The Mest （mesoderm-specific transcript） gene has been considered an imprinting gene in human and mouse, and was also confirmed in other mammals and flowering plants. To investigate the function and evolution of this...The Mest （mesoderm-specific transcript） gene has been considered an imprinting gene in human and mouse, and was also confirmed in other mammals and flowering plants. To investigate the function and evolution of this gene, the cDNA of full length Mest gene was obtained using 5＇- and 3＇-RACE from the Chinese Large Toad （Bufo gargarizans）. The transcript is 1 325bp in length which contains a complete open reading frame （ORF） encoding a polypeptide of 326 amino acids （GenBank accession number： ABQ10905）. There is a typical 0./13 hydrolase fold domain in the putative gene product, and it shows high similarity to sequence of homologous protein of Xenopus tropicali （86%）, mammlian （70% - 80%）. RT-PCR （reverse transcriptase-polymerase chain reaction） analysis demonstrated that the Bufo gargarizans Mest （BgMest） gene is expressed widely in testis, ovary, liver, kidney, spleen, brain, stomach and lung. The conservation of the BgMest gene sequences, protein secondary structure of the BgMest protein, in addition to the expression pattern of the BgMest gene, suggested that the function of BgMest was conserved in amphibians. However, the phylogenetic tree of the imprinting gene of the mammals and other vertebrates examined in this study indicated their divergent origins.展开更多
Objective] The aim of this study was to investigate the electrophysiological characteristics of spontaneous electrical activities of olfactory bulb in Bufo gargarizans during postembryonic development. [Method] Microe...Objective] The aim of this study was to investigate the electrophysiological characteristics of spontaneous electrical activities of olfactory bulb in Bufo gargarizans during postembryonic development. [Method] Microelectrode technique was used to record extracellular spontaneous electrical activities of olfactory bulb in B. gar-garizans. [Result] Along with the development of olfactory bulb, the discharge types increased gradual y. Single spontaneous firing enhanced gradual y and it reached the maximum in the metamorphosis phase. The intensity of consecutive single sponta-neous firing changed slightly at the middle of post-embryonic development, but it was stil higher than in the early phase and the adult phase. Consecutive burst spontaneous firing frequency went down over time. [Conclusion] Along with the de-velopment of olfactory bulb, the neuronal excitability increases step by step and the neuronal electrical activities diversify gradualy.展开更多
[Objective] The aim was to probe into developing changes of spontaneous electrical activities of primordial hippocampus in Bufo bufo gargarizans in postembryonic phase. [Method] Microelectrode technique was used to re...[Objective] The aim was to probe into developing changes of spontaneous electrical activities of primordial hippocampus in Bufo bufo gargarizans in postembryonic phase. [Method] Microelectrode technique was used to record extracellularly spontaneous electrical activities of neurons in primordial hippocampus of B.bufo gargarizans in postembryonic phase. [Result] Single, consecutive single, burst, consecutive burst and anomalous spontaneous firing were recorded in primordial hippocampus, in which four kinds of spontaneous firings were recorded in forepart of postembryonic development except the anomalous spontaneous firing, and the burst spontaneous firing and consecutive burst spontaneous firing were predominant. The five kinds of spontaneous firings mentioned were recorded in anaphase of postembryonic development and the single and burst spontaneous firing were predominant.Following with the development of primordial hippocampus, the amplitudes of action potential of single firing and consecutive firing enhanced gradually, and it reaches the maximum in the metamorphosis phase; the differences of the frequencies of consecutive single firing and consecutive burst firing were not significant. [Conclusion] Following with the development of primordial hippocampus, the neuronal electrical activities showed diversification, the developmental degree of the primordial hippocampus in the metamorphosis phase was close to the subadult and adult.展开更多
