Fish embryos are widely used as models in toxicology,drug development,and human disease research because of their high sensitivity,observability,and operability,providing the basis for an in-depth understanding of the...Fish embryos are widely used as models in toxicology,drug development,and human disease research because of their high sensitivity,observability,and operability,providing the basis for an in-depth understanding of the embryogenesis.Increasing studies have indicated that birth defects are hereditary.In this study,we used Oryzias melastigma as a model to conduct a study of 185-day embryogenesis and observed self-induced non-pathological abnormal embryogenesis.O.melastigma experienced pre-puberty stage,adolescence stage,and senescence stage,and individuals produced up to 102 eggs per day.However,the fecundity was markedly reduced during the senescent stage.During the active egg and blastodisc stages,pseudo-fertilization and pseudo-blastocysts were observed.During cleavage at the 4-to 32-cell stages,we observed blastomeres separation or dislocation.Excessively separated blastomeres formed double blastoderms,eventually resulting in conjoined twins.During the blastula stage,we observed abnormally increased cell volume,narrowed and elongated blastocysts,and abnormally coated blastoderms.At the organogenesis stage,we observed abnormal numbers of Kupff er’s vesicles and conjoined twins.Abnormality in the location and number of oil droplets were observed in various development stages.Abnormal development was more commonly observed in fertilized eggs produced by broodstock in pre-puberty or senescence stages,which is probably related to the age of fish and the egg quality.This study can provide the materials for comparative analysis in toxicological and molecular studies of O.melastigma,and may provide evidence for other economic fish that produce sticky eggs.展开更多
To investigate the effect of reduced salinity on diatoms’ capacity to cope with changing ultraviolet radiation(U VR) and photosynthetically active radiation(PAR),Skeletonema costatum was grown in a range of salinity(...To investigate the effect of reduced salinity on diatoms’ capacity to cope with changing ultraviolet radiation(U VR) and photosynthetically active radiation(PAR),Skeletonema costatum was grown in a range of salinity(15,25,and 35).The photo system Ⅱ(PSⅡ) function was analyzed by increasing PAR and UVR to mimic a mixing event in turbulent waters.The re sults show that high UVR exposure significantly reduced PSII activity,especially in cells grown at low salinity.UVR,but not salinity,stimulated the ’removal’ rate of PSII protein PsbA.Salinity alone,in the range of 15 to 35,did not regulate PSⅡ acceptor region;however,the low salinity+UVR treatment decreased the energy flux for electron transport per PSⅡ reaction center in S.costatum.It showed that low salinity exacerbated the damaging effect of UVR on PSⅡ function in S.costatum by suppressing Psb A protein synthe sis and modifying the photochemistry of PSⅡ.Although higher catalase(CAT) activity and NPQs were induced,they were unable to prevent the combined damage effect of low salinity+UVR.Our findings indicate that reduced salinity and increased UVR potentially affect the abundance and distribution of S.costatum with the escalation of climate disturbances.展开更多
基金Supported by the National Key R&D Program of China(No.2018YFC1406406)the Science and Technology Program of Yantai(Nos.2018SFBF084,2019ZDCX018)。
文摘Fish embryos are widely used as models in toxicology,drug development,and human disease research because of their high sensitivity,observability,and operability,providing the basis for an in-depth understanding of the embryogenesis.Increasing studies have indicated that birth defects are hereditary.In this study,we used Oryzias melastigma as a model to conduct a study of 185-day embryogenesis and observed self-induced non-pathological abnormal embryogenesis.O.melastigma experienced pre-puberty stage,adolescence stage,and senescence stage,and individuals produced up to 102 eggs per day.However,the fecundity was markedly reduced during the senescent stage.During the active egg and blastodisc stages,pseudo-fertilization and pseudo-blastocysts were observed.During cleavage at the 4-to 32-cell stages,we observed blastomeres separation or dislocation.Excessively separated blastomeres formed double blastoderms,eventually resulting in conjoined twins.During the blastula stage,we observed abnormally increased cell volume,narrowed and elongated blastocysts,and abnormally coated blastoderms.At the organogenesis stage,we observed abnormal numbers of Kupff er’s vesicles and conjoined twins.Abnormality in the location and number of oil droplets were observed in various development stages.Abnormal development was more commonly observed in fertilized eggs produced by broodstock in pre-puberty or senescence stages,which is probably related to the age of fish and the egg quality.This study can provide the materials for comparative analysis in toxicological and molecular studies of O.melastigma,and may provide evidence for other economic fish that produce sticky eggs.
基金Supported by the Shandong Provincial Natural Science Foundation(Nos.ZR2019MC015,ZR2020QC025,ZR2020MD092)the open project of Rongcheng Marine Industrial Technology Research Institute,Ludong University(No.KF20180001)the Key Technology Research and Development Program of Shandong(No.2019GSF107091)。
文摘To investigate the effect of reduced salinity on diatoms’ capacity to cope with changing ultraviolet radiation(U VR) and photosynthetically active radiation(PAR),Skeletonema costatum was grown in a range of salinity(15,25,and 35).The photo system Ⅱ(PSⅡ) function was analyzed by increasing PAR and UVR to mimic a mixing event in turbulent waters.The re sults show that high UVR exposure significantly reduced PSII activity,especially in cells grown at low salinity.UVR,but not salinity,stimulated the ’removal’ rate of PSII protein PsbA.Salinity alone,in the range of 15 to 35,did not regulate PSⅡ acceptor region;however,the low salinity+UVR treatment decreased the energy flux for electron transport per PSⅡ reaction center in S.costatum.It showed that low salinity exacerbated the damaging effect of UVR on PSⅡ function in S.costatum by suppressing Psb A protein synthe sis and modifying the photochemistry of PSⅡ.Although higher catalase(CAT) activity and NPQs were induced,they were unable to prevent the combined damage effect of low salinity+UVR.Our findings indicate that reduced salinity and increased UVR potentially affect the abundance and distribution of S.costatum with the escalation of climate disturbances.
