Polychaetes provide an excellent food resource for fi sh and represent the dominant zoobenthos in marine ecosystems. Diel variation in the rates of metabolism and ammonia-N excretion of Marphysa sanguinea were studied...Polychaetes provide an excellent food resource for fi sh and represent the dominant zoobenthos in marine ecosystems. Diel variation in the rates of metabolism and ammonia-N excretion of Marphysa sanguinea were studied. The worms were grouped according to their wet body weight into small(S; 1.24±0.06 g), medium(M; 4.00±0.30 g), and large(L; 8.54±1.08 g) categories. Their weight-specifi c metabolic rates, based on aerobic respiration( R), were measured at 16°C(±0.2°C) and classed as either routine( R_R) or standard( R_S) rates. Both respiration types decreased with increasing body weight. Respiration was described by R = a W^b, where b was-0.400 9 and-0.532 0 for R_R and R_S, respectively. Diurnal changes in R_S for each group was relatively flat, with a slightly increasing trend with time, but was relatively stable as a whole. R_R of the diurnal variation of worms was higher than R_S, but both had similar overall trends. The peak values of specifi c dynamic action(SDA)( R_(SDA)) in the S, M, and L groups were 2.704, 1.149, and 0.682 mg/(g?h), respectively. The durations of SDA were 13, 6, and 6 h, respectively and the energy expenditures of SDA were 377.98, 117.34, and 74.94 J/g, respectively. These data indicate that the metabolic rates were higher in smaller individuals, which is advantageous for their rapid growth.展开更多
Rapid amplification of cDNA ends (RACE) and real-time polymerase chain reaction (RT-PCR) were carried out to analyze the CYP4 gene expression in polychaete Marphysa sanguinea exposed to benzo[a]pyrene (BaP) in this st...Rapid amplification of cDNA ends (RACE) and real-time polymerase chain reaction (RT-PCR) were carried out to analyze the CYP4 gene expression in polychaete Marphysa sanguinea exposed to benzo[a]pyrene (BaP) in this study. The full length of MsCYP4 cDNA was 2 470 bp, and it encoded 512 amino acids. The deduced amino acid sequence showed 47% identity with CYP4F from frog Xenopus tropicalis and shared high homology with other known CYP4 sequences. To analyse the role of CYP4 in protecting M. sanguinea from BaP exposure, three BaP groups were established: 0.5, 5 and 50 μg/L. Polychaetes were sampled after 3, 7 and 12 d. At 0.5 μg/L, the effect of BaP on MsCYP4 gene expression increased with time prolonged. MsCYP4 gene expression curve showed Ushaped trend with time in 5 and 50 μg/L BaP groups. Therefore, MsCYP4 gene may play an important role in maintaining the balance of cellular metabolism and protecting M. sanguinea from BaP toxicity.展开更多
基金Supported by the National Natural Science Foundation of China(No.30901107)the National Marine Public Welfare Research Project(Nos.201305002,201305043)the Project of Marine Ecological Restoration Technology Research to the Penglai 19-3 Oil Spill Accident(No.19-3YJ09)
文摘Polychaetes provide an excellent food resource for fi sh and represent the dominant zoobenthos in marine ecosystems. Diel variation in the rates of metabolism and ammonia-N excretion of Marphysa sanguinea were studied. The worms were grouped according to their wet body weight into small(S; 1.24±0.06 g), medium(M; 4.00±0.30 g), and large(L; 8.54±1.08 g) categories. Their weight-specifi c metabolic rates, based on aerobic respiration( R), were measured at 16°C(±0.2°C) and classed as either routine( R_R) or standard( R_S) rates. Both respiration types decreased with increasing body weight. Respiration was described by R = a W^b, where b was-0.400 9 and-0.532 0 for R_R and R_S, respectively. Diurnal changes in R_S for each group was relatively flat, with a slightly increasing trend with time, but was relatively stable as a whole. R_R of the diurnal variation of worms was higher than R_S, but both had similar overall trends. The peak values of specifi c dynamic action(SDA)( R_(SDA)) in the S, M, and L groups were 2.704, 1.149, and 0.682 mg/(g?h), respectively. The durations of SDA were 13, 6, and 6 h, respectively and the energy expenditures of SDA were 377.98, 117.34, and 74.94 J/g, respectively. These data indicate that the metabolic rates were higher in smaller individuals, which is advantageous for their rapid growth.
基金The Dalian Science Fund for Distinguished Young Scholars under contract No.2016RJ06the Natural Science Foundation of Liaoning Province under contract No.201602107+1 种基金the Superior College Science Technology Research Project of Liaoning Province under contract No.ZL201701the National Natural Science Foundation of China under contract No.41306138
文摘Rapid amplification of cDNA ends (RACE) and real-time polymerase chain reaction (RT-PCR) were carried out to analyze the CYP4 gene expression in polychaete Marphysa sanguinea exposed to benzo[a]pyrene (BaP) in this study. The full length of MsCYP4 cDNA was 2 470 bp, and it encoded 512 amino acids. The deduced amino acid sequence showed 47% identity with CYP4F from frog Xenopus tropicalis and shared high homology with other known CYP4 sequences. To analyse the role of CYP4 in protecting M. sanguinea from BaP exposure, three BaP groups were established: 0.5, 5 and 50 μg/L. Polychaetes were sampled after 3, 7 and 12 d. At 0.5 μg/L, the effect of BaP on MsCYP4 gene expression increased with time prolonged. MsCYP4 gene expression curve showed Ushaped trend with time in 5 and 50 μg/L BaP groups. Therefore, MsCYP4 gene may play an important role in maintaining the balance of cellular metabolism and protecting M. sanguinea from BaP toxicity.
