展开更多
Intron retention in aging and Alzheimer's disease (AD): AD is an age-related neurodegenerative disorder with pathological accumulation of amyloid plaque (Masters et al., 2015), which can be classified into familia...Intron retention in aging and Alzheimer's disease (AD): AD is an age-related neurodegenerative disorder with pathological accumulation of amyloid plaque (Masters et al., 2015), which can be classified into familial and sporadic form. In familial AD, mutations in genes encoding either amyloid precursor protein or presenilin (PS1 and PS2) cause overproduction of amyloid-42 molecules and early onset of dementia.展开更多
An （AC）n-microsatellite-enriched library for Larimichthys crocea was constructed in this study. Primers for fifty simple sequence repeat （SSR） loci were synthesized and genotyped on 30 L. crocea individuals from G...An （AC）n-microsatellite-enriched library for Larimichthys crocea was constructed in this study. Primers for fifty simple sequence repeat （SSR） loci were synthesized and genotyped on 30 L. crocea individuals from Guanjingyang wild population （WP） in Fujian Province and 38 individuals from Ningbo cultured population （CP） in Zhejiang Province. Only 21 loci were successfully amplified and polymorphic in two populations. In WP, the observed heterozygosity （Ho） ranged from 0.233 to 0.900 and the expected heterozygosity （HE） ranged from 0.326 to 0.893, with an average of 7.8 alleles/locus, the polymorphism information content （PIC） ranged from 0.283 to 0.866 （mean 0.731）. In CP, the Ho ranged from 0.189 to 0.892 and the HE ranged from 0.333 to 0.800, with an average of 4.4 alleles/locus. The probability test showed significant departures from HWE in 9 and 2 of the 21 loci in WP and in CP, respectively. Deficiency of heterozygotes at four loci showed the presence of null alleles （P 〈0.01）. The PIC of 20 microsatellite loci in WP were greater than 0.50. Overall, these novel markers are potentially useful for the study of population genetics, construction of genetic linkage and quantitative trait loci maps in large yellow croaker.展开更多
Tylorrhynchus heterochaetus is a widespread benthic polychaete worm found in coastal brackish waters of the west Pacific.It has high ecological and economic value as a biomarker of water quality and as a high-quality ...Tylorrhynchus heterochaetus is a widespread benthic polychaete worm found in coastal brackish waters of the west Pacific.It has high ecological and economic value as a biomarker of water quality and as a high-quality feed in aquaculture and fisheries and is considered a delicacy in some areas of Asia.However,it has experienced a marked reduction in recent years due to overexploitation as well as changes in the environment and climate.Here,to comprehensively understand its genetic background and thus provide insights for better conservation and utilization of this species,we assessed the genetic variability and demographic history of T.heterochaetus individuals sampled from eight locations along the coasts of southeast China and north Vietnam based on mitochondrial cytochrome c oxidase I(COI)sequences.We observed high haplotype diversity(Hd),with an average of 0.926,but relatively low nucleotide diversity(π),with a mean of 0.032 across all samples.A total of 94 polymorphic sites and 85 haplotypes were identified among 320 individuals.The pairwise genetic distances among haplotypes ranged from 0.001 to 0.067,with the high intraspecific divergence possibly reflecting geographic isolation and gene pool fragmentation.Significant genetic structures were revealed among the studied locations;specifically,the eight locations could be treated as six genetically different populations based on pairwiseΦST results(0.026–0.951,P<0.01).A significant pattern of isolation-by-distance was detected between the genetic and geographic distances(r=0.873,P=0.001).Three geographic lineages were defined based on phylogenetic tree and network analyses of COI haplotypes.AMOVA results indicated that genetic variations mainly occurred among the three lineages(89.96%).Tests of neutrality and mismatch distribution suggested that T.heterochaetus underwent recent population expansion.These results provide the first report on the genetic status of T.heterochaetus and will be valuable for the management of genetic resources and better understanding of the ecology and evolution in this species.展开更多
