3种文昌鱼的同工酶表型比较

采用垂直平板不连续聚丙烯酰胺凝胶电泳和生化染色方法比较白氏文昌鱼(Branchiostoma belcheri)、日本文昌鱼(B.japonicum)和佛罗里达文昌鱼(B.floridae)的4种同工酶(苹果酸脱氢酶MDH、超氧化物歧化酶SOD、酯酶EST、淀粉酶α-AMY)的酶谱,结果显示4种同工酶酶带的数目、染色深浅及迁移率在3种文昌鱼之间的差异比较明显,可作为鉴定不同种文昌鱼的依据,但同种文昌鱼的雌雄之间以及性腺成熟前后的同工酶酶谱的差异不明显.     

白氏文昌鱼和日本文昌鱼的营养成分分析与评价

分析了两种文昌鱼的营养成分,结果表明白氏文昌鱼(Branchiostoma belcheri)的水分、粗蛋白、粗脂肪和灰分分别占鲜质量的81.35％、13.31％、0.82％和2.13％;而日本文昌鱼(B.japonicum)的分别占82.65％、12.76％、0.56％和1.98％.白氏文昌鱼的氨基酸总量、必需氨基酸和鲜味氨基酸分别占干质量的58.91％、20.71％和26.20％,而日本文昌鱼的分别占64.20％、22.62％和28.16％.根据氨基酸评分(AAS)或化学评分(CS),白氏文昌鱼和日本文昌鱼的第一限制性氨基酸均为色氨酸,必需氨基酸指数(EAAI)分别为60.34和64.78.白氏文昌鱼和日本文昌鱼饱和脂肪酸分别占总脂肪酸质量的26.0％和31.9％,不饱和脂肪酸分别占47.20％和46.8％,其中ω-3不饱和脂肪酸含量较高,它们都是营养价值较高、味道鲜美的海产品.     

厦门文昌鱼资源管理与经济发展

厦门拥有的珍贵文昌鱼资源．是自然恩赐的一笔不可多得的财富，但由于过去一个时期的开发不当和管理乏力，厦门文昌鱼资源日趋衰败．亟待拯救。继2004年，厦门海洋生物科研人员首次取得文昌鱼人工繁殖成功之后，2005年。厦门市水产研究所的《文昌鱼人工育苗技术》课题研究又获重大突破，人工培育出约80万尾体长0．45～0．70cm的文昌鱼鱼苗。这一成果对养护，恢复濒危的、名噪世界的厦门文昌鱼资源，无疑将产生积极的影响。如何管理好厦门文昌鱼资源？如何合理开发利用厦门文昌鱼资源发展经济？便成为随之而至的议事议题．     

青岛文昌鱼促甲状腺激素受体(TSHR)蛋白的融合表达及鉴定

为表达青岛文昌鱼促甲状腺激素受体(the thyrotropin receptor,TSHR),构建了TSHR基因的原核表达载体pGEX-4T-1-TSHR,并将其转化入大肠杆菌DH5α中.采用IPTG诱导蛋白表达,并用SDS-PAGE分析表达蛋白.利用抗TSHR多克隆抗体进行Western blot检测.结果表明重组质粒在大肠杆菌DH5α中表达,融合蛋白的分子大小约为76kDa,Western blot检测说明得到的融合蛋白为TSHR蛋白,成功构建了文昌鱼TSHR基因的原核表达载体.     

以人工海水和天然海水饲养的文昌鱼生长发育的比较

将 2 0 0尾文昌鱼随机分为 2组 (每组 10 0尾 ) ,分别以人工海水和天然海水在实验室内进行饲养 ,以实验前后文昌鱼的体长、体质量、成活率和性腺直径作比较 ,初步评价人工海水对文昌鱼生长发育的影响 ,并在其生殖季节 ,观察其产卵、排精的情况 .结果表明 :两种不同海水饲养的文昌鱼其成活率、平均体质量及平均性腺直径均无显著差异 ,2组文昌鱼性腺发育基本同步 .但天然海水饲养的文昌鱼体长的增长则明显大于人工海水组 .     

