The yellow-colored line of pearl oyster Pinctada fucata martensii displays a yellow prismatic layer and a white nacreous layer that can be used as an ideal model for research on shell color formation.Micro-Raman spect...The yellow-colored line of pearl oyster Pinctada fucata martensii displays a yellow prismatic layer and a white nacreous layer that can be used as an ideal model for research on shell color formation.Micro-Raman spectroscopy and transcriptome analyses were performed to explore the potential molecular mechanism underlying the phenotype differentiation.The micro-Raman spectroscopy results indicate that the prismatic layer exhibits distinct characteristic peaks of carotenoids,while these peaks are not prominent in the nacreous layer.In the transcriptome comparison of the central zone of mantle and mantle edge tissue,which function in nacreous and prismatic layer formation,respectively,935 significantly differentially expressed genes(DEGs)were identified,with 385 genes upregulated and 227 genes downregulated(|log_(2)(Fold change)|>1 and false discovery rate<0.05)in the mantle edge tissue.Among these genes,some were associated with melanoma/melanogenesis,such as tyrosinase,zinc metalloprotease,glutathione S-transferase,and ATP-binding cassette sub-family;some were associated with the carotenoid-related pathway,including scavenger receptors,cytochrome P450 and lipoprotein receptor.Genes associated with porphyrin metabolism,including porphobilinogen deaminase,and copper/zinc superoxide dismutase,and genes associated with shell matrix protein,including amorphous calcium carbonate binding protein,shematrin,PIF,and collagen,also exhibited significantly different expressions.It is speculated that the different colours between prismatic layer and nacreous layer in the yellow-colored line of P.f.martensii might be resulted from melanin,carotenoids and porphyrin metabolism,while genes related to shell structure and biomineralization might also affect coloration.Our results provide new insights to understand the mechanism of shell color formation in mollusca.展开更多
Aneuploidy embryos of Pinctada martensii Dunker are produced during tetraploid induction by inhibiting the first polar body in eggs from triploid fertilized with haploid sperms with cytochalasin B treatment. Chromosom...Aneuploidy embryos of Pinctada martensii Dunker are produced during tetraploid induction by inhibiting the first polar body in eggs from triploid fertilized with haploid sperms with cytochalasin B treatment. Chromosome analysis reveals that there are 88.18 ±6.79% aneuploidy embryos, and 28.70% aneuploids in pearl oysters of one-year age These aneuploids have five chromosomal conditions, such as 2n + 1(29), 2n + 2 (30), 3n-2 (40), 3n-1(41) and 3n + 1 (43). Results of growth measurement show that there is no significant difference between aneuploids (as a group) and diploids in body size and weight (p ＞ 0.10), but the aneuploide is obviously different from triploid (p ＜ 0.01). The mean body size and weight of aneuploids in diploid condition (2n ± 1 and 2n ± 2) are significantly smaller than those of diploids (p ＜ 0.01),but aneuploids within triploid condition (3n ± 1 and 3n ± 2) are not smaller than diploids in body size and weight (p ＞ 0.1).This study indicates Pinctada martensii Dunker could tolerate aneuploidy by 7 ～ 14% of the haploid genome, and that aneuploids of this species are viable under certain conditions.展开更多
120 pearl oysters （Pinctada martensii） were randomly sampled from F1 population, and shell length, shell width, shell height, shell weight and total weight of each sample were measured. Correlation and path analysis...120 pearl oysters （Pinctada martensii） were randomly sampled from F1 population, and shell length, shell width, shell height, shell weight and total weight of each sample were measured. Correlation and path analysis were conducted on the basis of measurement data. The results showed that shell length, shell width, shell height, shell weight and total weight were significantly correlated （P 〈 0.05）. Total weight was significantly and positively correlated with shell weight （r = 0.8970）, shell height （r = 0.6974）, shell width （r = 0.6521） and shell length （r = 0.5486）. Shell weight, shell height, shell width and shell length had positive and direct effects on total wet weight, with the values of 0.6356, 0.1872, 0.1814 and 0.0599, respectively. The results indicated that growth traits （shell length, shell width, shell height, shell weight and total wet weigh） of the F1 population could be improved by direct or indirect selection.展开更多
