Thirty nine isozymes in four tissues (mantle muscle, buccal bulb muscle, eye and liver) of Sepia esculenta were screened for enzymatic analysis using starch gel electrophoretic technique. Eighteen enzymes (G3PDH, LDH,...Thirty nine isozymes in four tissues (mantle muscle, buccal bulb muscle, eye and liver) of Sepia esculenta were screened for enzymatic analysis using starch gel electrophoretic technique. Eighteen enzymes (G3PDH, LDH, MDH, MEP, IDHP, PGDH, GRS, NP, AAT, CK, AK, EST, ALP, ACP, FBP, MPI, GPI and PGM) show strong activities and good convergence in zymogram. They are proved to be suitable genetic markers in Sepia esculenta. Among the tissues used, mantle muscle is the best for electrophoretic analysis of isozymes. Eye and liver are fairly good for some special enzymes, such as LDH, EST, MPI, etc. Twenty six loci are detected. The proportion of polymorphic loci is 0.115 in the Qingdao sample and 0.153 in the Rizhao sample ( P < 0.99 ). The mean values of the observed and expected heterozygosity per locus of Qingdao sample are 0.016 and 0.017 , while those of the Rizhao sample are 0.023 and 0.025 respectively.展开更多
The morphological characteristics and the cuttlebone formation of Sepia esculenta exposed to different water temperature fluctuations were investigated under laboratory conditions. Temperature fluctuation cycles (15 c...The morphological characteristics and the cuttlebone formation of Sepia esculenta exposed to different water temperature fluctuations were investigated under laboratory conditions. Temperature fluctuation cycles (15 cycles, 60 d in total) consisted of the following three regimes of 4 d duration: keeping water temperature in 26°C for 3 d (Group A), 2 d (Group B), 0 d (Group C, control); then keeping water temperature in 16°C for the next 1, 2, 4 d. No significant difference in the survival rate was observed between the control and temperature fluctuation groups (P>0.05). Lamellar depositions in a temperature fluctuation cycle were 2.45±0.02 for Group A, 2.00±0.02 for Group B, and 1.78±0.02 for Group C (P<0.05). The relationship between age and number of lamellas in the cuttlebone of S. esculenta under each water temperature fluctuation could be described as the linear model and the number of lamellas in the cuttlebone did not correspond to actual age. Group A had the highest cuttlebone growth index (CGI), the lowest locular index (LI), and inter-streak distances comparing with those of control group. However, the number of lamellas and LI or CGI showed a quadratic relationship for each temperature fluctuation group. In addition, temperature fluctuations caused the breakage of cuttlebone dark rings, which was considered a thermal mark. The position of the breakage in the dark rings was random. This thermal mark can be used as supplementary information for marking and releasing techniques.展开更多
The secretion function of mantle is closely related to shell formation in some bivalves and gastropods. Up to now, few researches have been reported for cuttlebone formation in the class Cephalopoda. In this study, th...The secretion function of mantle is closely related to shell formation in some bivalves and gastropods. Up to now, few researches have been reported for cuttlebone formation in the class Cephalopoda. In this study, the structure and secretion function of cuttlebone sac of the golden cuttlefish Sepia esculenta was analyzed using the histological and histochemical methods. The results showed that high and columnar cells located in sac epithelium, and flat cells existed near the base membrane. A lot of fibroblasts were found in the lateral mantle collective tissue. Some mucus, mucopolysaccharide and alkaline phosphatase (ALP) were found in the sac. The ultrastructural characteristics of Quasi-connective-tissue-calcium cells (QCTCC) were observed using a transmission electron microscope (TEM). The relationship between cuttlebone sac secretion function and shell formation was discussed.展开更多
The distribution of chitinolytic enzymes in eight organs of the golden cuttlefish Sepia esculenta was determined. Chitinase activity (activity of endo-type chitinolytic enzyme) was measured using pNP-(GlcNAc)n (n = 2,...The distribution of chitinolytic enzymes in eight organs of the golden cuttlefish Sepia esculenta was determined. Chitinase activity (activity of endo-type chitinolytic enzyme) was measured using pNP-(GlcNAc)n (n = 2, 3) as substrates, with high activity detected in the liver, posterior salivary gland, and stomach. β-N-acetylhexosaminidase (Hex) activity (activity of exo-type chitinolytic enzyme) was determined using pNP-(GlcNAc) as a substrate, and high activity was observed in six organs, including the liver, branchial heart, posterior salivary gland, and stomach. In addition, two chitin-binding proteins (CBP-A, CBP-B) were isolated from the liver using a chitin affinity column. Two full-length cDNAs (SeChi-1: 1484 bp;SeChi-2: 1748 bp) encoding chitinases were obtained from the liver of S. esculenta. SeChi-1 contained a 1377-bp open reading frame (ORF) encoding 459 amino acids, and SeChi-2 contained a 1656-bp ORF encoding 552 amino acids. Domain structures predicted from the deduced amino acid sequences of SeChi-1 and SeChi-2 (SeChi-1, SeChi-2) contained signal peptides, a GH Family 18 catalytic domain, one chitin binding domain (CBD) in SeChi-1, and two CBDs in SeChi-2. Proteome analysis revealed that 125 peptide residues of CBP-A were present in SeChi-1, and 116 peptide residues of CBP-B were present in SeChi-2. Organ expression analysis revealed that SeChi-1 and SeChi-2 were expressed only in the liver of S. esculenta. Phylogenetic analysis of SeChi-1, SeChi-2, and GH family 18 chitinases revealed that SeChi-2 belongs to a group of previously reported squid chitinases, while SeChi-1 does not belong to any previously reported group of mollusk chitinases.展开更多