Microelectrode technique was used to record the spontaneous electrical activities of the neurons in olfactory bulb of the Bufo bufo gargarizans, both in hibernation and after hibemation. This study investigated the el...Microelectrode technique was used to record the spontaneous electrical activities of the neurons in olfactory bulb of the Bufo bufo gargarizans, both in hibernation and after hibemation. This study investigated the electrophysiological characteristics of amphibian olfactory bulb in the period of hibernation and after hibernation and its effects on the start of hibernation and spontaneous awakening. The research showed four forms of spontaneous firings： single spontaneous firing, burst spontaneous firing, irregular spontaneous firing and consecutive single spontaneous firing. The single spontaneous firing includes slow depolarized spontaneous firing and fast depolarized spontaneous firing, and the slow depolarized spontaneous firing occurs only during the hibernation period. In hibernation, the low amplitude and low frequency firing with a longer duration may be relevant to maintaining the tonicity of the central nervous system in toads that are in hibernation, and this kind of firing may also provide an excited basis for their arousal from hibernation. After hibernation, the amplitude and frequency of firing increase, but the firing duration gets shorter. This form of short-term firing, which may be a phenomenon of sensory neurons fast adapting, is one of the neuronal mechanisms for the arousal of hibernating animals.展开更多
Three new C-3 dehydrated bufadienolides were isolated from the venom of Bufo bufo gargarizans. Their structures were elucidated as 5β,12β-12,14-dihydroxy-11-oxobufa-3,20,22-trienolide （1）, 5β,12β- 12,14-dihydrox...Three new C-3 dehydrated bufadienolides were isolated from the venom of Bufo bufo gargarizans. Their structures were elucidated as 5β,12β-12,14-dihydroxy-11-oxobufa-3,20,22-trienolide （1）, 5β,12β- 12,14-dihydroxy-11 -oxobufa-2,20,22-trienolide （2）, and 5β,12β-12,14-dihydroxy-11 -oxobufa-2,20,22- trienolide （3） on the basis of extensive spectroscopic analysis, especially 1D NMR and 2D NMR data. In addition, all three compounds were tested for their cytotoxic activities against A549 and HepG2 cancer cell lines. Compounds 2 and 3 showed significant cytotoxicities with IC50 values less than 10 μmol/L on both cancer cells.展开更多
In many anurans, the forelimb muscles of males are used to grasp females and are often heavier than those of females despite the larger female body size. Such sexual dimorphism in forelimb musculature is thought to re...In many anurans, the forelimb muscles of males are used to grasp females and are often heavier than those of females despite the larger female body size. Such sexual dimorphism in forelimb musculature is thought to result from sexual selection. In addition, the hindlimbs of frogs and toads play an important role in the reproductive process as amplectant males can expel rivals with robust hindlimbs through kicking. In this study, the sexual dimorphism in dry mass for six hindlimb muscles of the Asiatic toad （Bufo gargarizans） was investigated. The results showed that, when controlled for body size, the hindlimb muscle mass of males significantly exceeded that of females for every muscle. The hindlimb muscle mass of amplectant males was also significantly larger than that of non-amplectant males. These results suggested that if strong hindlimb muscles could improve mating success of males, sexual selection would promote the evolution of dimorphism in this character.展开更多
Two new bufotoxins,tolocinobufagin-3-succinoylarginine ester and tolocinobufagin-3-hemisuberate, were isolated from the skin of Bufo bufo gargarizans Cantor.Cinobufagin-3-hemisuberate was also isolated from the natura...Two new bufotoxins,tolocinobufagin-3-succinoylarginine ester and tolocinobufagin-3-hemisuberate, were isolated from the skin of Bufo bufo gargarizans Cantor.Cinobufagin-3-hemisuberate was also isolated from the natural source for the first time.Their structures were established using spectroscopic methods.展开更多
Three anti-keratin MAbs were used to identifykeratins expressed in early embryos of Bufo bufogargarizans.MAb AF5 recognized three polypeptides ofkeratin in oocytes,fertilized eggs,up to neurula withMr of 68,65 and 60K...Three anti-keratin MAbs were used to identifykeratins expressed in early embryos of Bufo bufogargarizans.MAb AF5 recognized three polypeptides ofkeratin in oocytes,fertilized eggs,up to neurula withMr of 68,65 and 60Kd respectively.At tailbud stage,three other keratins(62,58 and 54Kd)began to expressand could be detected by AF5.MAbs D10 and K12 gavedifferent results,both of them could identify four keratin-like molecules with unusual molecular weights(Mr 98,95,30 and 27 Kd).Moreover,D10 could also detect a 54 Kdkeratin in neurula and tailbud stage embryos,while K12could reveal,beside 54Kd keratin,other four more kera-tins(68,65,62 and 60 Kd).The possible interpretation ofthese results and their implications are discussed.展开更多