In May of 2007,the second generation selected （SS） and control （SC） groups of pearl oyster Pinctada martensii were established by selecting 10% breeders with the largest and mean shell length,respectively,from the...In May of 2007,the second generation selected （SS） and control （SC） groups of pearl oyster Pinctada martensii were established by selecting 10% breeders with the largest and mean shell length,respectively,from the first generation selected group.Growth performance of the SS and SC groups were compared on the basis of measurement data at Days 8,18,60,95,195 and 365.On Day 365,100 individuals （60.0–75.0 mm at shell length） were sampled from each group and then subjected to the experiment where physiological parameters such as filtrate rate,oxygen consumption and ammonia excretion were measured at 15,20,25 and 30°C.The results show that the SS group had significantly larger mean shell length and shell height than the SC group at Days 8,18,60,95,195 and 365 （P 0.05）.The genetic gains at different ages varied from 6.0% to 17.0% for shell length and 5.7% to 14.6% for shell height,respectively.At 15,20,25 and 30 ° C,the SS groups had significantly larger filtrate rate than the SC group （P 0.05）.At 15 and 25 °C,the differences in oxygen consumption rate between the SS and SC groups were not significant （P 0.05）.At 20 and 30 °C,however,the oxygen consumption rate of the SS group was significantly larger than the SC group （P 0.05）.At 15,20,25 and 30 °C,there were no significant differences in ammonia excretion rate between the SS and SC groups （P 0.05）.The present results indicate that there existed considerable genetic variability in the base population and a further selection could be likely fruitful.Mass selection for faster growth might produce animals that had higher intake of metabolizable energy by virtue of faster filtrating behavior.展开更多
The present study investigated the removal of inorganic arsenic from Pinctada martensii enzymatic hydrolysate through unmodified resin （D296） and Zr（IV）-loaded chelating resin （Zr-D401）. By loading Zr to macropo...The present study investigated the removal of inorganic arsenic from Pinctada martensii enzymatic hydrolysate through unmodified resin （D296） and Zr（IV）-loaded chelating resin （Zr-D401）. By loading Zr to macroporous chelating resin D401, the as exchange adsorption active sites are generated. This transforms D401 from a material that does not have the arsenic adsorption capacity into a material that has excellent arsenic exchange adsorption capacity. The static adsorption experiments were conducted to investigate the optimal removal condition for D296 and Zr-D401. The experimental results show that： the optimum condition for D296 is that T= 25℃, pH= 5, resin additive amount= 1 g （50 mL）-1, and contact time = 10 h, the corresponding arsenic removal rate being 65.7%, and protein loss being 2.33%; the optimum condition for Zr-D401 is that T=25 ℃, pH = 8, resin additive amount= 1 g （50 mL）-1, and contact time=10 h, the corresponding arsenic removal rate being 70.3%, and protein loss being 4.65%. These results show that both of the two resins are effective in arsenic removal for preserving useful substance. Our research provides scientific evidence and advances in the processing technology for heavy metal removal in shellfish.展开更多
A new enzyme (alkaline protease 894) obtained from the marine extremophile Flavobacterium yellowsea (YS-80-122) has exhibited strong substrate-binding and catalytic activity, even at low temperature, but the character...A new enzyme (alkaline protease 894) obtained from the marine extremophile Flavobacterium yellowsea (YS-80-122) has exhibited strong substrate-binding and catalytic activity, even at low temperature, but the characteristics of the hydrolysis with this enzyme are still unclear. The pearl oyster Pinctada martensii was used in this study as the raw material to illustrate the kinetic properties of protease 894. After investigating the intrinsic relationship between the degree of hydrolysis and several factors, including initial reaction pH, temperature, substrate concentration, enzyme concentration, and hydrolysis time, the kinetics model was established. This study showed that the optimal conditions for the enzymatic hydrolysis were an initial reaction pH of 5.0, temperature of 30°C, substrate concentration of 10% (w/v), enzyme concentration of 2 500 U/g, and hydrolysis time of 160 min. The kinetic characteristics of the protease for the hydrolysis of P. martensii were obtained. The inactivation constant was found to be 15.16/min, and the average relative error between the derived kinetics model and the actual measurement was only 3.04%, which indicated a high degree of fitness. Therefore, this study provides a basis for the investigation of the concrete kinetic characteristics of the new protease, which has potential applications in the food industry.展开更多