Polycomb repressive complex 2(PRC2)contributes to catalyze the methylation of histone H3 at lysine 27 and plays vital roles in transcriptional silencing and growth development in various organisms.In Magnaporthe oryza...Polycomb repressive complex 2(PRC2)contributes to catalyze the methylation of histone H3 at lysine 27 and plays vital roles in transcriptional silencing and growth development in various organisms.In Magnaporthe oryzae,histone H3K27 is found to associate with altered transcription of in planta induced genes.However,it is still unknown whether and how H3K27me3 modification is involved in pathogenicity to rice and stress response.In this study,we found that core subunits of PRC2,Kmt6-Suz12-Eed,were required for fungal pathogenicity to rice in M.oryzae.Kmt6-Suz12-Eed localized in the nuclei and was necessary for the establishment of H3K27me3 modification.With ChIP-seq analysis,9.0%of genome regions enriched with H3K27me3 occupancy,which corresponded to 1033 genes in M.oryzae.Furthermore,deletion of Kmt6,Suz12 or Eed altered genome-wide transcriptional expression,while the de-repression genes in theΔkmt6 strain were highly associated with H3K27me3 occupancy.Notably,plenty of genes which encode effectors and secreted enzymes,secondary metabolite synthesis genes,and cell wall stress-responsive genes were directly occupied with H3K27me3 modification and de-repression in theΔkmt6 strain.These results elaborately explained how PRC2 was required for pathogenicity,which is closely related to effector modulated host immunity and host environment adaption.展开更多
Dear Editor,Coxsackievirus A16(CA16)and enterovirus A71(EV-A71)are the main causative agents of hand foot and mouth disease(HFMD)(Alexander et al.,1994).Besides HFMD,EV-A71 infection in young children can lead to a sp...Dear Editor,Coxsackievirus A16(CA16)and enterovirus A71(EV-A71)are the main causative agents of hand foot and mouth disease(HFMD)(Alexander et al.,1994).Besides HFMD,EV-A71 infection in young children can lead to a spectrum of other clinical diseases and associated neurological complications and mortality(Melnick JL.,1996).In recent decades,EV-A71 infections have become a major public health concern throughout the world,following the frequent occurrence of epidemics and outbreaks of HFMD associated with neurological complications and high mortality in young children(Ishimaru et al.,1980;Tagaya et al.,1981;Chomnaitree et al.,1982;Samuda et al.,1987;Gilbert et al.,1988;Hayward et al.,1989;Lum et al.,1998;Chang et al.,1998;Liu et al.,2000;Yang et al.,2011;Zeng et al.,2012).展开更多
Precise regulation of stem cell self-renewal versus differentiation is important for the maintenance of tissue ho- meostasis. Early loss of stem cell activity results in premature ageing, while excess stem cell activi...Precise regulation of stem cell self-renewal versus differentiation is important for the maintenance of tissue ho- meostasis. Early loss of stem cell activity results in premature ageing, while excess stem cell activity leads to over- proliferation and cancer initiation （Fuchs et al., 2004; Scadden, 2006; Jones and Wagers, 2008; Morrison and Spradling, 2008）. Thus, understanding the mechanism con- trolling stem cell self-renewal and differentiation is critical for development of potential clinic therapy in the future.展开更多
Orchids make up one of the largest families of flowering plants(Orchidaceae) with a variety of ecological habitats and broad economic impact for their ornamental and medicinal values in the world.Sexual hybridization ...Orchids make up one of the largest families of flowering plants(Orchidaceae) with a variety of ecological habitats and broad economic impact for their ornamental and medicinal values in the world.Sexual hybridization followed by the selection of attractive traits in progenies is a classical but dominant method for breeding new and improved orchid varieties. This method is typically time-consuming as most orchid genera possess a long vegetative phase that could last from one year to many years(Yu and Goh, 2001). Thus, the protracted breeding period so far remains a bottleneck for the rapid production of new orchid varieties to satisfy consumer appetites for desirable traits.展开更多
