Triploid Pacific oysters(Crassostrea gigas)are highly valued due to their rapid growth and low fertility,making them commercially desirable.However,these reproductive characteristics also hinder their capability to pr...Triploid Pacific oysters(Crassostrea gigas)are highly valued due to their rapid growth and low fertility,making them commercially desirable.However,these reproductive characteristics also hinder their capability to produce subsequent generations.Large-scale triploid production relies on crossing female diploid and male tetraploid oysters.This study assessed the effects of shell morphology on body weight and fecundity in diploid and tetraploid oysters using multiple regression and path analysis.Substantial correlations were found between shell morphology and body weight traits,as well as between shell morphology and fecundity traits across diploid and tetraploid oysters.Path analysis revealed that shell morphology traits significantly impact body weight and fecundity in both diploids and tetraploids.Among these traits,shell height had the strongest direct effect on body weight and fecundity,while shell height and shell length notably contributed through indirect effects.These findings highlight the importance of shell height in shaping body weight and fecundity in diploid and tetraploid Pacific oysters,indicating that selective breeding,with a particular focus on enhancing shell height,could simultaneously promote increases in shell length.展开更多
Crassostrea gigas has good taste and high nutritional value;however,there are few assessments of comprehensive and panoramic analyses of the nutritional quality of the northern oyster.To study the nutritional characte...Crassostrea gigas has good taste and high nutritional value;however,there are few assessments of comprehensive and panoramic analyses of the nutritional quality of the northern oyster.To study the nutritional characteristics of C.gigas from different sources(ploidy,region,size,and culture mode),C.gigas from various ploidy(diploid and triploid),regions(Rushan,Off-site fattening,and Rongcheng),sizes(small,medium,and large)and culture modes(nearshore and offshore)were selected for comparative analyses.The nutritional components(moisture,protein,fat,and mineral),flavor substances(taste amino acids,nucleotides,and succinic acid),and functional indices(eicosapentaenoic acid(EPA),docosahexaenoic acid(DHA),and taurine)of C.gigas were determined.Principal component analysis(PCA)was used to comprehensively evaluate the oysters and investigate the variations in nutritional quality.The PCA results indicate that protein,essential fatty acids,selenium,zinc,taste amino acids,taurine,EPA,and DHA were core components contributing to 82.25%of the cumulative variance,providing a more comprehensive reflection of the nutrient composition of C.gigas.The extensive quality rankings for the C.gigas were as follows:diploid>triploid,Rushan>fattening>Rongcheng,medium>large>small,and offshore>nearshore.The score rank revealed that diploid oysters of medium-size from Rushan demonstrated superior nutritional quality compared to other tested samples.This is the first comprehensive and systematic investigation of C.gigas in northern China to reveal the feature of nutrients,flavor,and functional components.The study provided data support for the culture,consumption,processing,research,and nutritional quality improvement of oyster industry.展开更多
Prostatic carcinoma(PCa)has become one of the most common cancers among men worldwide,with both incidence and mortality rates steadily rising.Although current treatments are effective in the early stages of PCa,many c...Prostatic carcinoma(PCa)has become one of the most common cancers among men worldwide,with both incidence and mortality rates steadily rising.Although current treatments are effective in the early stages of PCa,many cases eventually progress to castration-resistant prostate cancer(CRPC),and led to treatment failure.To develop new therapeutic strategies to ameliorate the survival of PCa patients then has pressed the need on medicinal researchers.Of traditional Chinese medicinal herbs,Angelica gigas Naka(AGN),and its major pyranocoumarins were broadly reported on the effect of anti-PCa.However,existing reviews mainly focus on decursin(D),decursinol angelate(DA),and decursinol(DOH),without fully exploring other coumarins in AGN.Moreover,most reviews discuss general anticancer effects,with limited emphasis on PCa specifically.This review made a comprehensive summary of the coumarin components of AGN,and depicted the anti-PCa effects and mechanisms,giving a solid research support for drug discovery and development.This review also featured pharmacokinetic advantages and therapeutic potential of DOH,in order to suggest possibilities to overcome the in vivo transformation limitations of D and DA,and shed light on CRPC treatment.We also recommend future studies focus on more in vivo evidence,safety and toxicity evaluation,and clinical validation in humans.展开更多
