Kumamoto oysters(Crassostrea sikamea)are important marine aquaculture shellfish because of their taste and round shell shape.Due to its small size,selective breeding is required to improve its market size,but there ar...Kumamoto oysters(Crassostrea sikamea)are important marine aquaculture shellfish because of their taste and round shell shape.Due to its small size,selective breeding is required to improve its market size,but there are no reports on traits suitable for direction selection and reproductive productivity of Kumamoto oysters of different ages.In this study,path analysis and one-way ANOVA were used to explore the influential indices of oyster body weight and fecundity.The results showed that shell height was the main factor affecting the body weight of Kumamoto oysters at one-year-old and two-year-old,followed by shell length.Body weight was the main factor influencing fecundity,and shell height showed a significant correlation with fecundity.Therefore,shell height should be considered the first parameter for selection when selecting Kumamoto oysters for body weight as the direct selection target.When one-year-old and two-year-old Kumamoto oysters were selected as parents from Xiangshan Bay,hatching parameters and growth parameters of F1 generation larvae were measured.The fecundity and egg diameters were 1.72×10^(6)and 46.60±3.62μm,respectively,which were significantly greater than one-aged oysters(5.86×10^(5),40.26±3.52μm).The hatching parameters(fertilized egg size,fertilization rate,and hatching rate)and larval growth performance(D-stage veliger and veliger)were similar and did not differ significantly(P>0.05),and after metamorphosis,there was also no significant difference in shell height size at 40 days of age(P>0.05).Therefore,there was no significant effect of age on reproduction,larval development,and the early growth of Kumamoto oysters.These results could provide a basis for parental sources and proper traits for Kumamoto oyster selection,which is beneficial to developing and utilizing this excellent germplasm resource.展开更多
There exist severe metal pollutions along the Jiulongjiang estuary in South China. In order to unravel the biological eff ects caused by metal pollutions, proteomic responses were investigated by two-dimensional elect...There exist severe metal pollutions along the Jiulongjiang estuary in South China. In order to unravel the biological eff ects caused by metal pollutions, proteomic responses were investigated by two-dimensional electrophoresis-based proteomics in oysters Crassostrea sikamea from metal pollution sites, Jinshan (JS) and Baijiao (BJ), and a relatively clean site, Jiuzhen (JZ), along the Jiulongjiang estuary. Results indicated that metal pollutions mainly induced cellular injuries, oxidative and immune stresses, and disturbed ion homeostasis in oysters C . sikamea from both JS and BJ sites via diff erential pathways. Furthermore, metal pollution enhanced transcriptional initiation in oysters from JS site. In addition, the Cu and Fe pollution might be indicated by the 78 kDa glucose regulated protein and ferritin GF1 in oysters C . sikamea , respectively. The study confirms that proteomics is a promising approach to characterize the underlying mechanisms of responses to metal pollution in oysters.展开更多
Quantitative real-time polymerase chain reaction(q RT-PCR) is a rapid and reliable technique which has been widely used to quantifying gene transcripts(expression analysis). It is also employed for studying heterosis,...Quantitative real-time polymerase chain reaction(q RT-PCR) is a rapid and reliable technique which has been widely used to quantifying gene transcripts(expression analysis). It is also employed for studying heterosis, hybridization breeding and hybrid tolerability of oysters, an ecologically and economically important taxonomic group. For these studies, selection of a suitable set of housekeeping genes as references is crucial for correct interpretation of q RT-PCR data. To identify suitable reference genes for oysters during low temperature and low salinity stresses, we analyzed twelve genes from the gill tissue of Crassostrea sikamea(SS), Crassostrea angulata(AA) and their hybrid(SA), which included three ribosomal genes, 28 S ribosomal protein S5(RPS5), ribosomal protein L35(RPL35), and 60 S ribosomal protein L29(RPL29); three structural genes, tubulin gamma(TUBγ), annexin A6 and A7(AA6 and AA7); three metabolic pathway genes, ornithine decarboxylase(OD), glyceraldehyde-3-phosphate