Recently,cilia defects have been proposed to contribute to scoliosis.Here,we demonstrate that coiled-coil domain-containing 57(Ccdc57)plays an essential role in straightening the body axis of zebrafish by regulating c...Recently,cilia defects have been proposed to contribute to scoliosis.Here,we demonstrate that coiled-coil domain-containing 57(Ccdc57)plays an essential role in straightening the body axis of zebrafish by regulating ciliary beating in the brain ventricle(BV).Zygotic ccdc57(Zccdc57)mutant zebrafish developes scoliosis without significant changes in their bone density and calcification,and the maternal-zygotic ccdc57(MZccdc57)mutant embryos display curved bodies since the long-pec stage.The expression of ccdc57 is enriched in ciliated tissues and immunofluorescence analysis reveals colocalization of Ccdc57-HA with acetylated a-tubulin,implicating it in having a role in ciliary function.Further examination reveals that it is the coordinated cilia beating of multiple cilia bundles(MCB)in the MZccdc57 mutant embryos that is affected at 48 hours post fertilization,when the compromised cerebrospinal fluid flow and curved body axis have already occurred.Either ccdc57 m RNA injection or epinephrine treatment reverses the spinal curvature in MZccdc57 mutant larvae from ventrally curly to straight or even dorsally curly and significantly upregulates urotensin signaling.This study reveals the role of ccdc57 in maintaining coordinated cilia beating of MCB in the BV.展开更多
Meiosis is the key process for producing mature gametes. A natural fertile triploid Carassius auratus population(3nDTCC) and an artificially derived sterile triploid crucian carp(3nCC) have been previously observed, p...Meiosis is the key process for producing mature gametes. A natural fertile triploid Carassius auratus population(3nDTCC) and an artificially derived sterile triploid crucian carp(3nCC) have been previously observed, providing suitable model organisms for investigating meiosis characteristics in triploid fish. In the present study, the microstructures and ultrastructures of spermatogenesis were studied in these fishes. Td T-mediated d UTP nick end labeling detection was performed to investigate the apoptosis of spermatocytes. Fluorescence in situ hybridization was employed to trace chromatin pairing. In addition, the m RNA expressions of cell cycle-related genes(i.e., cell division control 2 and cell cycle protein B) were determined by quantitative realtime polymerase chain reaction to illustrate the molecular mechanism of abnormal meiosis in the 3nCC. The results showed that the 3nCC undergoes an irregular prophase I, with the chromosomes distributed in a unipolar radial manner and exhibiting partial pairing, hindered metaphase I, and degenerated cells in the subsequent stages. Meanwhile, the 3nDTCC presented a relatively regular meiotic prophase I with complete conjugate chromosome pairs and chromosomes distributed along the karyotheca,which were presented as a ring structure by slicing. Only the spreads with 130–150 irregular chromosomes can be easily detected in the 3nDTCC, suggesting that it may undergo an abnormal metaphase I. This study provides new insights into the meiosis of fertile and sterile triploid cyprinid 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 terms of taxonomic status,common carp(Cyprinus carpio,Cyprininae)and crucian carp(Carassius auratus,Cyprininae)are different species;however,in this study,a newborn homodiploid crucian carp-like fish(2n=100)(2nNCRC...In terms of taxonomic status,common carp(Cyprinus carpio,Cyprininae)and crucian carp(Carassius auratus,Cyprininae)are different species;however,in this study,a newborn homodiploid crucian carp-like fish(2n=100)(2nNCRC)lineage(F1–F3)was established from the interspecific hybridization of female common carp(2n=100)×male blunt snout bream(Megalobrama amblycephala,Cultrinae,2n=48).The phenotypes and genotypes of 2 n NCRC differed from those of its parents but were closely related to those of the existing diploid crucian carp.We further sequenced the whole mitochondrial(mt)genomes of the 2n NCRC lineage from F1 to F3.The paternal mt DNA fragments were stably embedded in the mt-genomes of F1–F3 generations of 2n NCRC to form chimeric DNA fragments.Along with this chimeric process,numerous base sites of F1–F3 generations of 2 n NCRC underwent mutations.Most of these mutation sites were consistent with the existing diploid crucian carp.Moreover,the mt DNA organization and nucleotide composition of 2n NCRC were more similar to those of the existing diploid crucian carp than those of the parents.The inheritable chimeric DNA fragments and mutant loci in the mt-genomes of different generations of 2nNCRC provided important evidence of the mt DNA change process in the newborn lineage derived from hybridization of different species.Our findings demonstrated for the first time that the paternal mt DNA were transmitted into the mt-genomes of homodiploid lineage,which provided new insights into the existence of paternal mt DNA in the mt DNA inheritance.展开更多