罗源湾文昌鱼幼体的发现

文昌鱼是名贵的海产品,也是教学和科研的好材料,我国现有文昌鱼资源量不多,最负有盛名的厦门刘五店文昌鱼资源也日益衰竭。作者在1986年11月至1987年10月罗源湾浮游动物调查期问,首次在罗源湾发现文昌鱼幼体,经鉴定为厦门文昌鱼(Branchi-     

青岛文昌鱼NADH脱氢酶亚基I基因片段的克隆

NADH脱氢酶亚基I是细胞电子传递链的主要成员之一，采用简并引物PCR方法获得青岛文昌鱼NADH脱氢酶亚基I基因片段，将基氨基酸序列与其他生物如佛罗里达文昌鱼，斑马鱼，爪蟾等无脊椎和脊椎动物NADH脱氢酶亚基I基因相应片段进行了同源性分析，均显示较高的同源性，研究结果证实青岛文昌鱼作为脊索动物的代表之一，与脊椎动物有着较近的亲缘关系，是从无脊椎动物到脊椎动物的过渡类型。     

文昌鱼的生境与资源保护

文昌鱼是海产珍稀动物,体长一般40-50毫米,在厦门采集的标本,最长只有67毫米.身体半透明,营穴居生活,属底栖类生物.文昌鱼是无脊椎动物进化到脊椎动物的过渡类型,分类位置应排在脊索动物门,头索动物亚门,头索纲.在文昌鱼身上可见到脊椎动物祖先的主要特征:脊索、神经管和鳃裂.因此,达尔文称文昌鱼的发现可以看到5亿年前脊椎动物始祖的模样.文昌鱼是中学生物教学和实验的重要材料.最近,科学家从文昌鱼身上追踪到动物生殖激素演化线索     

河北省东部海区文昌鱼的栖息环境及形态特征

描述了河北省东部海区文昌鱼的栖息环境及体长、体高、生殖腺数目、肌节数目、背鳍条数目及口笠触手数目等形态特征，并与模式种－－厦门文昌鱼（ＢｒａｎｃｈｉｏｓｔｏｍａｂｅｌｃｈｅｒｉＧｒａｙ）做了相应比较。结论认为，河北省东部海区文昌鱼与厦门文昌鱼同属一种，可能是该种不同的地理亚种。     

低浓度镉、锌暴露对白氏文昌鱼的毒性累积及其几种重要酶活性的影响

采用亚慢性毒性实验研究了镉、锌对白氏文昌鱼(Branch iostoma belcheri)(简称文昌鱼)的毒性累积效应及体内超氧化物歧化酶(SOD)活性、乙酰胆碱酯酶(AChE)活性、磷酸酶活性及脂质过氧化产物丙二醛(MDA)含量的影响,探讨了亚致死浓度镉、锌胁迫下文昌鱼的生理生化响应.研究结果表明,镉和锌对文昌鱼的96 h半致死浓度(LG0)分别为4,60和2.26 mg/L,相比之下锌对文昌鱼的毒性更大.实验采用理论上的镊、锌安全浓度(1/10 96 h LC50)对文昌鱼进行7d的亚慢性暴露,随着暴露时间的推移,镉在文昌鱼体内呈线性增加,而锌的含量则与对照组无显著性差异,表明文昌鱼对锌的调节能力大于镉.7d亚慢性毒性实验表明文昌鱼体内的AChE活性随着金属暴露时间的延长持续下降,至第7天时镉和锌对AChE活性的抑制率分别达65％和79％;脂质过氧化产物MDA水平在金属暴露初期即达到极显著水平,随后稍有下降且镉对文昌鱼体内活性氧的诱导作用大于锌;SOD活性在暴露中期受到显著抑制,可能是由于体内过氧化程度过高抑制其活性,之后逐渐恢复.文昌鱼体内的碱性磷酸酶(AKP)活性在镉或锌暴露的第1天被显著诱导,之后恢复至对照水平;酸性磷酸酶(ACP)活性随镉暴露时间延长,呈现先升高再下降的趋势,而锌对ACP活性无显著影响.实验结果表明即使是很低浓度的镉、锌都会对文昌鱼的神经系统及抗氧化等防御系统造成一定的损伤.     