dehydrogenase(GAPDH) and glutathione S-transferase P1(GSP); two transcription factors, elongation factor 1 alpha and beta(EF1α and EF1β); and one protein synthesis gene(ubiquitin(UBQ). Primers specific for these genes were successfully developed for the three groups of oysters. Three different algorithms, ge Norm, Norm Finder and Best Keeper, were used to evaluate the expression stability of these candidate genes. Best Keeper program was found to be the most reliable. Based on our analysis, we found that the expression of RPL35 and EF1α was stable under low salinity stress, and the expression of OD, GAPDH and EF1α was stable under low temperature stress in hybrid(SA) oyster; the expression of RPS5 and GAPDH was stable under low salinity stress, and the expression of RPS5, UBQ, GAPDH was stable under low temperature stress in SS oyster; the expression of RPS5, GAPDH, EF1β and AA7 was stable under low salinity stress, and the expression of RPL35, EF1α, GAPDH and EF1β was stable under low temperature stress in AA oyster. Furthe展开更多
The production of an all-triploid population by mating tetrapioid males with diploid females is the best and most fundamental method for the large-scale production of triploid oysters.Obtaining a stable tetrapioid pop...The production of an all-triploid population by mating tetrapioid males with diploid females is the best and most fundamental method for the large-scale production of triploid oysters.Obtaining a stable tetrapioid population is essential for guaranteed production in industrialized triploid cultivation.C.hongkongensis and C.sikamea are important oyster breeding species in southern China,and have great economic value.However,there are not any published data on inducing tetrapioid C.hongkongensis or C.sikamea.Therefore,we investigated tetrapioid induction in these two oyster species by inhibiting the PB1 release in diploid fertilized eggs using Cytochalasin B(CB)under 31℃,15%o salinity.The results confirmed that the optimal tetrapioid induction conditions for C.hongkongensis were a CB concentration of 0.50 mg/L with induction starting at 9.0 min after fertilization,and stopping at 21.0 min after fertilization;the induction efficiency index reached 0.123 under these conditions.The optimal tetrapioid induction conditions for C.sikamea were a CB concentration of 0.50 mg/L,with induction starting at 7.5 min after fertilization and stopping at 18 min after fertilization;the induction efficiency index could be as high as 0.281 under these conditions.However,we confirmed that the tetrapioid rate decreased with larval growth,and no tetrapioids were detected in the juvenile period of either C.hongkongensis or C.sikamea.This may be attributed to the very low survival of the tetrapioid larvae induced by this method,especially as most tetrapioid larvae died during the first three days.In summary,it is simple to directly induce tetrapioid C.hongkongensis and C.sikamea larvae by inhibiting the PB1 release of diploid zygotes,but the low survival rate makes it challenging to obtain viable juvenile tetrapioids.展开更多
Crassostrea sikamea(C.sikamea)is an important edible and medicinal seafood in China.In the present study,a compound named flazin was separated and identified from the ethyl acetate extract of C.sikamea(EAECs)for the f...Crassostrea sikamea(C.sikamea)is an important edible and medicinal seafood in China.In the present study,a compound named flazin was separated and identified from the ethyl acetate extract of C.sikamea(EAECs)for the first time.In addition,the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetra zolium(MTS)assay revealed that EAECs and flazin inhibited the transformation of splenic lymphocytes in vitro.Moreover,flazin(20μg·mL^(−1))altered the populations of splenic lymphocyte subtypes.Real-time quantitative PCR(RT-qPCR)analysis and enzyme-linked immunosorbent assay(ELISA)showed that flazin suppressed the mRNA expression and secretion of TNF-αand IL-2,and reversed Concanavalin A(ConA)-induced mRNA up-regulation and protein secretion of TNF-αand IL-2.Western blot results showed that flazin reversed ConA-induced increases in p-ERK1/2 and p-p38 in splenocytes.In conclusion,flazin exhibits effective immunomodulatory function and may be useful for treating immune-related disorders,which indicates the application potential of C.sikamea as a functional food or immunomodulator.展开更多
基金supported by grants from the“3315”Innovative Team of Ningbo City,the Science and Technology Planning Project of Ningbo City(2021S009).