The presented study aims to extend the knowledge of toxicological profile of rare earth elements salts(REEs).The basal toxicity test performed comprised assessment of cytotoxicity(3 T3 Balb/c Neutral Red Uptake Test)t...The presented study aims to extend the knowledge of toxicological profile of rare earth elements salts(REEs).The basal toxicity test performed comprised assessment of cytotoxicity(3 T3 Balb/c Neutral Red Uptake Test)that allows for calculation of LD50(rats)on the basis of the concentration which leads to a50%reduction in cell growth(IC50).Environmental toxicity was addressed by the Tubifex tubifex(T.t.)express test.The in vitro skin irritation(OECD TG 439)and skin corrosion tests(OECD TG 431)utilizing the 3 D in vitro reconstructed human epidermal model EpiDerm(MatTek IVSL,SK)were used for assessment of skin irritation and corrosion potential hazard of REEs.Mutagenic effects were determined using the bacterial reverse mutation assay(Ames Test)on 5 Salmonella typhimurium strains with and without metabolic activation(OECD TG 471).Endocrine disruption was evaluated by means of a yeastbased assay YES/YAS(Xenometrix,CH).Skin sensitization was assessed using the LuSens assay,based on a genetically modified human keratinocyte cell line(OECD TG 442 D).The tested REEs have no potential of mutagenicity or skin sensitization,exhibit very weak endocrine disruption potential and only exceptional local irritation/corrosion effects for thulium(Ⅲ)chloride anhydrous,but have acute and chronic toxic effects on the aquatic environment.展开更多
Rice line 1892S is an elite thermo-sensitive genic male sterile(TGMS)line for two-line hybrid rice production.However,1892S is susceptible to rice blast,bacterial blight and submergence.Here we reported the introducti...Rice line 1892S is an elite thermo-sensitive genic male sterile(TGMS)line for two-line hybrid rice production.However,1892S is susceptible to rice blast,bacterial blight and submergence.Here we reported the introduction of blast resistance(R)gene Pi9,bacterial blight R gene Xa21 and submergence tolerance gene Sub1A into 1892S genetic background through backcrossing and marker-assisted selection.The improved TGMS line 31892S and its hybrids conferred disease resistance to rice blast and bacterial blight,and showed submergence tolerance for over 14 d without significant loss of viability.The sterility-fertility conversion of 31892S was similar to that of 1892S.31892S and its derived hybrid rice had similar agronomic traits and grain quality with 1892S and the control hybrid rice,respectively.The newly developed 31892S provided an improved TGMS line for two-line hybrid rice production with disease resistance to rice blast and bacterial blight,and submergence tolerance with no yield penalty or change in grain quality.展开更多
基金supported by grants from the National Natural Science Foundation of China(No.31271582)Temasek Life Sciences Laboratory and Singapore Millennium FoundationBeijing Municipal Commission of Education(No.010135336400)
文摘Tissue homeostasis, accomplished through the self-renewai and differentiation of resident stem cells, is critical for the maintenance of adult tissues throughout an animal＇s lifetime, Adult Drosophila Malpighian tubules （MTs or fly kidney） are maintained by renal and nephric stem cells （RNSCs） via self-renewing divisions, however, it is unclear how RNSC proliferation and differentiation are regulated. Here we show that EGFR/MAPK signaling is dispensable for RNSC maintenance, but required for RNSC proliferation in vivo. Inacti- vation of the EGFR/MAPK pathway blocks or greatly retards RNSC cell cycle progression; conversely, over-activation of EGFR/MAPK signaling results in RNSC over-proliferation and disrupts the normal differentiation of renablasts （RBs）, the immediate daughters of RNSC divisions. Our data further suggest that EGFR/MAPK signaling functions independently of JAK/STAT signaling and that dMyc and CycE partially mediate EGFR/MAPK signaling in MTs. Together, our data suggest a principal role of EGFR/MAPK signaling in regulating RNSC proliferation, which may provide important clues for understanding mammalian kidney repair and regeneration following injury.
基金This study was supported by China Postdoctoral Science Foundation(20040350377)National Natural Science Foundation of China(30400294).
