Carnivorous fish have poor tolerance to carbohydrate in feed and low utilization rate of carbohydrate.Therefore,the balance of carbohydrate and lipids in the nutrient metabolism of carnivorous fish,the ef fective conv...Carnivorous fish have poor tolerance to carbohydrate in feed and low utilization rate of carbohydrate.Therefore,the balance of carbohydrate and lipids in the nutrient metabolism of carnivorous fish,the ef fective conversion and utilization of carbohydrate and lipids,and the feedback regulation of feeding are the key links for the e fficient utilization of carnivorous fish feed.Carbohydrate response element binding protein(ChREBP)is a new transcription factor found in recent years in the glucose signaling pathway,and can also participate in feeding regulation.We performed in-vivo and in-vitro experiments to reveal the role of ChREBP in the glucose metabolism and feeding in mandarin fish.The mRNA expression of ChREBP and appetite regulatory factors were measured after intraperitoneal injection of glucose in mandarin fish Siniperca chuatsi and cotransfection with glucose and glucose+siRNA in the hypothalamic cells in mandarin fish.The results reveal that at hour 2 and 4 post intraperitoneal injection with 1 mg/g BW glucose,the blood glucose level of the mandarin fish increased significantly,but food intake decreased significantly,and it also displayed a significantly increased ChREBP mRNA expression levels in liver.At hour 4 post injection,hypothalamic ChREBP mRNA level was significantly increased,whereas the mRNA expression levels of appetite genes neuropeptide Y(npy)and agouti-related peptide(AgRP)were decreased significantly.When the glucose concentration was 40 mmol/L,the expression level of ChREBP mRNA in mandarin fish hypothalamic cells was significantly up-regulated,but the expression level of appetite gene npy mRNA was down-regulated.When siRNA and glucose were co-transfected into mandarin fish brain cells,the expression level of chrebp mRNA was significantly decreased,and the appetite gene npy mRNA was significantly increased.The results indicated that glucose regulated food intake through the modulation of appetite gene npy by ChREBP.展开更多
肌球蛋白重链(Myosin heavy chain,MYH)是骨骼肌粗肌丝的重要组成单位,其表达量高低影响肌纤维的组成和肌肉生长。为了解其在翘嘴鳜(Siniperca chuatsi)早期生长过程中的作用,本研究从前期生长差异显著的2组(快长组和慢长组)翘嘴鳜幼鱼...肌球蛋白重链(Myosin heavy chain,MYH)是骨骼肌粗肌丝的重要组成单位,其表达量高低影响肌纤维的组成和肌肉生长。为了解其在翘嘴鳜(Siniperca chuatsi)早期生长过程中的作用,本研究从前期生长差异显著的2组(快长组和慢长组)翘嘴鳜幼鱼转录组差异表达Unigene中筛选出2个MYH基因,RACE(Rapid amplification of c DNA ends)克隆到其全长c DNA(MYH-7a,MYH-7b)。MYH-7a全长为6071 bp,开放阅读框为5820 bp;MYH-7b全长为5896 bp,开放阅读框为5745 bp。序列分析显示,2个MYH均有Loop1、Loop2环、ATP结合位点等关键结构域;进化树聚类分析显示,MYH-7a与MYH-7b均属于慢肌球蛋白。实时荧光定量PCR验证发现,其在快长组样本中表达量显著高于慢长组,与转录组测序结果一致;检测其在翘嘴鳜心肌、红白肌和皮肤等14种组织的表达水平,结果显示,MYH-7a主要在心肌中表达,而MYH-7b主要在红肌中表达;在胚胎发育不同阶段,二者随着胚胎发育的进行,表达量不断增加;在幼鱼早期生长过程(孵化出膜后15 dph、30 dph和60 dph)的翘嘴鳜白肌中,在15 dph和30 dph快长组的表达量显著高于慢长组,而到60 dph时快长组的表达量均显著低于慢长组。翘嘴鳜MYH-7a、MYH-7b在快长组与慢长组鱼中的差异表达提示它们在翘嘴鳜胚胎及其早期生长发育过程中发挥重要作用。展开更多
Serum immunoglobulin from the mandarin fish, or the so called Chinese perch, Siniperca chuatsi (Basilewsky), was successfully purified using affinity chromatography. Heavy and light chains were detected on electrophor...Serum immunoglobulin from the mandarin fish, or the so called Chinese perch, Siniperca chuatsi (Basilewsky), was successfully purified using affinity chromatography. Heavy and light chains were detected on electrophoresis gel, with molecular weights being estimated at 72 and 29 kDa, respectively. The tetrameric IgM of S. chuatsi was calculated to be 808 kDa. The rabbit polyclonal antisera against the purifed immunoglobulin were developed and tested by Western blot analysis. The antisera reacted strongly with the heavy chains of S. chuatsi immunoglobulin. Humoral immune responses of the mandarin fish can then be examined using the developed polyclonal antibody.展开更多
