In this study, we conducted a cross of white crucian carp （♀）xred crucian carp （♂） （WR）, and characterized the morphology, reproduction and genetics of the progeny. Different from parents, WR with the gray col...In this study, we conducted a cross of white crucian carp （♀）xred crucian carp （♂） （WR）, and characterized the morphology, reproduction and genetics of the progeny. Different from parents, WR with the gray color showed the hybrid morphological traits of both parents. WR possessed normal gonads producing mature eggs or sperm, and exhibited high fertilization rate （90.2%） and high hatchery rate （80.5%）, which contributed to produce and enlarge the population. WR with the same DNA content as parents was a diploid fish with 100 chromosomes （2n=100）. Amplified ITS of 45S rDNA, in WR the sequences consisting of 884 bp bases of the entire ITS-1 region, 5.8 S region, and entire ITS-2 region. The sequences showed high similarity between WR and its parents and leaned towards male inheritance. In WR, NTS of 5S rDNA consisted of three length types with total 654 bp bases. From sequence analysis of NTS, WR shared 94.2% and 95.1% similarities with their female and male parent, respectively. Sequence analysis of ITS and NTS revealed that there existed recombination and variation in the hybrid progeny, which was the genetic base for adaptation and speciation. In conclusion, we obtained WR from hybridization and it exhibited hybrid traits in morphology and variation in genetic composition showing essential difference with its parents. The obtainment of WR has important significance in fish genetic breeding.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
基金supported by Major International Cooperation Projects of the National Natural Science Foundation of China(31210103918)the National Natural Science Foundation of China(31201980,31430088 and 31272651)+5 种基金the National High Technology Research and Development Program of China(2011AA100403)the Natural Science Foundation of Hunan Province,China(14JJ3072)Science-Technology Foundation of Hunan Province,China(2014FJ3084)Research Foundation of Education Bureau of Hunan Province,China(13C523)the Cooperative Innovation Center of Engineering and New Products for Developmental Biology of Hunan Province(20134486)the Construct Program of the Key Discipline in Hunan Province,and Construct Program of the National Key Discipline
文摘In this study, we conducted a cross of white crucian carp （♀）xred crucian carp （♂） （WR）, and characterized the morphology, reproduction and genetics of the progeny. Different from parents, WR with the gray color showed the hybrid morphological traits of both parents. WR possessed normal gonads producing mature eggs or sperm, and exhibited high fertilization rate （90.2%） and high hatchery rate （80.5%）, which contributed to produce and enlarge the population. WR with the same DNA content as parents was a diploid fish with 100 chromosomes （2n=100）. Amplified ITS of 45S rDNA, in WR the sequences consisting of 884 bp bases of the entire ITS-1 region, 5.8 S region, and entire ITS-2 region. The sequences showed high similarity between WR and its parents and leaned towards male inheritance. In WR, NTS of 5S rDNA consisted of three length types with total 654 bp bases. From sequence analysis of NTS, WR shared 94.2% and 95.1% similarities with their female and male parent, respectively. Sequence analysis of ITS and NTS revealed that there existed recombination and variation in the hybrid progeny, which was the genetic base for adaptation and speciation. In conclusion, we obtained WR from hybridization and it exhibited hybrid traits in morphology and variation in genetic composition showing essential difference with its parents. The obtainment of WR has important significance in fish genetic breeding.
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.