A crossbreeding program was established in 2019 to address the declining Crassostrea gigas harvests caused by Pacific Oyster Mortality Syndrome(POMS).As a part of the program,this study was performed to estimate the g...A crossbreeding program was established in 2019 to address the declining Crassostrea gigas harvests caused by Pacific Oyster Mortality Syndrome(POMS).As a part of the program,this study was performed to estimate the genetic structure underlying phenotypic variation.Fifteen complete diallel crossings of C.gigas and C.angulata,comprising 60 full-sib families,were used to evaluate the general combining ability(GCA)and specific combining ability(SCA),as well as genotype and environment interactions for shell height(SH),summer survival(SS),and thermal tolerance(TT)of reciprocal hybrids GA(C.gigas♀×C.angulata♂)and AG(C.angulata♀×C.gigas♂)grown in Rongcheng and Rushan,Shandong Province,China.The results suggested that heterosis of the reciprocal hybrids was evident for SH,SS,and TT.The hybrid GA had larger heterosis than AG in both testing environments,and can be a potential donor in the breeding program.The male C.gigas had better GCA for SH in Rongcheng,whereas male C.angulata was a good general combiner for SS and TT in both Rongcheng and Rushan.The estimate of SCA was much higher than GCA for SH and lower than GCA for TT.To harness both additive and non-additive genetic effects,combination breed-ing could be taken to develop hybrid varieties possessing both thermal tolerance and fast-growing traits.The positive correlations between SH and TT suggested that these traits could be improved simultaneously.The significant G×E interactions demonstrated the importance to undertake site-specific breeding programs in different environments.Overall,this study can provide essential information for developing crossbreeding strategies for the oyster farming industry.展开更多
Crassostrea gigas is distinguished by its robust fertility,adaptability to various environmental conditions,and rich nutritional profile,which render it a cornerstone of the global shellfish market.Tetraploid oysters,...Crassostrea gigas is distinguished by its robust fertility,adaptability to various environmental conditions,and rich nutritional profile,which render it a cornerstone of the global shellfish market.Tetraploid oysters,in particular,is a pivotal role within the oyster industry,however,their growth and survival characteristics need to be improved.This study aimed to assess the viability of enhancing the growth and survival characteristics of tetraploid C.gigas through genetic selection.This was achieved by investigating the heritability and genetic correlation of growth and survival at various stages of C.gigas development.Genetic parameters were assessed based on in-group correlations in 28 full-sib families during the larval stage(days 3,8,13,18,and 23 after fertilization).The heritability of larval shell height and shell length ranged from 0.50 to 0.71 and 0.44 to 0.71,respectively,and varied with age.The heritability of larval survival was 0.40–0.64,indicating that it is viable to enhancelarval survival through selection.The genetic correlation between the growth traits of larvae at different ages was highly positive(0.959–0.999),indicating that the selection of a single growth trait could cause the positive response of other growth traits.However,the genetic correlation between larval survival and growth traits was low,showing a significant negative correlation(-0.198–-0.293)at day 23 of age,suggesting thatselecting for enhanced survival in tetraploid C.gigas may result in a detrimental impact on growth traits.The results are helpful for future researches to evaluate the genetic parameters related to growth and survival traits in juvenile and adult stages of the tetraploid family of C.gigas,which can provide further guidance for the selection of tetraploid C.gigas.展开更多
Tetraploid oysters frequently exhibit growth and survival rates inferior to diploid and triploid oysters.Tetraploid Pacific oysters(Crassostrea gigas)are pivotal as broodstock in the triploid C.gigas industry.However,...Tetraploid oysters frequently exhibit growth and survival rates inferior to diploid and triploid oysters.Tetraploid Pacific oysters(Crassostrea gigas)are pivotal as broodstock in the triploid C.gigas industry.However,the high mortality of tetraploid C.gigas has occurred in production practice with the increasing temperature.The transcriptional patterns of high temperature-susceptible and-tolerant tetraploid C.gigas were compared in response to prolonged thermal treatment.The H was defined as oysters that have not been thermally treated.The susceptible and tolerant oysters after thermal treatment were designed as TS and TH,respectively.The survival rate of tetraploid C.gigas was low(6.33%±2.87%)after thermal treatment.A total of 5147,5250,and 433 differentially expressed genes(DEGs)were detected in TS vs.TH,TS vs.H,and TH vs.H groups,respectively.Functional enrichment analysis indicated that DEGs were notably enriched in various pathways,including the NF-kappa B signaling pathway,apoptosis,TNF signaling pathway,and arginine and proline metabolism,across both TS vs.TH and TS vs.H groups.Among the DEGs under thermal treatment in susceptible oysters,the translation regulation genes like eIF2a kinase 1,eIF2a kinase 3,MKNK1,and ATF-4 exhibited differential expressions.Susceptible oysters displayed a higher number of differentially expressed IAP genes compared to tolerant oysters,while the expression pattern of HSP genes differed between susceptible and tolerant oysters.This study underscores the contrasting response of susceptible and tolerant tetraploid C.gigas to thermal treatment,suggesting that high temperature-susceptible tetraploid C.gigas may be more responsive to rapid alterations in immune response and apoptosis compared to high temperature-tolerant tetraploid C.gigas.It is necessary to improve the high temperature tolerance of tetraploid C.gigas by selective breeding to promote the development of the triploid industry.展开更多