With the rapid development of oil,energy,power and other industries,CO_(2) emissions rise sharply,which will cause a large amount of CO_(2) in the air be absorbed by the ocean and lead to ocean acidification.The growt...With the rapid development of oil,energy,power and other industries,CO_(2) emissions rise sharply,which will cause a large amount of CO_(2) in the air be absorbed by the ocean and lead to ocean acidification.The growth and development of organisms can be seriously affected by acidified seawater.Sepia esculenta is a mollusk with high nutritional and economic value and is widely cultured in offshore waters of China.Larvae are the early life forms of the organism and are more vulnerable to changes in the external environment.Too low pH will lead to some adverse reactions in larvae,which will affect metabolism,immune response and other life activities.In this study,we sequenced the transcriptome of S.esculenta subjected to acidified seawater stress and identified 1072differentially expressed genes(DEGs).The detected atypical expression of DEGs substantiates cellular malformation and translocation in S.esculenta under low pH stimulation.Simultaneously,this also substantiates the notable impact of ocean acidification on mollusks.These DEGs were used for functional enrichment analysis of GO and KEGG,and the top twenty items of the biological process classification in GO terms and 11 KEGG signaling pathways were significantly enriched.Finally,the constructed proteinprotein interaction network(PPI)was used to analyze protein-protein interactions,and 12 key DEGs and 3 hub genes were identified.The reliability of 12 genes was verified by quantitative RT-PCR.A comprehensive analysis of the KEGG signaling pathway and PPI revealed that ocean acidification leads to abnormalities in lipid metabolism in S.esculenta larvae,which can lead to cancer development and metastasis,accompanied by some degree of inflammation.The results of the study will help to further investigate the physiological processes of S.esculenta when stimulated by ocean acidification,and provide a reference to cope with the captive breeding of S.esculenta affected by acidification.展开更多
文摘Thirty nine isozymes in four tissues (mantle muscle, buccal bulb muscle, eye and liver) of Sepia esculenta were screened for enzymatic analysis using starch gel electrophoretic technique. Eighteen enzymes (G3PDH, LDH, MDH, MEP, IDHP, PGDH, GRS, NP, AAT, CK, AK, EST, ALP, ACP, FBP, MPI, GPI and PGM) show strong activities and good convergence in zymogram. They are proved to be suitable genetic markers in Sepia esculenta. Among the tissues used, mantle muscle is the best for electrophoretic analysis of isozymes. Eye and liver are fairly good for some special enzymes, such as LDH, EST, MPI, etc. Twenty six loci are detected. The proportion of polymorphic loci is 0.115 in the Qingdao sample and 0.153 in the Rizhao sample ( P < 0.99 ). The mean values of the observed and expected heterozygosity per locus of Qingdao sample are 0.016 and 0.017 , while those of the Rizhao sample are 0.023 and 0.025 respectively.
基金Supported by the National High Technology Research and Development Program of China (863 Program) (No. 2010AA10A404)the National Marine Public Welfare Research Project (No. 200805069)the NMOE Project (No. 1011010603)
文摘The morphological characteristics and the cuttlebone formation of Sepia esculenta exposed to different water temperature fluctuations were investigated under laboratory conditions. Temperature fluctuation cycles (15 cycles, 60 d in total) consisted of the following three regimes of 4 d duration: keeping water temperature in 26°C for 3 d (Group A), 2 d (Group B), 0 d (Group C, control); then keeping water temperature in 16°C for the next 1, 2, 4 d. No significant difference in the survival rate was observed between the control and temperature fluctuation groups (P>0.05). Lamellar depositions in a temperature fluctuation cycle were 2.45±0.02 for Group A, 2.00±0.02 for Group B, and 1.78±0.02 for Group C (P<0.05). The relationship between age and number of lamellas in the cuttlebone of S. esculenta under each water temperature fluctuation could be described as the linear model and the number of lamellas in the cuttlebone did not correspond to actual age. Group A had the highest cuttlebone growth index (CGI), the lowest locular index (LI), and inter-streak distances comparing with those of control group. However, the number of lamellas and LI or CGI showed a quadratic relationship for each temperature fluctuation group. In addition, temperature fluctuations caused the breakage of cuttlebone dark rings, which was considered a thermal mark. The position of the breakage in the dark rings was random. This thermal mark can be used as supplementary information for marking and releasing techniques.