The purpose of this study was to evaluate the potential of a host-associated Bacillus subtilis 1-C-7 as a probiotic for Chinese perch(Siniperca chuatsi).Four test diets were formulated to contain graded levels of B.su...The purpose of this study was to evaluate the potential of a host-associated Bacillus subtilis 1-C-7 as a probiotic for Chinese perch(Siniperca chuatsi).Four test diets were formulated to contain graded levels of B.subtilis 1-C-7 at 0(CY),0.85×10^(8)(Y1),0.95×10^(9)(Y2)and 0.91×10^(10)(Y3)CFU/kg diet.The test fish with initial weight 30.0±1.2 g were fed the 4 test diets with 3 replicates in an indoor water-flow aquaculture system with 12 net cages(40 fish/cage)for 10 wk.At the conclusion of the feeding trial,the probiotic effects of B.subtilis on Chinese perch were analyzed based on growth performance,serum biochemical indices,histologic morphology of liver and gut,gut microbiota and the resistance to Aero-monas hydrophila.The results showed that the percentage of weight gain had no significant change in the Y1 and Y2 groups(P>0.05)but decreased in the Y3 group compared to that in the CY group(P<0.05).The fish in the Y3 group displayed the highest activity of serum alanine aminotransferase(ALT)and aspartate aminotransferase(AST)among these 4 groups(P<0.05).The fish in the CY group had the highest value of malondialdehyde in the liver(P<0.05)and showed severe nuclear migration and vacuolization of hepatocytes.The morphology indicated that all test fish had poor intestinal health.However,the fish in the Y1 group had a relatively normal intestinal histologic structure.The mid gut microbial diversity analysis showed that dietary B.subtilis supplementation increased the abundance of probiotics such as Tenericutes and Bacteroides,whereas it reduced the abundance of pernicious bacteria such as Proteobacteria,Actinobacteria,Thermophilia and Spirochaetes.The challenge test showed that dietary B.subtilis supplementation increased the resistance to A.hydrophila in Chinese perch.In conclusion,dietary supplementation of 0.85×10^(8)CFU/kg B.subtilis 1-C-7 could improve the intestinal microbiota,intestinal health and disease resistance in Chinese perch,but more or excessive supple-mentation could reduce growth performance and have negative effects on health.展开更多
Most of the closely related fish species are similar in appearance,with slight differences.This study evaluated 35 morphological characteristic parameters and the number,shape,and spatial location of bones in the skul...Most of the closely related fish species are similar in appearance,with slight differences.This study evaluated 35 morphological characteristic parameters and the number,shape,and spatial location of bones in the skull and vertebrae of the mandarin fish Siniperca chuatsi and big-eye mandarin fish Siniperca kneri.We can understand their ecological adaptability,compare their morphological and skeletal differences,and elucidate the relationship between their phenotypic trait differences and skeletal characteristics.The results were as follows:1.The Student’s t-test results revealed significant differences between S.chuatsi and S.kneri in terms of head depth,head back length,snout length,interorbital distance,distance of the eyes from the oral fissure,and width between the posterior trunk and base of the caudal fin.Principal component and discriminant analysis showed that the main morphological differences between S.chuatsi and S.kneri were in the eye position,head hump and body shape.2.There was no significant difference in the number and shape of the skull and vertebrae between S.chuatsi and S.kneri,but they differed in spatial position.The terminus of the maxilla in S.chuatsi is located at the lower border of the postorbital bone,but at the anterior in S.kneri.The size of head hump is closely related to the spatial location of the splanchnocranium in S.chuatsi and S.kneri.The angles between the caudal vertebrae centrum and each of the following:the neural arch and spine;haemal arch and spine of S.chuatsi are larger than those of S.kneri.In conclusion,the morphological differences between S.chuatsi and S.kneri are closely related to the spatial position of skeleton.These phenotypic differences reflect the ecological adaptation of mandarin fish to different natural environments.展开更多