文摘Laboratory studies were conducted to evaluate the risk of Phytophthora capsici developing resistance to two morphlines, dimethomorph and flumorph. Metalaxyl, the well-known high risk of resistance fungicides, was used as reference fungicide. Resistant mutants for the three fungicides were isolated by treating mycelium with ultraviolet radiation. Metalaxyl-resistant mutants were obtained with high frequency and exhibited high level of resistance with factors more than 100 folds, while mutation frequency for dimethomorph-resistance was relatively low and the resistance factors ranged from 3.0 to 13.9 folds. Most dimethomorph-resistant mutants decreased in hyphal growth rate and the spoulation ability, which have a large impact upon the epidemic development of dimethomorph-resistant populations. These results suggested that the risk of resistant pathogen population was much lower for dimethomorph than for metalaxyl. Both the frequency of developing resistance and level of resistance （resistance factors = 1.8-14.6） to dimethomorph were similar to those of its structure analogue flumorh. Moreover, the cross-resistance were found between them, which suggested the risks of developing resistance to dimethomorph and flumorph in the pathogen were very closely related. As P. capsici can potentially develop resistance to dimethomorph and flumorph, and oomycetes usually have the high risk to develop resistance to fungicides, appropriate management against resistance development should be taken.
基金supported by core funding provided by Temasek Life Sciences Laboratory(to CTO)。
文摘Apolipoprotein E has diverse functions in neurons:Apolipoprotein E(ApoE)is a glycoprotein that primarily regulates lipid metabolism and transport in the central nervous system.There are three predominant human ApoE protein isoforms with cysteine and arginine substitutions at amino acid positions 112 and 158 that impact their lipidation and related functions(Flowers and Rebeck,2020).ApoE2 is characterized by Cys112 and Cys158,ApoE3 by Cys112 and Arg158,whereas ApoE4 contains Arg112 and Arg158.
基金financially supported by internal funding from the Temasek Life Sciences Laboratory,Singapore.
文摘Asian seabass(Lates calcarifer)is becoming an important species for aquaculture.However,the Asian seabass aquaculture industry faces a significant challenge of disease outbreaks that can jeopardize fish health and production.This review delves into the major diseases affecting Asian seabass aquaculture and explores their causes,symptoms,and management approaches.We focused on the key pathogens responsible for these outbreaks,the environmental factors contributing to disease susceptibility,and the latest advancements in disease prevention and management.By addressing these critical aspects,this review addresses the needs of aquaculturists,researchers,and policymakers with the knowledge required to promote resilient and sustainable Asian seabass farming.We aim to shed light on the challenges posed by disease while highlighting innovative strategies that offer promise for the future of this thriving industry.This comprehensive examination serves as a valuable resource for those invested in ensuring the health and vitality of Asian seabass,securing a consistent supply to meet the demands of global seafood markets.
基金supported by the National Key R&D Program of China(2023YFD1200704)the intramural research support from Temasek Life Sciences Laboratory.
文摘On top of genetic information,organisms have evolved complex and sophisticated epigenetic regulation to adjust gene expression in response to developmental and environmental signals.Key epigenetic mechanisms include DNA methylation,histone modifications and variants,chromatin remodeling,and chemical modifications of RNAs.Epigenetic control of environmental responses is particularly important for plants,which are sessile and unable to move away from adverse environments.Besides enabling plants to rapidly respond to environmental stresses,some stress-induced epigenetic changes can be maintained,providing plants with a pre-adapted state to recurring stresses.Understanding these epigenetic mechanisms offers valuable insights for developing crop varieties with enhanced stress tolerance.Here,we focus on abiotic stresses and summarize recent progress in characterizing stress-induced epigenetic changes and their regulatory mechanisms and roles in plant abiotic stress resistance.
文摘Influenza A viruses are important human pathogens causing periodic pandemic threats. Nonstructural protein 1 （NS1） protein of influenza A virus （NS1A） shields the virus against host defense. Here, we report the crystal structure of NS1A RNA-binding domain （RBD） bound to a double-stranded RNA （dsRNA） at 1.7A. NS1A RBD forms a homodimer to recognize the major groove of A-form dsRNA in a length-independent mode by its conserved concave surface formed by dimeric anti-parallel a-helices, dsRNA is anchored by a pair of invariable arginines （Arg38） from both monomers by extensive hydrogen bonds. In accordance with the structural observation, isothermal titration calorimetry assay shows that the unique Arg38-Arg38 pair and two Arg35-Arg46 pairs are crucial for dsRNA binding, and that Ser42 and Thr49 are also important for dsRNA binding. Agrobacterium co-infiltration assay further supports that the unique Arg38 pair plays important roles in dsRNA binding in vivo.