Pinctada martensii is an important shellfish for the production of sea pearls in China.To improve the growth performance of P.martensii,we successfully established three complete diallel crosses using three new variet...Pinctada martensii is an important shellfish for the production of sea pearls in China.To improve the growth performance of P.martensii,we successfully established three complete diallel crosses using three new varieties of P.martensii,which were named Haiyou No.1,Haixuan No.1,and Nanke No.1,to investigate the growth performance of each self-cross line and hybrid line in Beihai,Guangxi Zhuang Autonomous Region,China.Generally,high fertilization and hatching rates were observed in the experiment,suggesting that there was no sperm-egg recognition barrier among these three P.martensii varieties.The survival rate of the self-cross lines was relatively higher than that of hybrid lines,and♀‘Haixuan No.1’×♂‘Haiyou No.1’maintained a high survival rate during the grow-out stage.The shell length and width were affected by the genotypes as well as the interaction between the genotypes and environmental factors on day 400.The variances of the general combining abilities(GCA)and specific combining abilities(SCA)for shell length and width were the result of both additive genetic variance and nonadditive genetic variance.When Haixuan No.1 was the female parent and Nanke No.1 was the male parent,the GCA for shell length and width were both positive on day 400.The heterosis of Haixuan No.1 and Nanke No.1 in terms of shell length and width was positive.From the resulting combining ability and heterosis,♀‘Haixuan No.1’×♂‘Nanke No.1’was considered an ideal hatchery method to improve the growth performance of P.martensii.Our results therefore demonstrated that crossbreeding among these three new varieties can further improve the growth performance of P.martensii.展开更多
Inhibitory Smads(I-Smads),which belong to the Smad family and inhibit bone morphogenic protein 2(BMP2)signaling by a variety of mechanisms,can suppress innate immunity responses in vertebrates.However,there are no rep...Inhibitory Smads(I-Smads),which belong to the Smad family and inhibit bone morphogenic protein 2(BMP2)signaling by a variety of mechanisms,can suppress innate immunity responses in vertebrates.However,there are no reports for the role of Smad6 in immunity in mollusks.In this study,we showed that Smad6 of the pearl oyster Pinctada fucata martensii was located in the Smad6 cluster of the phylogenetic tree;mRNA expression of Smad6 and Smad3 was up-regulated after lipopolysaccharide and polyinosinic:polycytidylic challenge;and transcript levels of Smad6 and Smad3 showed opposite patterns during wound healing.Under salinity stress,water inflow and outflow in the gills appear to be regulated by BMP2-Smads signals,and BMP2-Smads signaling may be closely related to the immune response.Our results indicate that Smad6 is involved in immunity,that it plays a positive role in the response to immune challenge and an inhibitory role during wound healing,and that Smad6 and Smad3 may work against each other.展开更多
The pearl oyster Pinctada fucata martensii is an economically valuable shellfish that is cultured for seawater pearl pro-duction,which mainly depends on oyster growth.However,the growth mechanisms of the pearl oyster ...The pearl oyster Pinctada fucata martensii is an economically valuable shellfish that is cultured for seawater pearl pro-duction,which mainly depends on oyster growth.However,the growth mechanisms of the pearl oyster are still poorly understood.In this study,oysters were grouped with relative growth rate,including fast-growing(FG)group and slow-growing(SG)group.Oxford Nanopore Technologies(ONT)long-read sequencing was applied to investigate the molecular mechanisms involved in the growth of this species.Five alternative splicing(AS)types were analyzed in both FG and SG groups,which include alternative 3’splice site,alternative 5’splice site,exon skipping,intron retention,and mutually exclusive exon.Transcriptome analysis showed that four of five different AS events(excluding mutually exclusive exons)occurred more frequently in FG than in SG oysters,and the five main AS types exhibited different characteristics.The AS