Recently,allotriploids from Pacific oysters(Crassostrea gigas)and Fujian oysters(C.angulata)have been grown for aquaculture.However,the viability of these allotriploids remains uncertain.In this study,two autotriploid...Recently,allotriploids from Pacific oysters(Crassostrea gigas)and Fujian oysters(C.angulata)have been grown for aquaculture.However,the viability of these allotriploids remains uncertain.In this study,two autotriploids,TGG(diploid C.gigas♀×tetraploid C.gigas♂)and TAA(diploid C.angulata♀×tetraploid C.angulata♂),and two allotriploids,TGA(diploid C.gigas♀×tetraploid C.angulata♂)and TAG(diploid C.angulata♀×tetraploid C.gigas♂),were studied to assess the heterosis in growth and survival at different temperatures and salinities.The results showed that during the larval stage,TAG exhibited increased heterosis in growth and survival when temperature rose.During the adult stage,the growth of TGA significantly outperformed other triploids at higher temperatures(23 and 28℃)and salinities(25 and 30).In contrast,TAG demonstrated the highest survival probability across all conditions except at salinity 25,where it equaled TAA after day 19.The highest oxygen consumption rates(OCR)of TGA and TAG were observed at 23 and 28℃,while the ammonia excretion rate(AER)of TAG was significantly higher than that of TGA at 23℃.These physiological parameters reflect the advantage of TAG in terms of survival.Notably,the temperature coefficient of allotriploids was higher than that of autotriploids in the range of 18–23℃.At 28℃,TAG showed the highest superoxide dismutase(SOD)and catalase(CAT)activities and the lowest malondialdehyde(MDA)content,showing its advantage when encountering high-temperature.展开更多
Triploid oysters are widely cultured due to their superior growth compared to diploids.However,differences in tempera-ture-salinity adaptation between di-and triploid oysters remain inconclusive.This study compared th...Triploid oysters are widely cultured due to their superior growth compared to diploids.However,differences in tempera-ture-salinity adaptation between di-and triploid oysters remain inconclusive.This study compared the survival rates,antioxidant en-zyme activities,and gene expressions in di-and triploid Pacific oyster Crassostrea gigas cultured in different temperatures(17,20,23,26,and 29℃)and salinities(18,22,26,30,and 34).Results showed that the optimum survival condition for both di-and triploids is 23℃/30.At 23℃,triploids exhibited significantly higher superoxide dismutase activity and lower heat shock protein 70(Hsp70)expression than diploids.At 29℃,triploids exhibited significantly higher survival rates than diploids.Across varying tem-peratures,triploids demonstrated significantly higher survival rates and antioxidant enzyme activities,along with lower malondialdehyde(MDA)levels and Hsp70 expression compared to diploids.The overall results demonstrate that triploids have a more robust antioxidant ca-pacity,reduced oxidative damage,and lower mortality than diploids under temperature treatments.Additionally,at a salinity of 18,triploids showed significantly higher catalase(CAT)level than diploids.Across varying salinities,triploids maintained lower MDA levels.These results suggest that triploids possess a stronger antioxidant defense under salinity treatments.In conclusion,triploid C.gigas demonstrates superior adaptation to diverse temperature and salinity conditions over diploids and are recommended for culture to improve oyster production.展开更多
As an important shellfish group,the oyster can induce severe allergic reactions.We aimed to identify and characterize the major allergen in Crassostrea gigas,and elucidate the molecular basis of its allergenicity and ...As an important shellfish group,the oyster can induce severe allergic reactions.We aimed to identify and characterize the major allergen in Crassostrea gigas,and elucidate the molecular basis of its allergenicity and cross-reactivity.The native and recombinant C.gigas-arginine kinase(AK)displayed significant immunoglobulin(Ig)G-and Ig E-binding activity.The Ig E-binding activity of C.gigas-AK could be reduced by thermal treatment and strong acidic and alkaline conditions.Besides,cross-reactivity of AK was demonstrated between shellfish species.Among seven epitope peptides identified here,P2 is responsible for the specificity of C.gigas-AK,while P3 is responsible for cross-reactions between mollusks and crustaceans.Furthermore,Glu98 and His31 in the light chain,Arg101,and Lys57 in the heavy chain are identified as key Ig E residues in recognizing epitopes.These findings provide new insights into the prevention and treatment of shellfish allergy and the development of hypoallergenic shellfish products.展开更多
The Pacific oyster(Crassostrea gigas)is a primary shellfish species for aquaculture around the world.However,the industry of Pacific oyster has been impaired by the mass summer mortality caused by environmental pertur...The Pacific oyster(Crassostrea gigas)is a primary shellfish species for aquaculture around the world.However,the industry of Pacific oyster has been impaired by the mass summer mortality caused by environmental perturbations,including hypoxia.Selective breeding of oysters with high hypoxia tolerance is a sustainable approach to prevent economic loss caused by hypoxia.In this study,we constructed 36 C.gigas families and executed the hypoxia stress experiment to estimate genetic parameters for hypoxia tolerance.The survival rate among 36 C.gigas families ranged from 0 to 53.33%,suggesting that high levels of phenotypic variation existed in the trait of hypoxia tolerance.Genetic parameters of hypoxia tolerance estimated by six statistical models showed a low to moderate heritability,ranging from 0.167 to 0.291.The Pearson and Spearman correlation coefficients among families estimated breeding values(EBVs)were high and positive,indicating that different models resulted in similar results in the estimation of breeding values.The phenotypic correlation between growth traits and hypoxia tolerance ranged from-0.030 to 0.061,while genetic correlation ranged from 0.110 to 0.285,implying that growth and hypoxia tolerance were independent traits.This work reported the first estimation of genetic parameters for hypoxia tolerance in C.gigas,and provided valuable information for the genetic improvement of hypoxia tolerance.展开更多