基金supported by the National Natural Science Foundation of China(No.30670018,30621005)
文摘Microbial oxidation and reduction of iron and sulfur are important parts of biogeochemical cycles in acidic environments such as geothermal solfataric regions. Species of Acidithiobacillus and Leptospirillum are the common ferrous-iron and sulfur oxidizers from such environments. This study focused on the Tengchong sofataric region, located in Yunnan Province, Southwest China. Based on cultivation, 9 strains that grow on ferrous-iron and sulfuric compounds were obtained. Analysis of 16S rRNA genes of the 9 strains indicated that they were affiliated to AcidithiobaciUus, Alicyclobacillus, Sulfobacillus, Leptospirillum and Acidiphilium. Physiological and phylogenetic studies indicated that two strains （TC-34 and TC-71） might represent two novel members of Alicyclobacillus. Strain TC-34 and TC-71 showed 94.8%-97.1% 16S rRNA gene identities to other species of Alicyclobacillus. Different from the previously described Alicyclobacillus species, strains TC-34 and TC-71 were mesophilic and their cellular fatty acids do not contain w-cyclic fatty acids. Strain TC-71 was obligately dependent on ferrous-iron for growth. It was concluded that the ferrous-iron oxidizers were diversified and Alicyclobacillus species were proposed to take part in biochemical geocycling of iron in the Tengchong solfataric region.
基金supported by the National Natural Science Foundation of China,No.81400922(to DMW),81571084the Natural Science Foundation of Fujian Province of China,No.2018J01813(to DMW)the College of Life Sciences of Fujian Normal University of China,No.FZSKG2018016(to DMW)
文摘Adrenomedullin,a peptide with multiple physiological functions in nervous system injury and disease,has aroused the interest of researchers.This review summarizes the role of adrenomedullin in neuropathological disorders,including pathological pain,brain injury and nerve regeneration,and their treatment.As a newly characterized pronociceptive mediator,adrenomedullin has been shown to act as an upstream factor in the transmission of noxious information for various types of pathological pain including acute and chronic inflammatory pain,cancer pain,neuropathic pain induced by spinal nerve injury and diabetic neuropathy.Initiation of glia-neuron signaling networks in the peripheral and central nervous system by adrenomedullin is involved in the formation and maintenance of morphine tolerance.Adrenomedullin has been shown to exert a facilitated or neuroprotective effect against brain injury including hemorrhagic or ischemic stroke and traumatic brain injury.Additionally,adrenomedullin can serve as a regulator to promote nerve regeneration in pathological conditions.Therefore,adrenomedullin is an important participant in nervous system diseases.
基金supported financially by the internal research funding from Temasek Life Sciences Laboratorythe Huangarian Scientific Research Fund(OTKAPD79177)
文摘Microsatellites have been widely used in studies on population genetics, ecology and evolutionary biology. However, microsatellites are not always available for the species to be studied and their isolation could be time-consuming. In order to save time and effort researchers often rely on cross-species amplification. We revealed a new problem of microsatellite cross-species amplification in addition to size homoplasy by analyzing the sequences of electromorphs from seven catfish species belonging to three different families （Clariidae, Heteropneustidae and Pimelodidae）. A total of 50 different electromorphs were amplified from the seven catfish species by using primers for 4 microsatellite loci isolated from the species Clarias batrachus. Two hundred and forty PCR-products representing all 50 electromorphs were sequenced and analyzed. Primers for two loci amplified specific products from orthologous loci in all species tested, whereas primers for the other two loci produced specific and polymorphic bands from some non-orthologous loci, even in closely related non-source species. Size homoplasy within the source species was not obvious, whereas extensive size homoplasy across species were detected at three loci, but not at the fourth one. These data suggest that amplification of products from non-orthologous loci and appearance of size homoplasy by cross-amplification are locus dependent, and do not reflect phylogenetic relationship. Amplification of non-orthologous loci and appearance of size homoplasy will lead to obvious complications in phylogenetie interference, population genetic and evolutionary studies. Therefore, we propose that sequence analysis of cross-amplification products should be conducted prior to application of cross-species amplification of microsatellites.
