Hybridization is widely used. However, for a long time, systematic theories and technologies related to hybridization in fish have been lacking. In this study, through long-term systematic research, we investigated an...Hybridization is widely used. However, for a long time, systematic theories and technologies related to hybridization in fish have been lacking. In this study, through long-term systematic research, we investigated and obtained the main rules regarding inheritance and reproduction related to fish distant hybridization. Furthermore, we established one-step and multistep breeding technologies that were suitable for interspecific hybridization and intraspecific hybridization. Simultaneously, we used these two breeding technologies to produce a batch of diploid fish lineages and tetraploid fish lineages and improved fishes. In addition, we widely discuss the methods, technologies and results of hybridization breeding, referring to the domestic and foreign literature on fish hybridization. We hope that this paper will be beneficial for the research and application of fish hybrid breeding.展开更多
Hybridization can combine the genomes of different strains or species, which leads to changes of genotype and phenotype in the hybrids. In this study, we aimed to investigate the genetic variations of hybrids(WR-F1 an...Hybridization can combine the genomes of different strains or species, which leads to changes of genotype and phenotype in the hybrids. In this study, we aimed to investigate the genetic variations of hybrids(WR-F1 and WR-F2) derived from the intraspecific hybridization of white crucian carp(Carassius auratus cuvieri, WCC, ♀) and red crucian carp(Carassius auratus red var., RCC, ♂). Here, we compared the orthologous genes in the liver transcriptomes of hybrids with those of WCC and RCC, and classified the orthologous genes into eight gene patterns within three categories(chimera, mutant, and biparental origin genes).The results revealed 19.04%, 4.17% chimeric genes and 6.90%, 5.05% mutations of orthologous genes in WR-F1 and WR-F2 respectively. Seventeen of twenty-three characterized genes(77%) were confirmed to be the chimeras at the genomic DNA level.The GO classification discovered that some chimeric and mutant genes were related to metabolic process, immune system and developmental process in WR-F1. Our results provide the new evidence that hybridization can combine the parental genomes,leading to changes in the genotype of the resultant hybrids. This is the first report on the formation of chimeric genes from fish intraspecific hybridization, which is potentially interesting from the context of both evolution and the genetic breeding of fish.展开更多
Distant hybridization refers to crosses between two different species, genera, or higher-ranking taxa, which can break species limits, increase genetic variation, and combine the biological characteristics of existing...Distant hybridization refers to crosses between two different species, genera, or higher-ranking taxa, which can break species limits, increase genetic variation, and combine the biological characteristics of existing species. It is an important way of creating genetic variation, fertile strains, and excellent characteristics in new strains and populations. Combining analyses and summaries from many inter-related documents in plants and animals, both domestic and international, including examples and long-standing research on distant hybridization in fish from our laboratory, we summarize and compare the similarities and differences in plant and animal distant hybridization. In addition, we analyze and review the biological characteristics of their different ploidy progenies and the possible causes of disparity in survival rates. Mechanisms of sterility in animal and plant distant hybrids are also discussed, and research methods for the study of biological characteristics of hybrids, including morphology, cytology,and molecular cytogenetics are presented. This paper aims to provide comprehensive research materials and to systematically compare the general and specific characteristics of plant and animal hybrids with regards to reproduction, genetics, growth traits,and other biological characteristics. It is hoped that this paper will have great theoretical and practical significance for the study of genetic breeding and biological evolution of plant and animal distant hybridization.展开更多