Oysters are of the most economically important bivalves worldwide.It has high nutritional value and is regarded as a good source of proteins,lipids,glycogen,and amino acids.C.gigas and C.angulata are allopatric congen...Oysters are of the most economically important bivalves worldwide.It has high nutritional value and is regarded as a good source of proteins,lipids,glycogen,and amino acids.C.gigas and C.angulata are allopatric congeneric dominant oysters that are widely cultivated in the northern and southern coast of China,and have shown remarkable differentiation in the nutritional content.Interspecific hybridization and backcross of the two species are effective ways to improve the nutritional quality of the oyster.Sixteen progenies were constructed based on a 4×4 diallel crosses among broodstock of C.gigas(G),C.angulata(A)and their hybrids GA(H)and AG(R).The glycogen,fatty acids,and amino acids performance of these progenies were evaluated in 22 months after fertilization.The glycogen content of AA was significantly lower than that of the other 15 progenies(P<0.05),while only the GH progeny was significantly higher than the GG(P<0.05),with a heterosis value of 21.06%.The backcross progenies GR exhibited significantly higher saturated fatty acids,eicosapentaenoic acid(EPA),and polyunsaturated fatty acids(PUFAs)content than those of GG(P<0.05),and did not show significant differences from AA.The AA showed significantly higher content of total amino acids(TAAs)than GG(P<0.05).The AH progeny displayed significantly higher taurine(Tau)content than GG(P<0.05),and the heterosis value was 27.88%.Therefore,the backcross breeding was shown an effective way to improve the glycogen,fatty acids,and TAAs of GG,and the glycogen of AA.This study provided useful information to characterize the benefits of backcrossing in nutritional quality,which will facilitate the production of differentiated products and increase the efficiency of the oyster industry.展开更多
Microsatellite DNA technique was used to detect the genetic variation between five hatchery populations of the Pacific oyster from China and two wild populations from Japan. Seven microsatellite loci screened in this ...Microsatellite DNA technique was used to detect the genetic variation between five hatchery populations of the Pacific oyster from China and two wild populations from Japan. Seven microsatellite loci screened in this study showed high polymorphism in both hatchery and wild populations, as observed in an average number of allele per locus （19.1-29.9） and average expected heterozygosity （0.916-0.958）. No significant difference in average allelic richness or expected heterozygosity was observed between Chinese hatchery populations and Japanese wild populations. Pairwise Fsr values and heterogeneity tests of allele frequencies showed significant genetic differentiation between all populations. According to the neighbor-joining tree constructed on the basis of the Dc distance, the seven populations fell into three groups showing a clear division between hatchery and wild populations, and between the northern and southern hatchery populations. Assignment tests correctry assigned high percentages （97%-100%） of individuals to their original populations and demonstrated the feasibility of microsatellite analysis for discrimination between populations. The information obtained in this study is useful for designing suitable management guidelines and selective breeding programs for the Pacific oyster in China.展开更多
基金supported by the Agricultural Seed Improvement Project of Shandong Province(No.2022 LZGCQY010)the Taishan Industrial Experts Programthe Science and Technology Program of Fujian Province(No.2024N3003)。
文摘Triploid Pacific oysters(Crassostrea gigas)are highly valued due to their rapid growth and low fertility,making them commercially desirable.However,these reproductive characteristics also hinder their capability to produce subsequent generations.Large-scale triploid production relies on crossing female diploid and male tetraploid oysters.This study assessed the effects of shell morphology on body weight and fecundity in diploid and tetraploid oysters using multiple regression and path analysis.Substantial correlations were found between shell morphology and body weight traits,as well as between shell morphology and fecundity traits across diploid and tetraploid oysters.Path analysis revealed that shell morphology traits significantly impact body weight and fecundity in both diploids and tetraploids.Among these traits,shell height had the strongest direct effect on body weight and fecundity,while shell height and shell length notably contributed through indirect effects.These findings highlight the importance of shell height in shaping body weight and fecundity in diploid and tetraploid Pacific oysters,indicating that selective breeding,with a particular focus on enhancing shell height,could simultaneously promote increases in shell length.