基金supported by the National Key Research and Development Program,China(2018YFD0900406)the National Natural Science Foundation,China(31802291)the Natural Science Foundation of Hunan Province(2021JJ40342)。
文摘Recently,cilia defects have been proposed to contribute to scoliosis.Here,we demonstrate that coiled-coil domain-containing 57(Ccdc57)plays an essential role in straightening the body axis of zebrafish by regulating ciliary beating in the brain ventricle(BV).Zygotic ccdc57(Zccdc57)mutant zebrafish developes scoliosis without significant changes in their bone density and calcification,and the maternal-zygotic ccdc57(MZccdc57)mutant embryos display curved bodies since the long-pec stage.The expression of ccdc57 is enriched in ciliated tissues and immunofluorescence analysis reveals colocalization of Ccdc57-HA with acetylated a-tubulin,implicating it in having a role in ciliary function.Further examination reveals that it is the coordinated cilia beating of multiple cilia bundles(MCB)in the MZccdc57 mutant embryos that is affected at 48 hours post fertilization,when the compromised cerebrospinal fluid flow and curved body axis have already occurred.Either ccdc57 m RNA injection or epinephrine treatment reverses the spinal curvature in MZccdc57 mutant larvae from ventrally curly to straight or even dorsally curly and significantly upregulates urotensin signaling.This study reveals the role of ccdc57 in maintaining coordinated cilia beating of MCB in the BV.
基金This work was supported by the National Natural Science Foundation of China(31873038,31730098 and U19A2040)the earmarked fund for the China Agriculture Research System(CARS45)+1 种基金Key Research and Development Program of Hunan Province(2017NK1031)111 project(D20007).
文摘Meiosis is the key process for producing mature gametes. A natural fertile triploid Carassius auratus population(3nDTCC) and an artificially derived sterile triploid crucian carp(3nCC) have been previously observed, providing suitable model organisms for investigating meiosis characteristics in triploid fish. In the present study, the microstructures and ultrastructures of spermatogenesis were studied in these fishes. Td T-mediated d UTP nick end labeling detection was performed to investigate the apoptosis of spermatocytes. Fluorescence in situ hybridization was employed to trace chromatin pairing. In addition, the m RNA expressions of cell cycle-related genes(i.e., cell division control 2 and cell cycle protein B) were determined by quantitative realtime polymerase chain reaction to illustrate the molecular mechanism of abnormal meiosis in the 3nCC. The results showed that the 3nCC undergoes an irregular prophase I, with the chromosomes distributed in a unipolar radial manner and exhibiting partial pairing, hindered metaphase I, and degenerated cells in the subsequent stages. Meanwhile, the 3nDTCC presented a relatively regular meiotic prophase I with complete conjugate chromosome pairs and chromosomes distributed along the karyotheca,which were presented as a ring structure by slicing. Only the spreads with 130–150 irregular chromosomes can be easily detected in the 3nDTCC, suggesting that it may undergo an abnormal metaphase I. This study provides new insights into the meiosis of fertile and sterile triploid cyprinid 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(31802287,31730098,31430088)the China Postdoctoral Science Foundation(2018M632969)+3 种基金the earmarked fund for China Agriculture Research System(CARS-45)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In terms of taxonomic status,common carp(Cyprinus carpio,Cyprininae)and crucian carp(Carassius auratus,Cyprininae)are different species;however,in this study,a newborn homodiploid crucian carp-like fish(2n=100)(2nNCRC)lineage(F1–F3)was established from the interspecific hybridization of female common carp(2n=100)×male blunt snout bream(Megalobrama amblycephala,Cultrinae,2n=48).The phenotypes and genotypes of 2 n NCRC differed from those of its parents but were closely related to those of the existing diploid crucian carp.We further sequenced the whole mitochondrial(mt)genomes of the 2n NCRC lineage from F1 to F3.The paternal mt DNA fragments were stably embedded in the mt-genomes of F1–F3 generations of 2n NCRC to form chimeric DNA fragments.Along with this chimeric process,numerous base sites of F1–F3 generations of 2 n NCRC underwent mutations.Most of these mutation sites were consistent with the existing diploid crucian carp.Moreover,the mt DNA organization and nucleotide composition of 2n NCRC were more similar to those of the existing diploid crucian carp than those of the parents.The inheritable chimeric DNA fragments and mutant loci in the mt-genomes of different generations of 2nNCRC provided important evidence of the mt DNA change process in the newborn lineage derived from hybridization of different species.Our findings demonstrated for the first time that the paternal mt DNA were transmitted into the mt-genomes of homodiploid lineage,which provided new insights into the existence of paternal mt DNA in the mt DNA inheritance.