The taxonomic status of Bufo species in East Asia,particularly those closely related to B.gargarizans,has been controversial for over half a century,and recent molecular studies further fueled the dispute.Whether B.an...The taxonomic status of Bufo species in East Asia,particularly those closely related to B.gargarizans,has been controversial for over half a century,and recent molecular studies further fueled the dispute.Whether B.andrewsi,B.bankorensis,B.minshanicus,B.sachalinensis,B.tibetanus,and B.tuberculatus constitute valid species or are geographic or ecological variants of B.gargarizans is at the centre of the discussion.Most of these forms possess morphological diagnostic traits,but those differences are minimal and often inconsistent.Molecular data produced many contradictory patterns.Lack of clear diagnostic characters,different usage or definition of various names,mis-identified specimens,limited amount of data or samples,and frequent inter-specific hybridization may all have contributed to the current controversies.Some contradiction may also result from differences between similarity-based clustering and gene tree-based branching patterns.Nevertheless,a dominant allopatric differentiation pattern within this species complex is apparent,and several regional population groups have been identified.Some of the groups resemble old names(e.g.B.minshanicus,B.tibetanus),while others are new.These groups may represent geographic or ecological variants,incipient species,or valid species,and the current data do not warrant a convincing taxonomic revision.To move forward,a single study with comprehensive sampling and genomic data is needed to establish a solid framework,which will define naturally existing population clusters/lineages,and detect their levels of divergence and approximate geographic boundaries.Morphological and ecological examination will follow to understand their biology,determine their taxonomic status,and identify consistent diagnostic characters if necessary.展开更多
Relatively little is known about the relationship between Bufo gargarizans populations from Zhoushan Archipelago and nearby continental regions on the Pacific coast of eastern China.In this paper,155 new specimens of ...Relatively little is known about the relationship between Bufo gargarizans populations from Zhoushan Archipelago and nearby continental regions on the Pacific coast of eastern China.In this paper,155 new specimens of B.gargarizans from Zhoushan Archipelago and adjacent continents and 71 published specimens of B.gargarizans from China's Mainland were studied.Phylogeographical and dating analyses of B.gargarizans were performed using mitochondrial DNA sequencing with a length of 1436 bp.A mt DNA tree that indicated seven major clades was obtained.The earliest split in the mt DNA tree corresponding to the divergence of populations from the western highland region occurred approximately 4.0 million years ago（mya）.A subsequent clade occurred about 3.4 mya,with cladogenesis continuing toward the end of the Pleistocene.The continental clades were distributed in the western,central and northeastern regions of China.Zhoushan Archipelago clades consisted of two largely geographically overlapping subclades with the mt DNA divergence time of 0.73 mya.These results indicated there was extensive dispersal after vicariance.The B.gargarizans populations on Zhoushan Archipelago most probably originated from populations in nearby eastern continental regions of China.It was concluded that geological uplifting during the Pliocene and several sea-level changes in Pleistocene might have influenced the divergence and population demographical history of this species.展开更多
【目的】探究无尾两栖类变态前后身体大小、应激反应和免疫功能与特定生活史阶段的关系。【方法】以中华蟾蜍(Bufo gargarizans)为研究对象,测定其从33~35期蝌蚪发育至46期幼蟾过程中的体质量、体全长、各型白细胞的百分比、嗜中性粒细...【目的】探究无尾两栖类变态前后身体大小、应激反应和免疫功能与特定生活史阶段的关系。【方法】以中华蟾蜍(Bufo gargarizans)为研究对象,测定其从33~35期蝌蚪发育至46期幼蟾过程中的体质量、体全长、各型白细胞的百分比、嗜中性粒细胞与淋巴细胞的比值(ratio of neutrophils to lymphocytes,N/L),以及植物血凝素(phytohemagglutinin,PHA-P)反应的变化。【结果】(1)中华蟾蜍的体质量和体全长均在38~39期最高,46期最低(P<0.05);体质量与体全长的比值46期最高,41~42期最低(P<0.05)。(2)PHA-P最大反应值均出现于注射后3 h,其中33~35期、37期和38~39期的反应值均显著高于41~42期和46期(P<0.05)。(3)单核细胞、淋巴细胞和嗜碱性粒细胞的百分比在不同发育阶段无显著变化(P>0.05);嗜中性粒细胞的百分比37期最高,33~35期其次,均显著高于38~39期(P<0.05);嗜酸性粒细胞的百分比46期最高,37期和38~39期其次,均显著高于41~42期(P<0.05)。N/L在37期最高,33~35期其次,均显著高于38~39期(P<0.05)。【结论】中华蟾蜍从水生向陆生生活过渡过程中,应激反应能力在变态前期最高,临近变态期最低,免疫系统不同组分被激活或受抑制的时间段不同,这些生理特征的“错配”可能是其登陆成功率低的主要原因之一。展开更多