events that were detected may be involved in growth,and the difference in ex-pression of AS events between FG and SG oysters may be involved in the mechanism underlying the difference in growth.Fifty dif-ferentially expressed genes(DEGs)were identified between the FG and SG oysters.The results showed that 40 genes were signifi-cantly up-regulated in FG oysters,while 10 genes were significantly down-regulated in SG oyster.Several genes related to nutrient metabolism,shell formation,and immunity were more highly expressed in FG oysters than in SG oysters.In summary,FG oysters exhibited higher metabolic and biomineralization activities and had a more powerful immune system than SG oysters.These results provide insight into the growth of P.f.martensii that can be used to improve breeding programs.展开更多
Differentially expressed genes(DEGs)between individuals with high(HC)and low(LC)total carotenoid content(TCC)were sampled from a selected line of Pinctada fucata martensii with black shell in the prismatic layer.The e...Differentially expressed genes(DEGs)between individuals with high(HC)and low(LC)total carotenoid content(TCC)were sampled from a selected line of Pinctada fucata martensii with black shell in the prismatic layer.The expression levels of candidate genes were verified by qRT-PCR.Targeted resequencing was used to detect SNPs in a candidate gene,PmSR-BI.The association of TCC with SNPs in PmSR-BI was determined.Results showed that a total of 1025 DEGs were identified between HC and LC.The expression levels of the candidate gene PmSR-BI in HC were higher than those in LC.Seven SNPs in the exon and eight SNPs in the 5′regulatory regions of PmSR-BI were found.Association analysis showed that one SNP in the exon and two SNPs in the 5′regulatory regions of PmSR-BI were significantly associated with the TCC(P<0.05).All SNPs of PmSR-BI were divided into four blocks.CC haplotype in Block 1 and AG haplotype in Block 3 were significantly higher than other haplotypes.These results help elucidate the mechanism underlying carotenoid metabolism and develop marker-assisted breeding design in the species.展开更多
基金supported by the Science and Technology Program of Guangdong Province (No.2022A1515010030)the National Natural Science Foundation of China (No.32102817)+3 种基金the Program for Sientific Research Start-up Funds of Guangdong Ocean University (No.060302022304)the Department of Education of Guangdong Province (Nos.2020ZDZX1045 and 2021KCXTD026)the Earmarked Fund for CARS-49the Guangdong Provincial Special Fund for Modern Agriculture Industry Technology Innovation Teams (No.2023KJ146)。
文摘The yellow-colored line of pearl oyster Pinctada fucata martensii displays a yellow prismatic layer and a white nacreous layer that can be used as an ideal model for research on shell color formation.Micro-Raman spectroscopy and transcriptome analyses were performed to explore the potential molecular mechanism underlying the phenotype differentiation.The micro-Raman spectroscopy results indicate that the prismatic layer exhibits distinct characteristic peaks of carotenoids,while these peaks are not prominent in the nacreous layer.In the transcriptome comparison of the central zone of mantle and mantle edge tissue,which function in nacreous and prismatic layer formation,respectively,935 significantly differentially expressed genes(DEGs)were identified,with 385 genes upregulated and 227 genes downregulated(|log_(2)(Fold change)|>1 and false discovery rate<0.05)in the mantle edge tissue.Among these genes,some were associated with melanoma/melanogenesis,such as tyrosinase,zinc metalloprotease,glutathione S-transferase,and ATP-binding cassette sub-family;some were associated with the carotenoid-related pathway,including scavenger receptors,cytochrome P450 and lipoprotein receptor.Genes associated with porphyrin metabolism,including porphobilinogen deaminase,and copper/zinc superoxide dismutase,and genes associated with shell matrix protein,including amorphous calcium carbonate binding protein,shematrin,PIF,and collagen,also exhibited significantly different expressions.It is speculated that the different colours between prismatic layer and nacreous layer in the yellow-colored line of P.f.martensii might be resulted from melanin,carotenoids and porphyrin metabolism,while genes related to shell structure and biomineralization might also affect coloration.Our results provide new insights to understand the mechanism of shell color formation in mollusca.
基金supported by the"863"Project in China(#863-819-01-03)the Natural Science Foundation of Guangdong,China(#990315).