基金Supported by the Central Public-interest Scientific Institution Basal Research Fund,YSFRI,CAFS(No.20603022024016)the Central Public-interest Scientific Institution Basal Research Fund,CAFS(Nos.2023TD52,2023TD76)the earmarked fund for CARS(No.CARS-49)。
文摘Crassostrea gigas has good taste and high nutritional value;however,there are few assessments of comprehensive and panoramic analyses of the nutritional quality of the northern oyster.To study the nutritional characteristics of C.gigas from different sources(ploidy,region,size,and culture mode),C.gigas from various ploidy(diploid and triploid),regions(Rushan,Off-site fattening,and Rongcheng),sizes(small,medium,and large)and culture modes(nearshore and offshore)were selected for comparative analyses.The nutritional components(moisture,protein,fat,and mineral),flavor substances(taste amino acids,nucleotides,and succinic acid),and functional indices(eicosapentaenoic acid(EPA),docosahexaenoic acid(DHA),and taurine)of C.gigas were determined.Principal component analysis(PCA)was used to comprehensively evaluate the oysters and investigate the variations in nutritional quality.The PCA results indicate that protein,essential fatty acids,selenium,zinc,taste amino acids,taurine,EPA,and DHA were core components contributing to 82.25%of the cumulative variance,providing a more comprehensive reflection of the nutrient composition of C.gigas.The extensive quality rankings for the C.gigas were as follows:diploid>triploid,Rushan>fattening>Rongcheng,medium>large>small,and offshore>nearshore.The score rank revealed that diploid oysters of medium-size from Rushan demonstrated superior nutritional quality compared to other tested samples.This is the first comprehensive and systematic investigation of C.gigas in northern China to reveal the feature of nutrients,flavor,and functional components.The study provided data support for the culture,consumption,processing,research,and nutritional quality improvement of oyster industry.
基金supported by the Natural Science Foundation of Guangdong Province(grant number 2021A1515011485)the Traditional Chinese Medicine Multidisciplinary Innovation Team Program of Liaoning Province(grant number LNZYYCXTD-JCCX-002)+1 种基金the Key Laboratory foundation of Ministry of Education for TCM Viscera State Theory and Applications of Liaoning University of Traditional Chinese Medicine(grant number.zyzx1807)“Three levels”Talent Construction Projects in Zhuhai College of Science and Technology.
文摘Prostatic carcinoma(PCa)has become one of the most common cancers among men worldwide,with both incidence and mortality rates steadily rising.Although current treatments are effective in the early stages of PCa,many cases eventually progress to castration-resistant prostate cancer(CRPC),and led to treatment failure.To develop new therapeutic strategies to ameliorate the survival of PCa patients then has pressed the need on medicinal researchers.Of traditional Chinese medicinal herbs,Angelica gigas Naka(AGN),and its major pyranocoumarins were broadly reported on the effect of anti-PCa.However,existing reviews mainly focus on decursin(D),decursinol angelate(DA),and decursinol(DOH),without fully exploring other coumarins in AGN.Moreover,most reviews discuss general anticancer effects,with limited emphasis on PCa specifically.This review made a comprehensive summary of the coumarin components of AGN,and depicted the anti-PCa effects and mechanisms,giving a solid research support for drug discovery and development.This review also featured pharmacokinetic advantages and therapeutic potential of DOH,in order to suggest possibilities to overcome the in vivo transformation limitations of D and DA,and shed light on CRPC treatment.We also recommend future studies focus on more in vivo evidence,safety and toxicity evaluation,and clinical validation in humans.