基金Supported by the National Natural Science Foundation of China (No.30770296)the Natural and Science Key Project of Anhui Educational Department (KJ2007A022)the Key Lab Project of Biotic Environment and Ecology Safety in Anhui Province (2006)
文摘The Mest （mesoderm-specific transcript） gene has been considered an imprinting gene in human and mouse, and was also confirmed in other mammals and flowering plants. To investigate the function and evolution of this gene, the cDNA of full length Mest gene was obtained using 5＇- and 3＇-RACE from the Chinese Large Toad （Bufo gargarizans）. The transcript is 1 325bp in length which contains a complete open reading frame （ORF） encoding a polypeptide of 326 amino acids （GenBank accession number： ABQ10905）. There is a typical 0./13 hydrolase fold domain in the putative gene product, and it shows high similarity to sequence of homologous protein of Xenopus tropicali （86%）, mammlian （70% - 80%）. RT-PCR （reverse transcriptase-polymerase chain reaction） analysis demonstrated that the Bufo gargarizans Mest （BgMest） gene is expressed widely in testis, ovary, liver, kidney, spleen, brain, stomach and lung. The conservation of the BgMest gene sequences, protein secondary structure of the BgMest protein, in addition to the expression pattern of the BgMest gene, suggested that the function of BgMest was conserved in amphibians. However, the phylogenetic tree of the imprinting gene of the mammals and other vertebrates examined in this study indicated their divergent origins.
基金Supported by grants from the Liaoning Provincial Department of Education(2011196)the Experimental Center Director Fund of Shenyang Normal University(sy201003)~~
文摘Objective] The aim of this study was to investigate the electrophysiological characteristics of spontaneous electrical activities of olfactory bulb in Bufo gargarizans during postembryonic development. [Method] Microelectrode technique was used to record extracellular spontaneous electrical activities of olfactory bulb in B. gar-garizans. [Result] Along with the development of olfactory bulb, the discharge types increased gradual y. Single spontaneous firing enhanced gradual y and it reached the maximum in the metamorphosis phase. The intensity of consecutive single sponta-neous firing changed slightly at the middle of post-embryonic development, but it was stil higher than in the early phase and the adult phase. Consecutive burst spontaneous firing frequency went down over time. [Conclusion] Along with the de-velopment of olfactory bulb, the neuronal excitability increases step by step and the neuronal electrical activities diversify gradualy.
基金Supported by grants from the Liaoning Provincial Department of Education(2011196)~~
文摘[Objective] The aim was to probe into developing changes of spontaneous electrical activities of primordial hippocampus in Bufo bufo gargarizans in postembryonic phase. [Method] Microelectrode technique was used to record extracellularly spontaneous electrical activities of neurons in primordial hippocampus of B.bufo gargarizans in postembryonic phase. [Result] Single, consecutive single, burst, consecutive burst and anomalous spontaneous firing were recorded in primordial hippocampus, in which four kinds of spontaneous firings were recorded in forepart of postembryonic development except the anomalous spontaneous firing, and the burst spontaneous firing and consecutive burst spontaneous firing were predominant. The five kinds of spontaneous firings mentioned were recorded in anaphase of postembryonic development and the single and burst spontaneous firing were predominant.Following with the development of primordial hippocampus, the amplitudes of action potential of single firing and consecutive firing enhanced gradually, and it reaches the maximum in the metamorphosis phase; the differences of the frequencies of consecutive single firing and consecutive burst firing were not significant. [Conclusion] Following with the development of primordial hippocampus, the neuronal electrical activities showed diversification, the developmental degree of the primordial hippocampus in the metamorphosis phase was close to the subadult and adult.