文摘Kumamoto oysters(Crassostrea sikamea)are important marine aquaculture shellfish because of their taste and round shell shape.Due to its small size,selective breeding is required to improve its market size,but there are no reports on traits suitable for direction selection and reproductive productivity of Kumamoto oysters of different ages.In this study,path analysis and one-way ANOVA were used to explore the influential indices of oyster body weight and fecundity.The results showed that shell height was the main factor affecting the body weight of Kumamoto oysters at one-year-old and two-year-old,followed by shell length.Body weight was the main factor influencing fecundity,and shell height showed a significant correlation with fecundity.Therefore,shell height should be considered the first parameter for selection when selecting Kumamoto oysters for body weight as the direct selection target.When one-year-old and two-year-old Kumamoto oysters were selected as parents from Xiangshan Bay,hatching parameters and growth parameters of F1 generation larvae were measured.The fecundity and egg diameters were 1.72×10^(6)and 46.60±3.62μm,respectively,which were significantly greater than one-aged oysters(5.86×10^(5),40.26±3.52μm).The hatching parameters(fertilized egg size,fertilization rate,and hatching rate)and larval growth performance(D-stage veliger and veliger)were similar and did not differ significantly(P>0.05),and after metamorphosis,there was also no significant difference in shell height size at 40 days of age(P>0.05).Therefore,there was no significant effect of age on reproduction,larval development,and the early growth of Kumamoto oysters.These results could provide a basis for parental sources and proper traits for Kumamoto oyster selection,which is beneficial to developing and utilizing this excellent germplasm resource.
基金Supported by the National Natural Science Foundation of China(Nos.41676114,21237004,41506138)the Qingdao National Laboratory for Marine Science and Technology(No.QNLM201701)the “Youth Innovation Promotion Association CAS”(No.2015169)
文摘There exist severe metal pollutions along the Jiulongjiang estuary in South China. In order to unravel the biological eff ects caused by metal pollutions, proteomic responses were investigated by two-dimensional electrophoresis-based proteomics in oysters Crassostrea sikamea from metal pollution sites, Jinshan (JS) and Baijiao (BJ), and a relatively clean site, Jiuzhen (JZ), along the Jiulongjiang estuary. Results indicated that metal pollutions mainly induced cellular injuries, oxidative and immune stresses, and disturbed ion homeostasis in oysters C . sikamea from both JS and BJ sites via diff erential pathways. Furthermore, metal pollution enhanced transcriptional initiation in oysters from JS site. In addition, the Cu and Fe pollution might be indicated by the 78 kDa glucose regulated protein and ferritin GF1 in oysters C . sikamea , respectively. The study confirms that proteomics is a promising approach to characterize the underlying mechanisms of responses to metal pollution in oysters.
基金supported by the National Natural Science Foundation of China (No.31172403)
文摘Quantitative real-time polymerase chain reaction(q RT-PCR) is a rapid and reliable technique which has been widely used to quantifying gene transcripts(expression analysis). It is also employed for studying heterosis, hybridization breeding and hybrid tolerability of oysters, an ecologically and economically important taxonomic group. For these studies, selection of a suitable set of housekeeping genes as references is crucial for correct interpretation of q RT-PCR data. To identify suitable reference genes for oysters during low temperature and low salinity stresses, we analyzed twelve genes from the gill tissue of Crassostrea sikamea(SS), Crassostrea angulata(AA) and their hybrid(SA), which included three ribosomal genes, 28 S ribosomal protein S5(RPS5), ribosomal protein L35(RPL35), and 60 S ribosomal protein L29(RPL29); three structural genes, tubulin gamma(TUBγ), annexin A6 and A7(AA6 and AA7); three metabolic pathway genes, ornithine decarboxylase(OD), glyceraldehyde-3-phosphate dehydrogenase(GAPDH) and glutathione S-transferase P1(GSP); two transcription factors, elongation factor 1 alpha and beta(EF1α and EF1β); and one protein synthesis gene(ubiquitin(UBQ). Primers specific for these genes were successfully developed for the three groups of oysters. Three different algorithms, ge