基金founded by the National Key R&D Program of China(No.2022YFD2400305)the Earmarked Fund for Agriculture Seed Improvement Project of Shandong Province(Nos.2022LZGCQY010,2021LZGC027 and 2021ZLGX03)the China Agriculture Research System Project(No.CARS-49)。
文摘A crossbreeding program was established in 2019 to address the declining Crassostrea gigas harvests caused by Pacific Oyster Mortality Syndrome(POMS).As a part of the program,this study was performed to estimate the genetic structure underlying phenotypic variation.Fifteen complete diallel crossings of C.gigas and C.angulata,comprising 60 full-sib families,were used to evaluate the general combining ability(GCA)and specific combining ability(SCA),as well as genotype and environment interactions for shell height(SH),summer survival(SS),and thermal tolerance(TT)of reciprocal hybrids GA(C.gigas♀×C.angulata♂)and AG(C.angulata♀×C.gigas♂)grown in Rongcheng and Rushan,Shandong Province,China.The results suggested that heterosis of the reciprocal hybrids was evident for SH,SS,and TT.The hybrid GA had larger heterosis than AG in both testing environments,and can be a potential donor in the breeding program.The male C.gigas had better GCA for SH in Rongcheng,whereas male C.angulata was a good general combiner for SS and TT in both Rongcheng and Rushan.The estimate of SCA was much higher than GCA for SH and lower than GCA for TT.To harness both additive and non-additive genetic effects,combination breed-ing could be taken to develop hybrid varieties possessing both thermal tolerance and fast-growing traits.The positive correlations between SH and TT suggested that these traits could be improved simultaneously.The significant G×E interactions demonstrated the importance to undertake site-specific breeding programs in different environments.Overall,this study can provide essential information for developing crossbreeding strategies for the oyster farming industry.
基金supported by grants from the National Natural Science Foundation of China(No.32373115)the Earmarked Fund for Agriculture Seed Improvement Project of Shandong Province(Nos.2022LZGCQY010,2021ZLGX03 and 2021TSGC1240)the China Agriculture Research System Project(No.CARS-49)。
文摘Crassostrea gigas is distinguished by its robust fertility,adaptability to various environmental conditions,and rich nutritional profile,which render it a cornerstone of the global shellfish market.Tetraploid oysters,in particular,is a pivotal role within the oyster industry,however,their growth and survival characteristics need to be improved.This study aimed to assess the viability of enhancing the growth and survival characteristics of tetraploid C.gigas through genetic selection.This was achieved by investigating the heritability and genetic correlation of growth and survival at various stages of C.gigas development.Genetic parameters were assessed based on in-group correlations in 28 full-sib families during the larval stage(days 3,8,13,18,and 23 after fertilization).The heritability of larval shell height and shell length ranged from 0.50 to 0.71 and 0.44 to 0.71,respectively,and varied with age.The heritability of larval survival was 0.40–0.64,indicating that it is viable to enhancelarval survival through selection.The genetic correlation between the growth traits of larvae at different ages was highly positive(0.959–0.999),indicating that the selection of a single growth trait could cause the positive response of other growth traits.However,the genetic correlation between larval survival and growth traits was low,showing a significant negative correlation(-0.198–-0.293)at day 23 of age,suggesting thatselecting for enhanced survival in tetraploid C.gigas may result in a detrimental impact on growth traits.The results are helpful for future researches to evaluate the genetic parameters related to growth and survival traits in juvenile and adult stages of the tetraploid family of C.gigas,which can provide further guidance for the selection of tetraploid C.gigas.
基金supported by grants from the National Key R&D Program of China(No.2022YFD2400305)the Key R&D Program of Shandong Province(Nos.2022LZ GCQY010,2021ZLGX03 and 2021TSGC1240)the China Agriculture Research System Project(No.CARS-49).
文摘Tetraploid oysters frequently exhibit growth and survival rates inferior to diploid and triploid oysters.Tetraploid Pacific oysters(Crassostrea gigas)are pivotal as broodstock in the triploid C.gigas industry.However,the high mortality of tetraploid C.gigas has occurred in production practice with the increasing temperature.The transcriptional patterns of high temperature-susceptible and-tolerant tetraploid C.gigas were compared in response to prolonged thermal treatment.The H was defined as oysters that have not been thermally treated.The susceptible and tolerant oysters after thermal treatment were designed as TS and TH,respectively.The survival rate of tetraploid C.gigas was low(6.33%±2.87%)after thermal treatment.A total of 5147,5250,and 433 differentially expressed genes(DEGs)were detected in TS vs.TH,TS vs.H,and TH vs.H groups,respectively.Functional enrichment analysis indicated that DEGs were notably enriched in various pathways,including the NF-kappa B signaling pathway,apoptosis,TNF signaling pathway,and arginine and proline metabolism,across both TS vs.TH and TS vs.H groups.Among the DEGs under thermal treatment in susceptible oysters,the translation regulation genes like eIF2a kinase 1,eIF2a kinase 3,MKNK1,and ATF-4 exhibited differential expressions.Susceptible oysters displayed a higher number of differentially expressed IAP genes compared to tolerant oysters,while the expression pattern of HSP genes differed between susceptible and tolerant oysters.This study underscores the contrasting response of susceptible and tolerant tetraploid C.gigas to thermal treatment,suggesting that high temperature-susceptible tetraploid C.gigas may be more responsive to rapid alterations in immune response and apoptosis compared to high temperature-tolerant tetraploid C.gigas.It is necessary to improve the high temperature tolerance of tetraploid C.gigas by selective breeding to promote the development of the triploid industry.