基金supported by the Internal Funds of the Temasek Life Sciences Laboratory(5020)。
文摘Understanding the genetic basis of phenotypes is of importance in evolutionary biology and for genetic improvement of economically valuable animals.The giant phenotype of the fighting fish,Betta splendens,provides a unique opportunity to explore the genetic architecture of overgrowth in body size.As such,we re-sequenced and analyzed the genomes of 54 fighting fish.Genome-wide FST and selective sweep analyses using 3582429 DNA variants revealed three genomic regions at chr1,chr9,and chr11 that were associated with the giant phenotype.With a total length of~3.5 Mb,these regions showed high divergence between the giant and non-giant bettas.In contrast,no signature of selection was detected in the wild-type fish.Transcriptome analysis of brain and muscle samples from giant and normal bettas identified 14 candidate genes that were likely responsible for the giant phenotype.Overall,our data provide novel insights into the genetic basis of body size variation.The genome sequences,transcriptome sequences,DNA sequence variants,and candidate genes for body size provide valuable resources for further biological and evolutionary studies,as well as for rapid improvement in growth-related traits.
基金supported by core funding provided by Temasek Life Sciences Laboratory
文摘Intron retention in aging and Alzheimer's disease (AD): AD is an age-related neurodegenerative disorder with pathological accumulation of amyloid plaque (Masters et al., 2015), which can be classified into familial and sporadic form. In familial AD, mutations in genes encoding either amyloid precursor protein or presenilin (PS1 and PS2) cause overproduction of amyloid-42 molecules and early onset of dementia.
基金The Special Fund for Agro-Scientific Research in the Public Interest under contract No.200903046-5the National High Technology Research and Development Program of China(863program)under contract No.2006AA10A405+1 种基金the National Natural Science Foundation of China under contract No.30771663the Foundation for Innovation Research Team of Jimei University,China under contract No.2006A001
文摘An （AC）n-microsatellite-enriched library for Larimichthys crocea was constructed in this study. Primers for fifty simple sequence repeat （SSR） loci were synthesized and genotyped on 30 L. crocea individuals from Guanjingyang wild population （WP） in Fujian Province and 38 individuals from Ningbo cultured population （CP） in Zhejiang Province. Only 21 loci were successfully amplified and polymorphic in two populations. In WP, the observed heterozygosity （Ho） ranged from 0.233 to 0.900 and the expected heterozygosity （HE） ranged from 0.326 to 0.893, with an average of 7.8 alleles/locus, the polymorphism information content （PIC） ranged from 0.283 to 0.866 （mean 0.731）. In CP, the Ho ranged from 0.189 to 0.892 and the HE ranged from 0.333 to 0.800, with an average of 4.4 alleles/locus. The probability test showed significant departures from HWE in 9 and 2 of the 21 loci in WP and in CP, respectively. Deficiency of heterozygotes at four loci showed the presence of null alleles （P 〈0.01）. The PIC of 20 microsatellite loci in WP were greater than 0.50. Overall, these novel markers are potentially useful for the study of population genetics, construction of genetic linkage and quantitative trait loci maps in large yellow croaker.