Due to the difficulty in accurately identifying structural variants(SVs) across genomes,their impact on cisregulato ry diverge n ce of closely related species,especially fish,remains to be explored.Recently identified...Due to the difficulty in accurately identifying structural variants(SVs) across genomes,their impact on cisregulato ry diverge n ce of closely related species,especially fish,remains to be explored.Recently identified broad H3K4me3 domains are essential for the regulation of genes involved in several biological processes.However,the role of broad H3K4me3 domains in phenotypic divergence remains poorly understood.Siniperca chuatsi and S.scherzeri are closely related but divergent in several phenotypic traits,making them an ideal model to study cis-regulatory evolution in sister species.Here,we generated chromosome-level genomes of S.chuatsi and S.scherzeri,with assembled genome sizes of 716.35 and740.54 Mb,respectively.The evolutionary histories of S.chuatsi and S.scherzeri were studied by inferring dynamic changes in ancestral population sizes.To explore the genetic basis of adaptation in S.chuatsi and S.scherzeri,we performed gene family expansion and contraction analysis and identified positively selected genes(PSGs).To investigate the role of SVs in cis-regulatory divergence of closely related fish species,we identified high-quality SVs as well as divergent H3K27ac and H3K4me3 domains in the genomes of S.chuatsi and S.scherzeri.Integrated analysis revealed that cis-regulatory divergence caused by SVs played an essential role in phenotypic divergence between S.chuatsi and S.scherzeri.Additionally,divergent broad H3K4me3 domains were mostly associated with cancer-related genes in S.chuatsi and S.scherzeri and contributed to their phenotypic divergence.展开更多
基金Supported by the China Agriculture Research System (No.CARS-46)the National Key R&D Program of China (No.2018YFD0900400)。
文摘Carnivorous fish have poor tolerance to carbohydrate in feed and low utilization rate of carbohydrate.Therefore,the balance of carbohydrate and lipids in the nutrient metabolism of carnivorous fish,the ef fective conversion and utilization of carbohydrate and lipids,and the feedback regulation of feeding are the key links for the e fficient utilization of carnivorous fish feed.Carbohydrate response element binding protein(ChREBP)is a new transcription factor found in recent years in the glucose signaling pathway,and can also participate in feeding regulation.We performed in-vivo and in-vitro experiments to reveal the role of ChREBP in the glucose metabolism and feeding in mandarin fish.The mRNA expression of ChREBP and appetite regulatory factors were measured after intraperitoneal injection of glucose in mandarin fish Siniperca chuatsi and cotransfection with glucose and glucose+siRNA in the hypothalamic cells in mandarin fish.The results reveal that at hour 2 and 4 post intraperitoneal injection with 1 mg/g BW glucose,the blood glucose level of the mandarin fish increased significantly,but food intake decreased significantly,and it also displayed a significantly increased ChREBP mRNA expression levels in liver.At hour 4 post injection,hypothalamic ChREBP mRNA level was significantly increased,whereas the mRNA expression levels of appetite genes neuropeptide Y(npy)and agouti-related peptide(AgRP)were decreased significantly.When the glucose concentration was 40 mmol/L,the expression level of ChREBP mRNA in mandarin fish hypothalamic cells was significantly up-regulated,but the expression level of appetite gene npy mRNA was down-regulated.When siRNA and glucose were co-transfected into mandarin fish brain cells,the expression level of chrebp mRNA was significantly decreased,and the appetite gene npy mRNA was significantly increased.The results indicated that glucose regulated food intake through the modulation of appetite gene npy by ChREBP.