The white crucian carp(Carassius auratus cuvieri,WCC) not only is one of the most economically important fish in Asia,characterized by strong reproductive ability and rapid growth rates,but also represents a good germ...The white crucian carp(Carassius auratus cuvieri,WCC) not only is one of the most economically important fish in Asia,characterized by strong reproductive ability and rapid growth rates,but also represents a good germplasm to produce hybrid progenies with heterosis.Gene knockout technique provides a safe and acceptant way for fish breeding.Achieving gene knockout in WCC and its hybrid progeny will be of great importance for both genetic studies and hybridization breeding.Tyrosinase(TYR) is a key enzyme in melanin synthesis.Depletion of tyr in zebrafish and mice results in mosaic pigmentation or total albinism.Here,we successfully used CRISPR-Cas9 to target tyr in WCC and its hybrid progeny(WR) derived from the cross of WCC(♀) and red crucian carp(Carassius auratus red var.,RCC,♂).The level of TYR protein was significantly reduced in mutant WCC.Both the mutant WCC and the mutant WR showed different degrees of melanin reduction compared with the wild-type sibling control fish,resulting from different mutation efficiency ranging from 60% to 90%.In addition,the transcriptional expression profiles of a series of pivotal pigment synthesis genes,i.e.tyrp1,mitfa,mitfb,dct and sox10,were down-regulated in tyr-CRISPR WCC,which ultimately caused a reduction in melanin synthesis.These results demonstrated that tyr plays a key role in melanin synthesis in WCC and WR,and CRISPR-Cas9 is an effective tool for modifying the genome of economical fish.Furthermore,the tyr-CRISPR models could be valuable in understanding fundamental mechanisms of pigment formation in non-model fish.展开更多
Focusing on adaptation of aquatic organisms, especially fish, can help elucidate complex dynamics in freshwater ecology. The differences in genetic and epigenetic regulation between diploid and triploid Carassius aura...Focusing on adaptation of aquatic organisms, especially fish, can help elucidate complex dynamics in freshwater ecology. The differences in genetic and epigenetic regulation between diploid and triploid Carassius auratus affect survival under eutrophication. To identify the underlying mechanisms that lead to better adaption of triploids than diploids, we compared mRNA and microRNA(miRNA) expressions in liver tissue of diploid and triploid individuals obtained from the Dongting lake water system in central China. Differential expression analysis revealed that 566 transcripts were significantly up-regulated, whereas758 were down-regulated in triploids; of these differentially expressed transcripts, 33 transcripts including cacna1 d, nfkb2, hspa1 and fgfr4 were involved in the MAPK signaling pathway, and eight transcripts were determined to be regulated by seven miRNAs. Additionally, four of 25 differential expressed(DE) transcripts(mhc1, irf7, nfkb2 and pik3 c) involving the viral carcinogenesis pathway were regulated by four miRNAs. Furthermore, genetic polymorphisms analysis showed that more heterozygous mutations were detected in triploids than diploids. The d N/d S results revealed that 21 genes were under positive selection(d N/d S>1) in C. auratus complex. We hypothesize that these changes related to genetic and epigenetic regulation may be caused by abiotic stresses, and facilitate adaptation to environmental changes.展开更多
In the Dongting water system, the Carassius auratus(Crucian carp) complex is characterized by the coexistence of diploid forms(2n=100, 2n CC) and polyploid forms. Chromosomal and karyotypic analyses have suggested tha...In the Dongting water system, the Carassius auratus(Crucian carp) complex is characterized by the coexistence of diploid forms(2n=100, 2n CC) and polyploid forms. Chromosomal and karyotypic analyses have suggested that the polyploid C. auratus has a triploid(3n=150, 3n CC) and a tetraploid origin(4n=200), respectively. However, there is a lack of direct genetic evidence to support this conclusion. In this paper, analysis of the 5S r DNA chromosomal locus revealed that the 3n CC is of triploid origin. Analysis of the species-specific chromosomal centromere locus revealed that 3n CC individuals possess three sets of C. auratus-derived chromosomes. Our results provide direct cytogenetic evidence suggesting that individuals with 150 chromosomes are of autotriploid origin within the C. auratus complex. It marks an important contribution to the study of polyploidization and the evolution of vertebrates.展开更多
基金supported by the National Natural Science Foundation of China (31730098, 31430088, and 31802287)the Earmarked Fund for China Agriculture Research System (CARS-45)+2 种基金the Key Research and Development Program of Hunan Province (2018NK2072)Hunan Provincial Natural Science and Technology Major Project (2017NK1031)the Cooperative Innovation Center of Engineering and New Products for Developmental Biology of Hunan Province (20134486)
文摘Hybridization is widely used. However, for a long time, systematic theories and technologies related to hybridization in fish have been lacking. In this study, through long-term systematic research, we investigated and obtained the main rules regarding inheritance and reproduction related to fish distant hybridization. Furthermore, we established one-step and multistep breeding technologies that were suitable for interspecific hybridization and intraspecific hybridization. Simultaneously, we used these two breeding technologies to produce a batch of diploid fish lineages and tetraploid fish lineages and improved fishes. In addition, we widely discuss the methods, technologies and results of hybridization breeding, referring to the domestic and foreign literature on fish hybridization. We hope that this paper will be beneficial for the research and application of fish hybrid breeding.