用快速蛋白液相层析（FPLC）法纯化文昌鱼酸性磷酸酶

从厦门文昌鱼体内提纯了一种酸性磷酸酶，用快速蛋白液相层析法（ＦＰＬＣ）的Ｓｕ－ｐｅｒｏｓｅ１２柱和ＭｏｎｏＳ柱对其进一步纯化，用聚丙烯酰胺凝胶电泳和ＦＰＬＣ的Ｓｕｐｅｒｏｓｅ１２柱鉴定为单一纯的酶制剂．它的分子量为５２０００，经ＳＤＳ聚丙烯酰胺凝胶电泳鉴定该酶为二聚体．酶的提纯倍数为６１２．５２．     

文昌鱼酸性磷酸酯酶色氨酸残基的修饰

从厦门文昌鱼(Branchiostonia belcheri Gary)分离纯化获得聚丙烯酰胺胶电泳单一蛋白区带的酸性磷酸酯酶(EC3.1,3.2)应用化学修饰方法,荧光以及紫外-可见光谱的变化,探讨Trp残基与酶活力的关系,被NBS修饰的Trp基团仅有一个Trp残基被氧化时,酶活力丧失90％,该Trp残基为ACPase表现活力所必需,而且优先被氧化、从光谱扫描(230～600nm)结果表明,经NBS修饰以后的酶构象发生变化,文昌鱼ACPase的Trp残基和酶分子上的铁离子等基团均为酶活力的必需基团,推测两者可能以配位结合,共同维持酶活力中心的构象。     

Distribution of α-MSH-like immunoreactive cells in the nervous system, Hatschek''''s pit and other tissues of amphioxus, Branchiostoma belcheri

Immunohistochemical localization of a-melanocyte-stimulating hormone (α-MSH) in the nervous system, Hatschek's pit and other tissues of amphioxus (Branchiostoma belcheri) was performed using the antibody against synthetic α-MSH. The results revealed that α-MSH-like immunoreactive cells were distributed at the dorsal side and ventral side of brain vesicle, the dorsal side and the surrounding of nerve tube, and in the epithelial cells of Hatschek's pit, the zone 1, 3, and 6 of endostyle and gut. The immunoreactive substance was also found in the primary oocytes of the small and large growth stage of ovary and early stage spermatogenic cells in testis. These findings indicate that α-MSH is an ancient and highly conserved hormone and it is extensively distributed in amphioxus. Although Hatschek's pit in amphioxus does not have a structure of the intermediate lobe of vertebrate adenohypophysis, it has already hosted α-MSH-like endocrine cells, implying that the functional differentiation of α-MSH-like cells occurred earlier than the differentiation of the tissue structure. The results of the present study provided a new evidence for the endocrinology of Hatschek's pit and for the origin and evolution of vertebrate adenohypophysis.     

Synergistic actions of complement and lysozyme in clearance of Escherichia coli from amphioxus Branchiostoma belcheri

Amphioxus appears lacking free circulating blood cells. How it clears invading pathogens from its body remains unknown to date. We demonstrate here that amphioxus Branchiostoma belcheri is capable of efficiently eliminating the invading bacterium Escherichia coli from its humoral fluid, and the complement and lysozyme are both involved in the elimination of the invading pathogen. Both the complement and lysozyme act in concert against the invading bacterium, but the complement appears playing a more dominant role than the lysozyme.     