文摘肌球蛋白重链(Myosin heavy chain,MYH)是骨骼肌粗肌丝的重要组成单位,其表达量高低影响肌纤维的组成和肌肉生长。为了解其在翘嘴鳜(Siniperca chuatsi)早期生长过程中的作用,本研究从前期生长差异显著的2组(快长组和慢长组)翘嘴鳜幼鱼转录组差异表达Unigene中筛选出2个MYH基因,RACE(Rapid amplification of c DNA ends)克隆到其全长c DNA(MYH-7a,MYH-7b)。MYH-7a全长为6071 bp,开放阅读框为5820 bp;MYH-7b全长为5896 bp,开放阅读框为5745 bp。序列分析显示,2个MYH均有Loop1、Loop2环、ATP结合位点等关键结构域;进化树聚类分析显示,MYH-7a与MYH-7b均属于慢肌球蛋白。实时荧光定量PCR验证发现,其在快长组样本中表达量显著高于慢长组,与转录组测序结果一致;检测其在翘嘴鳜心肌、红白肌和皮肤等14种组织的表达水平,结果显示,MYH-7a主要在心肌中表达,而MYH-7b主要在红肌中表达;在胚胎发育不同阶段,二者随着胚胎发育的进行,表达量不断增加;在幼鱼早期生长过程(孵化出膜后15 dph、30 dph和60 dph)的翘嘴鳜白肌中,在15 dph和30 dph快长组的表达量显著高于慢长组,而到60 dph时快长组的表达量均显著低于慢长组。翘嘴鳜MYH-7a、MYH-7b在快长组与慢长组鱼中的差异表达提示它们在翘嘴鳜胚胎及其早期生长发育过程中发挥重要作用。
文摘Serum immunoglobulin from the mandarin fish, or the so called Chinese perch, Siniperca chuatsi (Basilewsky), was successfully purified using affinity chromatography. Heavy and light chains were detected on electrophoresis gel, with molecular weights being estimated at 72 and 29 kDa, respectively. The tetrameric IgM of S. chuatsi was calculated to be 808 kDa. The rabbit polyclonal antisera against the purifed immunoglobulin were developed and tested by Western blot analysis. The antisera reacted strongly with the heavy chains of S. chuatsi immunoglobulin. Humoral immune responses of the mandarin fish can then be examined using the developed polyclonal antibody.
基金supported by the Fund of Fujian Key Laboratory of Functional Aquafeed and Culture Environment Control(FACE20200004)and China Agriculture Research System(CARS-46).
文摘The purpose of this study was to evaluate the potential of a host-associated Bacillus subtilis 1-C-7 as a probiotic for Chinese perch(Siniperca chuatsi).Four test diets were formulated to contain graded levels of B.subtilis 1-C-7 at 0(CY),0.85×10^(8)(Y1),0.95×10^(9)(Y2)and 0.91×10^(10)(Y3)CFU/kg diet.The test fish with initial weight 30.0±1.2 g were fed the 4 test diets with 3 replicates in an indoor water-flow aquaculture system with 12 net cages(40 fish/cage)for 10 wk.At the conclusion of the feeding trial,the probiotic effects of B.subtilis on Chinese perch were analyzed based on growth performance,serum biochemical indices,histologic morphology of liver and gut,gut microbiota and the resistance to Aero-monas hydrophila.The results showed that the percentage of weight gain had no significant change in the Y1 and Y2 groups(P>0.05)but decreased in the Y3 group compared to that in the CY group(P<0.05).The fish in the Y3 group displayed the highest activity of serum alanine aminotransferase(ALT)and aspartate aminotransferase(AST)among these 4 groups(P<0.05).The fish in the CY group had the highest value of malondialdehyde in the liver(P<0.05)and showed severe nuclear migration and vacuolization of hepatocytes.The morphology indicated that all test fish had poor intestinal health.However,the fish in the Y1 group had a relatively normal intestinal histologic structure.The mid gut microbial diversity analysis showed that dietary B.subtilis supplementation increased the abundance of probiotics such as Tenericutes and Bacteroides,whereas it reduced the abundance of pernicious bacteria such as Proteobacteria,Actinobacteria,Thermophilia and Spirochaetes.The challenge test showed that dietary B.subtilis supplementation increased the resistance to A.hydrophila in Chinese perch.In conclusion,dietary supplementation of 0.85×10^(8)CFU/kg B.subtilis 1-C-7 could improve the intestinal microbiota,intestinal health and disease resistance in Chinese perch,but more or excessive supple-mentation could reduce growth performance and have negative effects on health.