基金supported by the IndustryAcademic Research Cooperation Program of Academician Workstation of Guangdong Province(2013B090400017)Natural Science Foundation of Guangdong Province(2016A030307036)Yangfan Innovative&Entrepreneurial Research Team Project for Guangdong Province(201312H10)
文摘Tylorrhynchus heterochaetus is a widespread benthic polychaete worm found in coastal brackish waters of the west Pacific.It has high ecological and economic value as a biomarker of water quality and as a high-quality feed in aquaculture and fisheries and is considered a delicacy in some areas of Asia.However,it has experienced a marked reduction in recent years due to overexploitation as well as changes in the environment and climate.Here,to comprehensively understand its genetic background and thus provide insights for better conservation and utilization of this species,we assessed the genetic variability and demographic history of T.heterochaetus individuals sampled from eight locations along the coasts of southeast China and north Vietnam based on mitochondrial cytochrome c oxidase I(COI)sequences.We observed high haplotype diversity(Hd),with an average of 0.926,but relatively low nucleotide diversity(π),with a mean of 0.032 across all samples.A total of 94 polymorphic sites and 85 haplotypes were identified among 320 individuals.The pairwise genetic distances among haplotypes ranged from 0.001 to 0.067,with the high intraspecific divergence possibly reflecting geographic isolation and gene pool fragmentation.Significant genetic structures were revealed among the studied locations;specifically,the eight locations could be treated as six genetically different populations based on pairwiseΦST results(0.026–0.951,P<0.01).A significant pattern of isolation-by-distance was detected between the genetic and geographic distances(r=0.873,P=0.001).Three geographic lineages were defined based on phylogenetic tree and network analyses of COI haplotypes.AMOVA results indicated that genetic variations mainly occurred among the three lineages(89.96%).Tests of neutrality and mismatch distribution suggested that T.heterochaetus underwent recent population expansion.These results provide the first report on the genetic status of T.heterochaetus and will be valuable for the management of genetic resources and better understanding of the ecology and evolution in this species.
基金the National Natural Science Foundation of China(Grant Nos.32170192 and 32000103)Zhejiang Science and Technology Major Program on Agricultural New Variety Breeding(Grant No.2021C02064)+1 种基金Key Research and Development Project of China National Rice Research Institute(Grant No.CNRRI-2020-04)the Chinese Academy of Agricultural Sciences under the‘Elite Youth’Program and the Agricultural Sciences and Technologies Innovation Program.
文摘Polycomb repressive complex 2(PRC2)contributes to catalyze the methylation of histone H3 at lysine 27 and plays vital roles in transcriptional silencing and growth development in various organisms.In Magnaporthe oryzae,histone H3K27 is found to associate with altered transcription of in planta induced genes.However,it is still unknown whether and how H3K27me3 modification is involved in pathogenicity to rice and stress response.In this study,we found that core subunits of PRC2,Kmt6-Suz12-Eed,were required for fungal pathogenicity to rice in M.oryzae.Kmt6-Suz12-Eed localized in the nuclei and was necessary for the establishment of H3K27me3 modification.With ChIP-seq analysis,9.0%of genome regions enriched with H3K27me3 occupancy,which corresponded to 1033 genes in M.oryzae.Furthermore,deletion of Kmt6,Suz12 or Eed altered genome-wide transcriptional expression,while the de-repression genes in theΔkmt6 strain were highly associated with H3K27me3 occupancy.Notably,plenty of genes which encode effectors and secreted enzymes,secondary metabolite synthesis genes,and cell wall stress-responsive genes were directly occupied with H3K27me3 modification and de-repression in theΔkmt6 strain.These results elaborately explained how PRC2 was required for pathogenicity,which is closely related to effector modulated host immunity and host environment adaption.
基金funded by the Temasek Lifesciences Laboratory core funding
文摘Dear Editor,Coxsackievirus A16(CA16)and enterovirus A71(EV-A71)are the main causative agents of hand foot and mouth disease(HFMD)(Alexander et al.,1994).Besides HFMD,EV-A71 infection in young children can lead to a spectrum of other clinical diseases and associated neurological complications and mortality(Melnick JL.,1996).In recent decades,EV-A71 infections have become a major public health concern throughout the world,following the frequent occurrence of epidemics and outbreaks of HFMD associated with neurological complications and high mortality in young children(Ishimaru et al.,1980;Tagaya et al.,1981;Chomnaitree et al.,1982;Samuda et al.,1987;Gilbert et al.,1988;Hayward et al.,1989;Lum et al.,1998;Chang et al.,1998;Liu et al.,2000;Yang et al.,2011;Zeng et al.,2012).