基金Liaoning Provincial Department of Education-Funded Project, No. 20068040the Experimental Center of Shenyang Normal University Foundation, No. 2008007
文摘Microelectrode technique was used to record the spontaneous electrical activities of the neurons in olfactory bulb of the Bufo bufo gargarizans, both in hibernation and after hibemation. This study investigated the electrophysiological characteristics of amphibian olfactory bulb in the period of hibernation and after hibernation and its effects on the start of hibernation and spontaneous awakening. The research showed four forms of spontaneous firings： single spontaneous firing, burst spontaneous firing, irregular spontaneous firing and consecutive single spontaneous firing. The single spontaneous firing includes slow depolarized spontaneous firing and fast depolarized spontaneous firing, and the slow depolarized spontaneous firing occurs only during the hibernation period. In hibernation, the low amplitude and low frequency firing with a longer duration may be relevant to maintaining the tonicity of the central nervous system in toads that are in hibernation, and this kind of firing may also provide an excited basis for their arousal from hibernation. After hibernation, the amplitude and frequency of firing increase, but the firing duration gets shorter. This form of short-term firing, which may be a phenomenon of sensory neurons fast adapting, is one of the neuronal mechanisms for the arousal of hibernating animals.
基金supported by National Natural Science Foundation of China(No.81102518)Postdoctoral Granted Financial Support(No.20110490915)the Guangdong High Level Talent Scheme(R.W.J.)
文摘Three new C-3 dehydrated bufadienolides were isolated from the venom of Bufo bufo gargarizans. Their structures were elucidated as 5β,12β-12,14-dihydroxy-11-oxobufa-3,20,22-trienolide （1）, 5β,12β- 12,14-dihydroxy-11 -oxobufa-2,20,22-trienolide （2）, and 5β,12β-12,14-dihydroxy-11 -oxobufa-2,20,22- trienolide （3） on the basis of extensive spectroscopic analysis, especially 1D NMR and 2D NMR data. In addition, all three compounds were tested for their cytotoxic activities against A549 and HepG2 cancer cell lines. Compounds 2 and 3 showed significant cytotoxicities with IC50 values less than 10 μmol/L on both cancer cells.
基金supported by the National Natural Science Foundation of China(31101633)the Innovative Team Foundation of China West Normal University
文摘In many anurans, the forelimb muscles of males are used to grasp females and are often heavier than those of females despite the larger female body size. Such sexual dimorphism in forelimb musculature is thought to result from sexual selection. In addition, the hindlimbs of frogs and toads play an important role in the reproductive process as amplectant males can expel rivals with robust hindlimbs through kicking. In this study, the sexual dimorphism in dry mass for six hindlimb muscles of the Asiatic toad （Bufo gargarizans） was investigated. The results showed that, when controlled for body size, the hindlimb muscle mass of males significantly exceeded that of females for every muscle. The hindlimb muscle mass of amplectant males was also significantly larger than that of non-amplectant males. These results suggested that if strong hindlimb muscles could improve mating success of males, sexual selection would promote the evolution of dimorphism in this character.
基金supported by the National Construction Project of Traditional Chinese Medicine
文摘Two new bufotoxins,tolocinobufagin-3-succinoylarginine ester and tolocinobufagin-3-hemisuberate, were isolated from the skin of Bufo bufo gargarizans Cantor.Cinobufagin-3-hemisuberate was also isolated from the natural source for the first time.Their structures were established using spectroscopic methods.
文摘Three anti-keratin MAbs were used to identifykeratins expressed in early embryos of Bufo bufogargarizans.MAb AF5 recognized three polypeptides ofkeratin in oocytes,fertilized eggs,up to neurula withMr of 68,65 and 60Kd respectively.At tailbud stage,three other keratins(62,58 and 54Kd)began to expressand could be detected by AF5.MAbs D10 and K12 gavedifferent results,both of them could identify four keratin-like molecules with unusual molecular weights(Mr 98,95,30 and 27 Kd).Moreover,D10 could also detect a 54 Kdkeratin in neurula and tailbud stage embryos,while K12could reveal,beside 54Kd keratin,other four more kera-tins(68,65,62 and 60 Kd).The possible interpretation ofthese results and their implications are discussed.