Norm, Norm Finder and Best Keeper, were used to evaluate the expression stability of these candidate genes. Best Keeper program was found to be the most reliable. Based on our analysis, we found that the expression of RPL35 and EF1α was stable under low salinity stress, and the expression of OD, GAPDH and EF1α was stable under low temperature stress in hybrid(SA) oyster; the expression of RPS5 and GAPDH was stable under low salinity stress, and the expression of RPS5, UBQ, GAPDH was stable under low temperature stress in SS oyster; the expression of RPS5, GAPDH, EF1β and AA7 was stable under low salinity stress, and the expression of RPL35, EF1α, GAPDH and EF1β was stable under low temperature stress in AA oyster. Furthe
基金This research was supported by the National Science Foundation of China(32002387)the Chinese Ministry of Science and Technology through the National Key Research and Devel-opment Program of China(2018YFC1406505,2018YFD0901400,2020YFD0901102)+2 种基金Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(GML2019ZD0404)the Innovation Academy of South China Sea Ecology and Environmental Engineering,Chinese Academy of Sciences(ISEE2018PY01,ISEE2018ZD02,ISEE2018PY03)the China Agriculture Research System Project(CARS-49),and the Science and Technology Planning Project of Guangdong Province,China(2017B030314052).
文摘The production of an all-triploid population by mating tetrapioid males with diploid females is the best and most fundamental method for the large-scale production of triploid oysters.Obtaining a stable tetrapioid population is essential for guaranteed production in industrialized triploid cultivation.C.hongkongensis and C.sikamea are important oyster breeding species in southern China,and have great economic value.However,there are not any published data on inducing tetrapioid C.hongkongensis or C.sikamea.Therefore,we investigated tetrapioid induction in these two oyster species by inhibiting the PB1 release in diploid fertilized eggs using Cytochalasin B(CB)under 31℃,15%o salinity.The results confirmed that the optimal tetrapioid induction conditions for C.hongkongensis were a CB concentration of 0.50 mg/L with induction starting at 9.0 min after fertilization,and stopping at 21.0 min after fertilization;the induction efficiency index reached 0.123 under these conditions.The optimal tetrapioid induction conditions for C.sikamea were a CB concentration of 0.50 mg/L,with induction starting at 7.5 min after fertilization and stopping at 18 min after fertilization;the induction efficiency index could be as high as 0.281 under these conditions.However,we confirmed that the tetrapioid rate decreased with larval growth,and no tetrapioids were detected in the juvenile period of either C.hongkongensis or C.sikamea.This may be attributed to the very low survival of the tetrapioid larvae induced by this method,especially as most tetrapioid larvae died during the first three days.In summary,it is simple to directly induce tetrapioid C.hongkongensis and C.sikamea larvae by inhibiting the PB1 release of diploid zygotes,but the low survival rate makes it challenging to obtain viable juvenile tetrapioids.
基金Education Department of Jilin Province(No.JJKH20201177KJ)the Foundation of Department of Human Resources and Social Security of Jilin Province(No.2020009)the Foundation of Jilin Province Development and Reform Commission(No.2020C015).
文摘Crassostrea sikamea(C.sikamea)is an important edible and medicinal seafood in China.In the present study,a compound named flazin was separated and identified from the ethyl acetate extract of C.sikamea(EAECs)for the first time.In addition,the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetra zolium(MTS)assay revealed that EAECs and flazin inhibited the transformation of splenic lymphocytes in vitro.Moreover,flazin(20μg·mL^(−1))altered the populations of splenic lymphocyte subtypes.Real-time quantitative PCR(RT-qPCR)analysis and enzyme-linked immunosorbent assay(ELISA)showed that flazin suppressed the mRNA expression and secretion of TNF-αand IL-2,and reversed Concanavalin A(ConA)-induced mRNA up-regulation and protein secretion of TNF-αand IL-2.Western blot results showed that flazin reversed ConA-induced increases in p-ERK1/2 and p-p38 in splenocytes.In conclusion,flazin exhibits effective immunomodulatory function and may be useful for treating immune-related disorders,which indicates the application potential of C.sikamea as a functional food or immunomodulator.