文摘Aneuploidy embryos of Pinctada martensii Dunker are produced during tetraploid induction by inhibiting the first polar body in eggs from triploid fertilized with haploid sperms with cytochalasin B treatment. Chromosome analysis reveals that there are 88.18 ±6.79% aneuploidy embryos, and 28.70% aneuploids in pearl oysters of one-year age These aneuploids have five chromosomal conditions, such as 2n + 1(29), 2n + 2 (30), 3n-2 (40), 3n-1(41) and 3n + 1 (43). Results of growth measurement show that there is no significant difference between aneuploids (as a group) and diploids in body size and weight (p ＞ 0.10), but the aneuploide is obviously different from triploid (p ＜ 0.01). The mean body size and weight of aneuploids in diploid condition (2n ± 1 and 2n ± 2) are significantly smaller than those of diploids (p ＜ 0.01),but aneuploids within triploid condition (3n ± 1 and 3n ± 2) are not smaller than diploids in body size and weight (p ＞ 0.1).This study indicates Pinctada martensii Dunker could tolerate aneuploidy by 7 ～ 14% of the haploid genome, and that aneuploids of this species are viable under certain conditions.
基金grants of the Guangdong Marine and Fishery Bureau(No.B02068)Guangdong Ocean University(No.E06031).
文摘120 pearl oysters （Pinctada martensii） were randomly sampled from F1 population, and shell length, shell width, shell height, shell weight and total weight of each sample were measured. Correlation and path analysis were conducted on the basis of measurement data. The results showed that shell length, shell width, shell height, shell weight and total weight were significantly correlated （P 〈 0.05）. Total weight was significantly and positively correlated with shell weight （r = 0.8970）, shell height （r = 0.6974）, shell width （r = 0.6521） and shell length （r = 0.5486）. Shell weight, shell height, shell width and shell length had positive and direct effects on total wet weight, with the values of 0.6356, 0.1872, 0.1814 and 0.0599, respectively. The results indicated that growth traits （shell length, shell width, shell height, shell weight and total wet weigh） of the F1 population could be improved by direct or indirect selection.
基金The National Key Technology R&D Program in the 11th Five Year Plan of China under contract No. 2007BAD29B01-2National Department Public Benefit Research Foundation under contract No. nyhyzx 07-048Guangdong Marine and Fishery Bureau under contract Nos A200708C01, A200908A02 and A200908A05
文摘In May of 2007,the second generation selected （SS） and control （SC） groups of pearl oyster Pinctada martensii were established by selecting 10% breeders with the largest and mean shell length,respectively,from the first generation selected group.Growth performance of the SS and SC groups were compared on the basis of measurement data at Days 8,18,60,95,195 and 365.On Day 365,100 individuals （60.0–75.0 mm at shell length） were sampled from each group and then subjected to the experiment where physiological parameters such as filtrate rate,oxygen consumption and ammonia excretion were measured at 15,20,25 and 30°C.The results show that the SS group had significantly larger mean shell length and shell height than the SC group at Days 8,18,60,95,195 and 365 （P 0.05）.The genetic gains at different ages varied from 6.0% to 17.0% for shell length and 5.7% to 14.6% for shell height,respectively.At 15,20,25 and 30 ° C,the SS groups had significantly larger filtrate rate than the SC group （P 0.05）.At 15 and 25 °C,the differences in oxygen consumption rate between the SS and SC groups were not significant （P 0.05）.At 20 and 30 °C,however,the oxygen consumption rate of the SS group was significantly larger than the SC group （P 0.05）.At 15,20,25 and 30 °C,there were no significant differences in ammonia excretion rate between the SS and SC groups （P 0.05）.The present results indicate that there existed considerable genetic variability in the base population and a further selection could be likely fruitful.Mass selection for faster growth might produce animals that had higher intake of metabolizable energy by virtue of faster filtrating behavior.