基金supported by National Natural Science Foundation of China (31210103918, 31430088, 91631305)the earmarked fund for China Agriculture Research System (CARS-45)+1 种基金the Cooperative Innovation Center of Engineering and New Products for Developmental Biology of Hunan Province (20134486)the Construction Project of Key Discipline of Hunan Province and China and Natural Science Foundation of Hunan Province (14JJ2062)
文摘Hybridization can combine the genomes of different strains or species, which leads to changes of genotype and phenotype in the hybrids. In this study, we aimed to investigate the genetic variations of hybrids(WR-F1 and WR-F2) derived from the intraspecific hybridization of white crucian carp(Carassius auratus cuvieri, WCC, ♀) and red crucian carp(Carassius auratus red var., RCC, ♂). Here, we compared the orthologous genes in the liver transcriptomes of hybrids with those of WCC and RCC, and classified the orthologous genes into eight gene patterns within three categories(chimera, mutant, and biparental origin genes).The results revealed 19.04%, 4.17% chimeric genes and 6.90%, 5.05% mutations of orthologous genes in WR-F1 and WR-F2 respectively. Seventeen of twenty-three characterized genes(77%) were confirmed to be the chimeras at the genomic DNA level.The GO classification discovered that some chimeric and mutant genes were related to metabolic process, immune system and developmental process in WR-F1. Our results provide the new evidence that hybridization can combine the parental genomes,leading to changes in the genotype of the resultant hybrids. This is the first report on the formation of chimeric genes from fish intraspecific hybridization, which is potentially interesting from the context of both evolution and the genetic breeding of fish.
基金supported by National Natural Science Foundation of China(31430088,31210103918,91331105)National High Technology Research and Development Program of China(2011AA100403)+3 种基金the Cooperative Innovation Center of Engineering and New Products for Developmental Biology of Hunan Province(20134486)Project supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China(20114306130001)Educational Commission of Hunan Province(14B115)National Key Disciplines of Developmental Biology and Key Discipline Construction Project Funding for Developmental Biology of Hunan Province
文摘Distant hybridization refers to crosses between two different species, genera, or higher-ranking taxa, which can break species limits, increase genetic variation, and combine the biological characteristics of existing species. It is an important way of creating genetic variation, fertile strains, and excellent characteristics in new strains and populations. Combining analyses and summaries from many inter-related documents in plants and animals, both domestic and international, including examples and long-standing research on distant hybridization in fish from our laboratory, we summarize and compare the similarities and differences in plant and animal distant hybridization. In addition, we analyze and review the biological characteristics of their different ploidy progenies and the possible causes of disparity in survival rates. Mechanisms of sterility in animal and plant distant hybrids are also discussed, and research methods for the study of biological characteristics of hybrids, including morphology, cytology,and molecular cytogenetics are presented. This paper aims to provide comprehensive research materials and to systematically compare the general and specific characteristics of plant and animal hybrids with regards to reproduction, genetics, growth traits,and other biological characteristics. It is hoped that this paper will have great theoretical and practical significance for the study of genetic breeding and biological evolution of plant and animal distant hybridization.