Distribution of CRH-and ACTH-like immunoreactive cells in amphioxus,Branchiostoma belcheri

Immunocytochemical studies on the nervous system,Hatschek's pit,digestive tract and gonads tissues of an amphioxus(Branchiostoma belcheri)were performed using polyclonal antibodies against human corticotrophin-releasing hormone(CRH)and human adrenocorticotropin(ACTH).The results showed that many CRH-like immunoreactive neurons were distributed specifically on the dorsal side and ventral side of brain vesicle,while a few CRH-like neurons and their fibers in spinal cord.At the same time,the epithelial cells in the basic region of Hatschek's pit were shown immunopositive to CRH antibody.In gonads(ovary and testis),CRH-immunopositive substance was localized in the cytoplasm near oocyte nucleus and in early spermatogenic cells.ACTH-like immunoreactivities were observed specially in the neurons and their protrusions localized on the ventral side of the brain vesicle and in spinal cord,and also in epithelial cells of Hatschek's pit,enteric neurons of digestive tract,oocytes in ovary and in early spermatogenic cells as well.It was found for the first time that CRH-like neurons existed in the middle region of brain vesicle(corresponding to the hypothalamus of vertebrates)and ACTH-like immunopositive cells existed in Hatschek's pit,implying that a control mechanism between brain vesicle and Hatschek's pit maybe had been already built in amphioxus as that in vertebrates.The present study will provide new morphological evidence for the origin and evolution of ACTH.In addition,the immunoreactivities of CRH and ACTH in the digestive tract and gonads suggested other physiological function of CRH and ACTH in amphioxus.     

Characterization and expression of a cDNA, AmphiSDHD,encoding the amphioxus cytochrome b small subunit in mitochondrial succinate-ubiquinone oxidoreductase

In this study, an amphioxus cDNA, AmphiSDHD, encoding the cytochrome b small subunit in mitochondrial succinate-ubiquinone oxidoreductase, was isolated from the gut cDNA library of amphioxus Branchiostoma belcheri tsingtauense. It is 1429 bp in length, with an open reading frame of 465 bp coding for a protein of 154 amino acids. The deduced protein contains a mitochondrial targeting presequence of 65 amino acids rich in basic residues like arginine and hydroxy residues such as serine and threonine. Alignment of the amino acid sequences of AmphiSDHD and other eukaryotic SDHD proteins showed that AmphiSDHD has three transmembrane segments, and includes two histidine residues in the second transmembrane segment that are the putative binding sites for the heme b molecule. The phylogenetic tree constructed suggests that AmphiSDHD appears more closely related to vertebrate SDHD proteins than invertebrate ones. Northern blotting demonstrated that AmphiSDHD is ubiquitously expressed in amphioxus, being in line with the fact that SDHD is a house-keeping protein.     

Characterization and expression of a cDNA, AmphiSDHD , encoding the amphioxus cytochrome b small subunit in mitochondrial succinate ubiquinone oxidoreductase

Succinate ubiquinone oxidoreductase ,alsoknownascomplexII ,isthesmallestenzymecomplexfunctioninginboththetricarboxylicacidcycle(TAC)andtheaerobicrespiratorychainofeukaryoticcellmitochondriaandprokaryoticcells[1] .Itiscom posedoffournuclear encoded proteins ,SDHAorflavoprotein (70kD) ,SDHBoriron sulfurprotein(2 7kD) ,SDHCorCII 3(15kD)andSDHDorCII 4 (7— 9kD)inmosteukaryotes[2 ] .Thetwoproteins ,SDHAandSDHB ,comprisethesuccinatedehydroge nase (SDH) ,anenzymeoftheTACandaperipher…     

文昌鱼Rbx1同源基因的克隆，进化分析和表达图式的研究（英文）

在青岛文昌鱼中首次克隆到一个RING box同源基因,对其进行了序列特征和系统进化学分析,并且研究了该基因的胚胎发育和成体表达图式 。AmphiRbx1演绎的蛋白序列与已知其他无脊椎动物和脊椎动物的同源分子表现出很高的相似性。利用原位杂交和RT PCR技术研究该基因的表达,结果显示AmphiRbx1在胚胎发育各期均有表达,特别是在 卵裂期胚胎和有高速分裂细胞的组织中有很强的表达。实验结果表明,Rbx1基因在进化中相当保守,AmphiRbx1可能在细胞分裂的调节中发挥作用。