基金This study was supported by China Agriculture Research System(CARS-46).
文摘Most of the closely related fish species are similar in appearance,with slight differences.This study evaluated 35 morphological characteristic parameters and the number,shape,and spatial location of bones in the skull and vertebrae of the mandarin fish Siniperca chuatsi and big-eye mandarin fish Siniperca kneri.We can understand their ecological adaptability,compare their morphological and skeletal differences,and elucidate the relationship between their phenotypic trait differences and skeletal characteristics.The results were as follows:1.The Student’s t-test results revealed significant differences between S.chuatsi and S.kneri in terms of head depth,head back length,snout length,interorbital distance,distance of the eyes from the oral fissure,and width between the posterior trunk and base of the caudal fin.Principal component and discriminant analysis showed that the main morphological differences between S.chuatsi and S.kneri were in the eye position,head hump and body shape.2.There was no significant difference in the number and shape of the skull and vertebrae between S.chuatsi and S.kneri,but they differed in spatial position.The terminus of the maxilla in S.chuatsi is located at the lower border of the postorbital bone,but at the anterior in S.kneri.The size of head hump is closely related to the spatial location of the splanchnocranium in S.chuatsi and S.kneri.The angles between the caudal vertebrae centrum and each of the following:the neural arch and spine;haemal arch and spine of S.chuatsi are larger than those of S.kneri.In conclusion,the morphological differences between S.chuatsi and S.kneri are closely related to the spatial position of skeleton.These phenotypic differences reflect the ecological adaptation of mandarin fish to different natural environments.
基金supported by the National Natural Science Foundation of China (31900309)Guangdong Basic and Applied Basic Research Foundation (2019A1515011644)+2 种基金Key-Area Research and Development Program of Guangdong Province (2021B0202020001)Seed Industry Development Project of Agricultural and Rural Department of Guangdong Province (2022)Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)(311021006)。
文摘Due to the difficulty in accurately identifying structural variants(SVs) across genomes,their impact on cisregulato ry diverge n ce of closely related species,especially fish,remains to be explored.Recently identified broad H3K4me3 domains are essential for the regulation of genes involved in several biological processes.However,the role of broad H3K4me3 domains in phenotypic divergence remains poorly understood.Siniperca chuatsi and S.scherzeri are closely related but divergent in several phenotypic traits,making them an ideal model to study cis-regulatory evolution in sister species.Here,we generated chromosome-level genomes of S.chuatsi and S.scherzeri,with assembled genome sizes of 716.35 and740.54 Mb,respectively.The evolutionary histories of S.chuatsi and S.scherzeri were studied by inferring dynamic changes in ancestral population sizes.To explore the genetic basis of adaptation in S.chuatsi and S.scherzeri,we performed gene family expansion and contraction analysis and identified positively selected genes(PSGs).To investigate the role of SVs in cis-regulatory divergence of closely related fish species,we identified high-quality SVs as well as divergent H3K27ac and H3K4me3 domains in the genomes of S.chuatsi and S.scherzeri.Integrated analysis revealed that cis-regulatory divergence caused by SVs played an essential role in phenotypic divergence between S.chuatsi and S.scherzeri.Additionally,divergent broad H3K4me3 domains were mostly associated with cancer-related genes in S.chuatsi and S.scherzeri and contributed to their phenotypic divergence.