基金supported by the National Natural Science Foundation of China (31430088, 31730098)the earmarked fund for China Agriculture Research System (CARS-45)+2 种基金the Cooperative Innovation Center of Engineering and New Products for Developmental Biology of Hunan Province (20134486)the Natural Science Foundation of Hunan Province (14JJ2062)the Research Foundation of Education Bureau of Hunan Province, China (16B160)
文摘The white crucian carp(Carassius auratus cuvieri,WCC) not only is one of the most economically important fish in Asia,characterized by strong reproductive ability and rapid growth rates,but also represents a good germplasm to produce hybrid progenies with heterosis.Gene knockout technique provides a safe and acceptant way for fish breeding.Achieving gene knockout in WCC and its hybrid progeny will be of great importance for both genetic studies and hybridization breeding.Tyrosinase(TYR) is a key enzyme in melanin synthesis.Depletion of tyr in zebrafish and mice results in mosaic pigmentation or total albinism.Here,we successfully used CRISPR-Cas9 to target tyr in WCC and its hybrid progeny(WR) derived from the cross of WCC(♀) and red crucian carp(Carassius auratus red var.,RCC,♂).The level of TYR protein was significantly reduced in mutant WCC.Both the mutant WCC and the mutant WR showed different degrees of melanin reduction compared with the wild-type sibling control fish,resulting from different mutation efficiency ranging from 60% to 90%.In addition,the transcriptional expression profiles of a series of pivotal pigment synthesis genes,i.e.tyrp1,mitfa,mitfb,dct and sox10,were down-regulated in tyr-CRISPR WCC,which ultimately caused a reduction in melanin synthesis.These results demonstrated that tyr plays a key role in melanin synthesis in WCC and WR,and CRISPR-Cas9 is an effective tool for modifying the genome of economical fish.Furthermore,the tyr-CRISPR models could be valuable in understanding fundamental mechanisms of pigment formation in non-model fish.
基金supported by the National Natural Science Foundation of China (317023343, 1430088, 31730098)the earmarked fund for China Agriculture Research System (CARS-45)+5 种基金the Key Research and Development Project of Hunan Province (2016NK2128)the Key Research and Development Project of Hunan Province (2016NK2128)Hunan Provincial Natural Science and Technology Major Project (2017NK1031)the Cooperative Innovation Center of Engineering and New Products for Developmental Biology of Hunan Province (20134486)the Construction Project of Key Discipline of Hunan Province and China, Natural Science Foundation of Hunan Province (14JJ2148)the Scientific Research Fund of Hunan Provincial Education Department (16C0974)
文摘Focusing on adaptation of aquatic organisms, especially fish, can help elucidate complex dynamics in freshwater ecology. The differences in genetic and epigenetic regulation between diploid and triploid Carassius auratus affect survival under eutrophication. To identify the underlying mechanisms that lead to better adaption of triploids than diploids, we compared mRNA and microRNA(miRNA) expressions in liver tissue of diploid and triploid individuals obtained from the Dongting lake water system in central China. Differential expression analysis revealed that 566 transcripts were significantly up-regulated, whereas758 were down-regulated in triploids; of these differentially expressed transcripts, 33 transcripts including cacna1 d, nfkb2, hspa1 and fgfr4 were involved in the MAPK signaling pathway, and eight transcripts were determined to be regulated by seven miRNAs. Additionally, four of 25 differential expressed(DE) transcripts(mhc1, irf7, nfkb2 and pik3 c) involving the viral carcinogenesis pathway were regulated by four miRNAs. Furthermore, genetic polymorphisms analysis showed that more heterozygous mutations were detected in triploids than diploids. The d N/d S results revealed that 21 genes were under positive selection(d N/d S>1) in C. auratus complex. We hypothesize that these changes related to genetic and epigenetic regulation may be caused by abiotic stresses, and facilitate adaptation to environmental changes.
基金supported by the National Natural Science Foundation of China (31201987, 31430088, 31210103918)the Doctoral Fund of Ministry of Education of China (20124306120006)+4 种基金the Natural Science Foundation of Hunan Province (14JJ6008)Training Program of the Major Research Plan of the National Natural Science Foundation of China (91331105)the National Key Basic Research Program of China (2012CB722305)the Cooperative Innovation Center of Engineering and New Products for Developmental Biology (20134486)the Construct Program of the Key Discipline in Hunan Province, China
文摘In the Dongting water system, the Carassius auratus(Crucian carp) complex is characterized by the coexistence of diploid forms(2n=100, 2n CC) and polyploid forms. Chromosomal and karyotypic analyses have suggested that the polyploid C. auratus has a triploid(3n=150, 3n CC) and a tetraploid origin(4n=200), respectively. However, there is a lack of direct genetic evidence to support this conclusion. In this paper, analysis of the 5S r DNA chromosomal locus revealed that the 3n CC is of triploid origin. Analysis of the species-specific chromosomal centromere locus revealed that 3n CC individuals possess three sets of C. auratus-derived chromosomes. Our results provide direct cytogenetic evidence suggesting that individuals with 150 chromosomes are of autotriploid origin within the C. auratus complex. It marks an important contribution to the study of polyploidization and the evolution of vertebrates.