基金grants from the National Key R&D Program of China(No.2022YFD2400305)the Excellent Seed Project of Shandong Province(No.2022LZGCQY010)+1 种基金the Science and Technology Program of Fujian Province(No.2024N3003)the Research on Breeding Technology of Candidate Species for Guangdong Modern Marine Ranching(No.2024-MRB00-001)。
文摘Recently,allotriploids from Pacific oysters(Crassostrea gigas)and Fujian oysters(C.angulata)have been grown for aquaculture.However,the viability of these allotriploids remains uncertain.In this study,two autotriploids,TGG(diploid C.gigas♀×tetraploid C.gigas♂)and TAA(diploid C.angulata♀×tetraploid C.angulata♂),and two allotriploids,TGA(diploid C.gigas♀×tetraploid C.angulata♂)and TAG(diploid C.angulata♀×tetraploid C.gigas♂),were studied to assess the heterosis in growth and survival at different temperatures and salinities.The results showed that during the larval stage,TAG exhibited increased heterosis in growth and survival when temperature rose.During the adult stage,the growth of TGA significantly outperformed other triploids at higher temperatures(23 and 28℃)and salinities(25 and 30).In contrast,TAG demonstrated the highest survival probability across all conditions except at salinity 25,where it equaled TAA after day 19.The highest oxygen consumption rates(OCR)of TGA and TAG were observed at 23 and 28℃,while the ammonia excretion rate(AER)of TAG was significantly higher than that of TGA at 23℃.These physiological parameters reflect the advantage of TAG in terms of survival.Notably,the temperature coefficient of allotriploids was higher than that of autotriploids in the range of 18–23℃.At 28℃,TAG showed the highest superoxide dismutase(SOD)and catalase(CAT)activities and the lowest malondialdehyde(MDA)content,showing its advantage when encountering high-temperature.
基金supported by grants from the Key R&D Program of Shandong Province(No.2022LZGCQY010)the National Natural Science Foundation of China(No.32373115)the China Agriculture Research System Project(No.CARS-49).
文摘Triploid oysters are widely cultured due to their superior growth compared to diploids.However,differences in tempera-ture-salinity adaptation between di-and triploid oysters remain inconclusive.This study compared the survival rates,antioxidant en-zyme activities,and gene expressions in di-and triploid Pacific oyster Crassostrea gigas cultured in different temperatures(17,20,23,26,and 29℃)and salinities(18,22,26,30,and 34).Results showed that the optimum survival condition for both di-and triploids is 23℃/30.At 23℃,triploids exhibited significantly higher superoxide dismutase activity and lower heat shock protein 70(Hsp70)expression than diploids.At 29℃,triploids exhibited significantly higher survival rates than diploids.Across varying tem-peratures,triploids demonstrated significantly higher survival rates and antioxidant enzyme activities,along with lower malondialdehyde(MDA)levels and Hsp70 expression compared to diploids.The overall results demonstrate that triploids have a more robust antioxidant ca-pacity,reduced oxidative damage,and lower mortality than diploids under temperature treatments.Additionally,at a salinity of 18,triploids showed significantly higher catalase(CAT)level than diploids.Across varying salinities,triploids maintained lower MDA levels.These results suggest that triploids possess a stronger antioxidant defense under salinity treatments.In conclusion,triploid C.gigas demonstrates superior adaptation to diverse temperature and salinity conditions over diploids and are recommended for culture to improve oyster production.
基金financially supported by the State key research and development plan(2019YFC1605000)the National Natural Science Foundation of China(31871735)。
文摘As an important shellfish group,the oyster can induce severe allergic reactions.We aimed to identify and characterize the major allergen in Crassostrea gigas,and elucidate the molecular basis of its allergenicity and cross-reactivity.The native and recombinant C.gigas-arginine kinase(AK)displayed significant immunoglobulin(Ig)G-and Ig E-binding activity.The Ig E-binding activity of C.gigas-AK could be reduced by thermal treatment and strong acidic and alkaline conditions.Besides,cross-reactivity of AK was demonstrated between shellfish species.Among seven epitope peptides identified here,P2 is responsible for the specificity of C.gigas-AK,while P3 is responsible for cross-reactions between mollusks and crustaceans.Furthermore,Glu98 and His31 in the light chain,Arg101,and Lys57 in the heavy chain are identified as key Ig E residues in recognizing epitopes.These findings provide new insights into the prevention and treatment of shellfish allergy and the development of hypoallergenic shellfish products.