基金supported by National Key Technologies R&D Program of China(2008 BAD94B08)
文摘The present study investigated the removal of inorganic arsenic from Pinctada martensii enzymatic hydrolysate through unmodified resin （D296） and Zr（IV）-loaded chelating resin （Zr-D401）. By loading Zr to macroporous chelating resin D401, the as exchange adsorption active sites are generated. This transforms D401 from a material that does not have the arsenic adsorption capacity into a material that has excellent arsenic exchange adsorption capacity. The static adsorption experiments were conducted to investigate the optimal removal condition for D296 and Zr-D401. The experimental results show that： the optimum condition for D296 is that T= 25℃, pH= 5, resin additive amount= 1 g （50 mL）-1, and contact time = 10 h, the corresponding arsenic removal rate being 65.7%, and protein loss being 2.33%; the optimum condition for Zr-D401 is that T=25 ℃, pH = 8, resin additive amount= 1 g （50 mL）-1, and contact time=10 h, the corresponding arsenic removal rate being 70.3%, and protein loss being 4.65%. These results show that both of the two resins are effective in arsenic removal for preserving useful substance. Our research provides scientific evidence and advances in the processing technology for heavy metal removal in shellfish.
基金Supported by the Comprehensive Strategic Cooperation Programs between Guangdong Province and Chinese Academy of Sciences(No.2011A090100008)the Knowledge Innovation Program of Chinese Academy of Sciences(No.KZCX2-EW-Q214)
文摘A new enzyme (alkaline protease 894) obtained from the marine extremophile Flavobacterium yellowsea (YS-80-122) has exhibited strong substrate-binding and catalytic activity, even at low temperature, but the characteristics of the hydrolysis with this enzyme are still unclear. The pearl oyster Pinctada martensii was used in this study as the raw material to illustrate the kinetic properties of protease 894. After investigating the intrinsic relationship between the degree of hydrolysis and several factors, including initial reaction pH, temperature, substrate concentration, enzyme concentration, and hydrolysis time, the kinetics model was established. This study showed that the optimal conditions for the enzymatic hydrolysis were an initial reaction pH of 5.0, temperature of 30°C, substrate concentration of 10% (w/v), enzyme concentration of 2 500 U/g, and hydrolysis time of 160 min. The kinetic characteristics of the protease for the hydrolysis of P. martensii were obtained. The inactivation constant was found to be 15.16/min, and the average relative error between the derived kinetics model and the actual measurement was only 3.04%, which indicated a high degree of fitness. Therefore, this study provides a basis for the investigation of the concrete kinetic characteristics of the new protease, which has potential applications in the food industry.
基金funded by the National Natural Science Foundation of China(No.911221680).
文摘Pinctada martensii is an important shellfish for the production of sea pearls in China.To improve the growth performance of P.martensii,we successfully established three complete diallel crosses using three new varieties of P.martensii,which were named Haiyou No.1,Haixuan No.1,and Nanke No.1,to investigate the growth performance of each self-cross line and hybrid line in Beihai,Guangxi Zhuang Autonomous Region,China.Generally,high fertilization and hatching rates were observed in the experiment,suggesting that there was no sperm-egg recognition barrier among these three P.martensii varieties.The survival rate of the self-cross lines was relatively higher than that of hybrid lines,and♀‘Haixuan No.1’×♂‘Haiyou No.1’maintained a high survival rate during the grow-out stage.The shell length and width were affected by the genotypes as well as the interaction between the genotypes and environmental factors on day 400.The variances of the general combining abilities(GCA)and specific combining abilities(SCA)for shell length and width were the result of both additive genetic variance and nonadditive genetic variance.When Haixuan No.1 was the female parent and Nanke No.1 was the male parent,the GCA for shell length and width were both positive on day 400.The heterosis of Haixuan No.1 and Nanke No.1 in terms of shell length and width was positive.From the resulting combining ability and heterosis,♀‘Haixuan No.1’×♂‘Nanke No.1’was considered an ideal hatchery method to improve the growth performance of P.martensii.Our results therefore demonstrated that crossbreeding among these three new varieties can further improve the growth performance of P.martensii.