基金This study was supported by the grants from the National Natural Science Foundation of China （No. 30600463）the Key Laboratory of Mariculture of Ministry of Education, 0cean University of China （No. 200610）.
文摘The secretion function of mantle is closely related to shell formation in some bivalves and gastropods. Up to now, few researches have been reported for cuttlebone formation in the class Cephalopoda. In this study, the structure and secretion function of cuttlebone sac of the golden cuttlefish Sepia esculenta was analyzed using the histological and histochemical methods. The results showed that high and columnar cells located in sac epithelium, and flat cells existed near the base membrane. A lot of fibroblasts were found in the lateral mantle collective tissue. Some mucus, mucopolysaccharide and alkaline phosphatase (ALP) were found in the sac. The ultrastructural characteristics of Quasi-connective-tissue-calcium cells (QCTCC) were observed using a transmission electron microscope (TEM). The relationship between cuttlebone sac secretion function and shell formation was discussed.
文摘The distribution of chitinolytic enzymes in eight organs of the golden cuttlefish Sepia esculenta was determined. Chitinase activity (activity of endo-type chitinolytic enzyme) was measured using pNP-(GlcNAc)n (n = 2, 3) as substrates, with high activity detected in the liver, posterior salivary gland, and stomach. β-N-acetylhexosaminidase (Hex) activity (activity of exo-type chitinolytic enzyme) was determined using pNP-(GlcNAc) as a substrate, and high activity was observed in six organs, including the liver, branchial heart, posterior salivary gland, and stomach. In addition, two chitin-binding proteins (CBP-A, CBP-B) were isolated from the liver using a chitin affinity column. Two full-length cDNAs (SeChi-1: 1484 bp;SeChi-2: 1748 bp) encoding chitinases were obtained from the liver of S. esculenta. SeChi-1 contained a 1377-bp open reading frame (ORF) encoding 459 amino acids, and SeChi-2 contained a 1656-bp ORF encoding 552 amino acids. Domain structures predicted from the deduced amino acid sequences of SeChi-1 and SeChi-2 (SeChi-1, SeChi-2) contained signal peptides, a GH Family 18 catalytic domain, one chitin binding domain (CBD) in SeChi-1, and two CBDs in SeChi-2. Proteome analysis revealed that 125 peptide residues of CBP-A were present in SeChi-1, and 116 peptide residues of CBP-B were present in SeChi-2. Organ expression analysis revealed that SeChi-1 and SeChi-2 were expressed only in the liver of S. esculenta. Phylogenetic analysis of SeChi-1, SeChi-2, and GH family 18 chitinases revealed that SeChi-2 belongs to a group of previously reported squid chitinases, while SeChi-1 does not belong to any previously reported group of mollusk chitinases.
基金funded by the Ministry of Agriculture of the People’s Republic of China (No.CARS-49)。
文摘With the rapid development of oil,energy,power and other industries,CO_(2) emissions rise sharply,which will cause a large amount of CO_(2) in the air be absorbed by the ocean and lead to ocean acidification.The growth and development of organisms can be seriously affected by acidified seawater.Sepia esculenta is a mollusk with high nutritional and economic value and is widely cultured in offshore waters of China.Larvae are the early life forms of the organism and are more vulnerable to changes in the external environment.Too low pH will lead to some adverse reactions in larvae,which will affect metabolism,immune response and other life activities.In this study,we sequenced the transcriptome of S.esculenta subjected to acidified seawater stress and identified 1072differentially expressed genes(DEGs).The detected atypical expression of DEGs substantiates cellular malformation and translocation in S.esculenta under low pH stimulation.Simultaneously,this also substantiates the notable impact of ocean acidification on mollusks.These DEGs were used for functional enrichment analysis of GO and KEGG,and the top twenty items of the biological process classification in GO terms and 11 KEGG signaling pathways were significantly enriched.Finally,the constructed proteinprotein interaction network(PPI)was used to analyze protein-protein interactions,and 12 key DEGs and 3 hub genes were identified.The reliability of 12 genes was verified by quantitative RT-PCR.A comprehensive analysis of the KEGG signaling pathway and PPI revealed that ocean acidification leads to abnormalities in lipid metabolism in S.esculenta larvae,which can lead to cancer development and metastasis,accompanied by some degree of inflammation.The results of the study will help to further investigate the physiological processes of S.esculenta when stimulated by ocean acidification,and provide a reference to cope with the captive breeding of S.esculenta affected by acidification.