基金supported by the grants from the National Natural Science Foundation of China(Nos.31271582 and 31471384)Temasek Life Sciences Laboratory and Singapore Millennium FoundationBeijing Municipal Commission of Education (No.010135336400)
文摘Precise regulation of stem cell self-renewal versus differentiation is important for the maintenance of tissue ho- meostasis. Early loss of stem cell activity results in premature ageing, while excess stem cell activity leads to over- proliferation and cancer initiation （Fuchs et al., 2004; Scadden, 2006; Jones and Wagers, 2008; Morrison and Spradling, 2008）. Thus, understanding the mechanism con- trolling stem cell self-renewal and differentiation is critical for development of potential clinic therapy in the future.
基金supported by the Singapore National Research Foundation Competitive Research Programme(NRF-CRP22-2019-0001)the intramural research support from National University of Singapore and Temasek Life Sciences Laboratory。
文摘Orchids make up one of the largest families of flowering plants(Orchidaceae) with a variety of ecological habitats and broad economic impact for their ornamental and medicinal values in the world.Sexual hybridization followed by the selection of attractive traits in progenies is a classical but dominant method for breeding new and improved orchid varieties. This method is typically time-consuming as most orchid genera possess a long vegetative phase that could last from one year to many years(Yu and Goh, 2001). Thus, the protracted breeding period so far remains a bottleneck for the rapid production of new orchid varieties to satisfy consumer appetites for desirable traits.
基金the ERDF/ESF project“International Competitiveness of NIPH in Research,Development and Education in Alternative Toxicological Methods”(CZ.02.1.01/0.0/0.0/16019/0000860)by Ministry of Health,Czech Republic-Conceptual Development of Research Organization(National Institute of Public Health-NIPH,75010330)。
文摘The presented study aims to extend the knowledge of toxicological profile of rare earth elements salts(REEs).The basal toxicity test performed comprised assessment of cytotoxicity(3 T3 Balb/c Neutral Red Uptake Test)that allows for calculation of LD50(rats)on the basis of the concentration which leads to a50%reduction in cell growth(IC50).Environmental toxicity was addressed by the Tubifex tubifex(T.t.)express test.The in vitro skin irritation(OECD TG 439)and skin corrosion tests(OECD TG 431)utilizing the 3 D in vitro reconstructed human epidermal model EpiDerm(MatTek IVSL,SK)were used for assessment of skin irritation and corrosion potential hazard of REEs.Mutagenic effects were determined using the bacterial reverse mutation assay(Ames Test)on 5 Salmonella typhimurium strains with and without metabolic activation(OECD TG 471).Endocrine disruption was evaluated by means of a yeastbased assay YES/YAS(Xenometrix,CH).Skin sensitization was assessed using the LuSens assay,based on a genetically modified human keratinocyte cell line(OECD TG 442 D).The tested REEs have no potential of mutagenicity or skin sensitization,exhibit very weak endocrine disruption potential and only exceptional local irritation/corrosion effects for thulium(Ⅲ)chloride anhydrous,but have acute and chronic toxic effects on the aquatic environment.
文摘Rice line 1892S is an elite thermo-sensitive genic male sterile(TGMS)line for two-line hybrid rice production.However,1892S is susceptible to rice blast,bacterial blight and submergence.Here we reported the introduction of blast resistance(R)gene Pi9,bacterial blight R gene Xa21 and submergence tolerance gene Sub1A into 1892S genetic background through backcrossing and marker-assisted selection.The improved TGMS line 31892S and its hybrids conferred disease resistance to rice blast and bacterial blight,and showed submergence tolerance for over 14 d without significant loss of viability.The sterility-fertility conversion of 31892S was similar to that of 1892S.31892S and its derived hybrid rice had similar agronomic traits and grain quality with 1892S and the control hybrid rice,respectively.The newly developed 31892S provided an improved TGMS line for two-line hybrid rice production with disease resistance to rice blast and bacterial blight,and submergence tolerance with no yield penalty or change in grain quality.