基金Supported by the Natural Science Foundation of Guangdong Province,China(No.2019A1515011968)the Key Special Project for Introduced Talents Team of the Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(No.GML2019ZD0401)+1 种基金the Earmarked Fund for the Modern Agro-industry Technology Research System(No.CARS-49)the Science and Technology Planning Project of Guangdong Province,China(No.2020B1212060058)。
文摘Inhibitory Smads(I-Smads),which belong to the Smad family and inhibit bone morphogenic protein 2(BMP2)signaling by a variety of mechanisms,can suppress innate immunity responses in vertebrates.However,there are no reports for the role of Smad6 in immunity in mollusks.In this study,we showed that Smad6 of the pearl oyster Pinctada fucata martensii was located in the Smad6 cluster of the phylogenetic tree;mRNA expression of Smad6 and Smad3 was up-regulated after lipopolysaccharide and polyinosinic:polycytidylic challenge;and transcript levels of Smad6 and Smad3 showed opposite patterns during wound healing.Under salinity stress,water inflow and outflow in the gills appear to be regulated by BMP2-Smads signals,and BMP2-Smads signaling may be closely related to the immune response.Our results indicate that Smad6 is involved in immunity,that it plays a positive role in the response to immune challenge and an inhibitory role during wound healing,and that Smad6 and Smad3 may work against each other.
基金supported by the Earmarked Fund for the China Agriculture Research System(No.CARS-49)the Science and Technology Planning Project of Guang-dong Province,China(No.No2020B1212060058).
文摘The pearl oyster Pinctada fucata martensii is an economically valuable shellfish that is cultured for seawater pearl pro-duction,which mainly depends on oyster growth.However,the growth mechanisms of the pearl oyster are still poorly understood.In this study,oysters were grouped with relative growth rate,including fast-growing(FG)group and slow-growing(SG)group.Oxford Nanopore Technologies(ONT)long-read sequencing was applied to investigate the molecular mechanisms involved in the growth of this species.Five alternative splicing(AS)types were analyzed in both FG and SG groups,which include alternative 3’splice site,alternative 5’splice site,exon skipping,intron retention,and mutually exclusive exon.Transcriptome analysis showed that four of five different AS events(excluding mutually exclusive exons)occurred more frequently in FG than in SG oysters,and the five main AS types exhibited different characteristics.The AS events that were detected may be involved in growth,and the difference in ex-pression of AS events between FG and SG oysters may be involved in the mechanism underlying the difference in growth.Fifty dif-ferentially expressed genes(DEGs)were identified between the FG and SG oysters.The results showed that 40 genes were signifi-cantly up-regulated in FG oysters,while 10 genes were significantly down-regulated in SG oyster.Several genes related to nutrient metabolism,shell formation,and immunity were more highly expressed in FG oysters than in SG oysters.In summary,FG oysters exhibited higher metabolic and biomineralization activities and had a more powerful immune system than SG oysters.These results provide insight into the growth of P.f.martensii that can be used to improve breeding programs.
基金The research was financially supported by Science and Technology Program of Guangdong Province(Grant No.2021B0202020003,and 2022A1515010030)National Natural Science Foundation of China(Grant No.32102817)+2 种基金Department of Education of Guangdong Province(Grant No.2019KQNCX043,2020ZDZX1045 and 2021KCXTD026)Special promotion of fishery science and technology of Ocean and Fisheries Bureau of Guangdong Province(Grant No.B201601-Z09)the earmarked fund for CARS-49.
文摘Differentially expressed genes(DEGs)between individuals with high(HC)and low(LC)total carotenoid content(TCC)were sampled from a selected line of Pinctada fucata martensii with black shell in the prismatic layer.The expression levels of candidate genes were verified by qRT-PCR.Targeted resequencing was used to detect SNPs in a candidate gene,PmSR-BI.The association of TCC with SNPs in PmSR-BI was determined.Results showed that a total of 1025 DEGs were identified between HC and LC.The expression levels of the candidate gene PmSR-BI in HC were higher than those in LC.Seven SNPs in the exon and eight SNPs in the 5′regulatory regions of PmSR-BI were found.Association analysis showed that one SNP in the exon and two SNPs in the 5′regulatory regions of PmSR-BI were significantly associated with the TCC(P<0.05).All SNPs of PmSR-BI were divided into four blocks.CC haplotype in Block 1 and AG haplotype in Block 3 were significantly higher than other haplotypes.These results help elucidate the mechanism underlying carotenoid metabolism and develop marker-assisted breeding design in the species.