文摘The taxonomic status of Bufo species in East Asia,particularly those closely related to B.gargarizans,has been controversial for over half a century,and recent molecular studies further fueled the dispute.Whether B.andrewsi,B.bankorensis,B.minshanicus,B.sachalinensis,B.tibetanus,and B.tuberculatus constitute valid species or are geographic or ecological variants of B.gargarizans is at the centre of the discussion.Most of these forms possess morphological diagnostic traits,but those differences are minimal and often inconsistent.Molecular data produced many contradictory patterns.Lack of clear diagnostic characters,different usage or definition of various names,mis-identified specimens,limited amount of data or samples,and frequent inter-specific hybridization may all have contributed to the current controversies.Some contradiction may also result from differences between similarity-based clustering and gene tree-based branching patterns.Nevertheless,a dominant allopatric differentiation pattern within this species complex is apparent,and several regional population groups have been identified.Some of the groups resemble old names(e.g.B.minshanicus,B.tibetanus),while others are new.These groups may represent geographic or ecological variants,incipient species,or valid species,and the current data do not warrant a convincing taxonomic revision.To move forward,a single study with comprehensive sampling and genomic data is needed to establish a solid framework,which will define naturally existing population clusters/lineages,and detect their levels of divergence and approximate geographic boundaries.Morphological and ecological examination will follow to understand their biology,determine their taxonomic status,and identify consistent diagnostic characters if necessary.
基金supported by the National Natural Science Foundation of China(Grant Nos.41541002 and 31372183)Natural Science Foundation of Zhejiang Province(Grant No.LY13C030002),China
文摘Relatively little is known about the relationship between Bufo gargarizans populations from Zhoushan Archipelago and nearby continental regions on the Pacific coast of eastern China.In this paper,155 new specimens of B.gargarizans from Zhoushan Archipelago and adjacent continents and 71 published specimens of B.gargarizans from China's Mainland were studied.Phylogeographical and dating analyses of B.gargarizans were performed using mitochondrial DNA sequencing with a length of 1436 bp.A mt DNA tree that indicated seven major clades was obtained.The earliest split in the mt DNA tree corresponding to the divergence of populations from the western highland region occurred approximately 4.0 million years ago（mya）.A subsequent clade occurred about 3.4 mya,with cladogenesis continuing toward the end of the Pleistocene.The continental clades were distributed in the western,central and northeastern regions of China.Zhoushan Archipelago clades consisted of two largely geographically overlapping subclades with the mt DNA divergence time of 0.73 mya.These results indicated there was extensive dispersal after vicariance.The B.gargarizans populations on Zhoushan Archipelago most probably originated from populations in nearby eastern continental regions of China.It was concluded that geological uplifting during the Pliocene and several sea-level changes in Pleistocene might have influenced the divergence and population demographical history of this species.
文摘【目的】探究无尾两栖类变态前后身体大小、应激反应和免疫功能与特定生活史阶段的关系。【方法】以中华蟾蜍(Bufo gargarizans)为研究对象,测定其从33~35期蝌蚪发育至46期幼蟾过程中的体质量、体全长、各型白细胞的百分比、嗜中性粒细胞与淋巴细胞的比值(ratio of neutrophils to lymphocytes,N/L),以及植物血凝素(phytohemagglutinin,PHA-P)反应的变化。【结果】(1)中华蟾蜍的体质量和体全长均在38~39期最高,46期最低(P<0.05);体质量与体全长的比值46期最高,41~42期最低(P<0.05)。(2)PHA-P最大反应值均出现于注射后3 h,其中33~35期、37期和38~39期的反应值均显著高于41~42期和46期(P<0.05)。(3)单核细胞、淋巴细胞和嗜碱性粒细胞的百分比在不同发育阶段无显著变化(P>0.05);嗜中性粒细胞的百分比37期最高,33~35期其次,均显著高于38~39期(P<0.05);嗜酸性粒细胞的百分比46期最高,37期和38~39期其次,均显著高于41~42期(P<0.05)。N/L在37期最高,33~35期其次,均显著高于38~39期(P<0.05)。【结论】中华蟾蜍从水生向陆生生活过渡过程中,应激反应能力在变态前期最高,临近变态期最低,免疫系统不同组分被激活或受抑制的时间段不同,这些生理特征的“错配”可能是其登陆成功率低的主要原因之一。