基金supported by the National Natural Science Foundation of China (No. 32341060)the National Key Research and Development Program of China (No.2022YFD2400300)+2 种基金the Key Research and Development Program of Shandong Province (No. 2021ZLGX03)the earmarked fund for China Agriculture Research System (CARS-49)support from the High-Performance Biological Supercomputing Center of the Ocean University of China.
文摘The Pacific oyster(Crassostrea gigas)is a primary shellfish species for aquaculture around the world.However,the industry of Pacific oyster has been impaired by the mass summer mortality caused by environmental perturbations,including hypoxia.Selective breeding of oysters with high hypoxia tolerance is a sustainable approach to prevent economic loss caused by hypoxia.In this study,we constructed 36 C.gigas families and executed the hypoxia stress experiment to estimate genetic parameters for hypoxia tolerance.The survival rate among 36 C.gigas families ranged from 0 to 53.33%,suggesting that high levels of phenotypic variation existed in the trait of hypoxia tolerance.Genetic parameters of hypoxia tolerance estimated by six statistical models showed a low to moderate heritability,ranging from 0.167 to 0.291.The Pearson and Spearman correlation coefficients among families estimated breeding values(EBVs)were high and positive,indicating that different models resulted in similar results in the estimation of breeding values.The phenotypic correlation between growth traits and hypoxia tolerance ranged from-0.030 to 0.061,while genetic correlation ranged from 0.110 to 0.285,implying that growth and hypoxia tolerance were independent traits.This work reported the first estimation of genetic parameters for hypoxia tolerance in C.gigas,and provided valuable information for the genetic improvement of hypoxia tolerance.
基金Supported by the Key Research and Development Program of Shandong(No.2022LZGC015)the National Key R&D Program of China(No.2022YFD2400304)+2 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA24030105)the Key Technology Research and Industrialization Demonstration Projects of Qingdao(No.22-3-3-hygg-2-hy)the China Agriculture Research System of MOF and MARA(No.CARS-49)。
文摘Oysters are of the most economically important bivalves worldwide.It has high nutritional value and is regarded as a good source of proteins,lipids,glycogen,and amino acids.C.gigas and C.angulata are allopatric congeneric dominant oysters that are widely cultivated in the northern and southern coast of China,and have shown remarkable differentiation in the nutritional content.Interspecific hybridization and backcross of the two species are effective ways to improve the nutritional quality of the oyster.Sixteen progenies were constructed based on a 4×4 diallel crosses among broodstock of C.gigas(G),C.angulata(A)and their hybrids GA(H)and AG(R).The glycogen,fatty acids,and amino acids performance of these progenies were evaluated in 22 months after fertilization.The glycogen content of AA was significantly lower than that of the other 15 progenies(P<0.05),while only the GH progeny was significantly higher than the GG(P<0.05),with a heterosis value of 21.06%.The backcross progenies GR exhibited significantly higher saturated fatty acids,eicosapentaenoic acid(EPA),and polyunsaturated fatty acids(PUFAs)content than those of GG(P<0.05),and did not show significant differences from AA.The AA showed significantly higher content of total amino acids(TAAs)than GG(P<0.05).The AH progeny displayed significantly higher taurine(Tau)content than GG(P<0.05),and the heterosis value was 27.88%.Therefore,the backcross breeding was shown an effective way to improve the glycogen,fatty acids,and TAAs of GG,and the glycogen of AA.This study provided useful information to characterize the benefits of backcrossing in nutritional quality,which will facilitate the production of differentiated products and increase the efficiency of the oyster industry.
基金the Ministry of Education (No. NCET-04-0640)the National Natural Science Foundation of China (No. 30571442).
文摘Microsatellite DNA technique was used to detect the genetic variation between five hatchery populations of the Pacific oyster from China and two wild populations from Japan. Seven microsatellite loci screened in this study showed high polymorphism in both hatchery and wild populations, as observed in an average number of allele per locus （19.1-29.9） and average expected heterozygosity （0.916-0.958）. No significant difference in average allelic richness or expected heterozygosity was observed between Chinese hatchery populations and Japanese wild populations. Pairwise Fsr values and heterogeneity tests of allele frequencies showed significant genetic differentiation between all populations. According to the neighbor-joining tree constructed on the basis of the Dc distance, the seven populations fell into three groups showing a clear division between hatchery and wild populations, and between the northern and southern hatchery populations. Assignment tests correctry assigned high percentages （97%-100%） of individuals to their original populations and demonstrated the feasibility of microsatellite analysis for discrimination between populations. The information obtained in this study is useful for designing suitable management guidelines and selective breeding programs for the Pacific oyster in China.
