寄生鱼类的六鞭毛虫超微结构及系统发育

根据原生动物学家协会出版的最新分类方案,六鞭毛虫隶属于原生动物亚界 (Protozoa)六鞭毛虫科 (Hexamitidae) 1,2.       

蓝氏贾第鞭毛虫滋养体超微结构的研究

从实验感染的长爪沙鼠小肠内分离贾第虫滋养体,用SEM和TEM做超微结构观察。SEM见虫体呈纵切为半的梨形。前端钝圆,后端尖细。背部隆起,凹凸不平。体前腹面凹陷形成吸盘,边缘为嵴部。虫体周缘有周翼。本虫共有前、腹、后侧和尾鞭毛各一对,直径为200 nm左右;TEM是吸盘为一不对称的圆盘,由呈顺时针旋转之微管组成,并在嵴部重叠形成上、下叶。吸盘背侧有两个左右对称的细胞核,核间可见轴索。胞质内见许多空泡、纤维物质和中体。     

鲴类寄生六鞭毛虫系统发育的研究

利用分支系统学（Ｃｌａｄｉｓｔｉｃｓ）的原理和方法,选取光镜下的２４个性状,对鲴亚科１７种寄生六鞭毛虫进行了系统发育分析,初步阐明了这１７种六鞭毛虫相互间的亲缘关系。结果还表明,鲴亚科寄生六鞭毛虫的分化较晚;一些明显特征：如杆状条纹,是进化适应的结果,具有系统学意义。还通过对寄生六鞭毛虫在鲴亚科鱼类中的区系分布特点分析,探讨了宿主相互间的亲缘关系。结果表明：寄生六鞭毛虫的区系分布能够反映宿主相互间     

鱼类寄生六鞭毛虫五新种

六鞭毛科(Hexamitidae)属动鞭纲(Zoomastigophorea)、双体目(Diplomonadida).自Moore首次报道寄生于鱼类的六鞭毛虫始,到目前为止,已报道寄生于鱼类的六鞭毛虫,共计30余种,分别隶属于六鞭毛虫属(Hexamit a)和旋核鞭毛虫属(Spironucleus).作者发现五新种,它们是寄生于细鳞斜颌鲴(Xenocypris microlepis Bleeker)的关桥六鞭毛虫(Hexamit a guanqiaoensis sp. nov.)、寄生于黄尾鲴(Xenocypris dividi Bleeker)的梁子湖六鞭毛虫(Hexamita liangzihuensis sp. nov.)和微小旋核鞭毛虫(Spironucleus mi nutus sp. nov.)、寄生于银鲴(Xenocypris argentea Günther)的多形六鞭毛虫(He xamita varformis sp. nov.)和粒状旋核鞭毛虫(Spironucleus granularis sp. nov.).采用蛋白银染色方法,对寄生于鱼类的六鞭毛虫进行了研究.       

鱼类寄生六鞭毛虫的研究（动鞭纲：双滴虫目：六鞭毛科）

本文报道六鞭毛科１８个新种,其中六鞭毛虫属１５种,旋核六鞭虫属３种,其简要形态记述于后,模式标本保存在中国科学院水生生物研究所鱼病学研究室。     

武昌六前鞭虫胞器超微结构的研究

对武昌六前鞭虫胞器的超微结构进行了观察,发现R鞭毛复合体的内下方有分散的微管,两根R鞭毛复合体之间和外方具少量的粗面内质网,而虫体周边分布较多.粗面内质同外周被发达的微管.生毛体与胞核之间有胞咽和小盾结构.胞质中有较多的食物泡,未见到线粒体、高尔基体和表膜下微管结构.另外对粗面内质网的结构、功能以及种的鉴定等方面也作了讨论.       

Prorocentrum属涡鞭毛虫核仁的观察

迄今未能在光学显微镜下观察到Prerocentrum属的涡鞭毛虫有核仁。本文作者用伊红的酒精溶液和用甲基缘—派若宁法染色,也未能在Prerocentrum micans和Proro-centrum cassubica的细胞核中显示出核仁来。但是在用专门为显示单细胞生物的核仁组织者区（NOR）而改进了的Ag—1法进行染色时,这两种涡鞭毛虫的核仁都会被染作鲜明的深褐色或深黑色,而身体的所有其他部份,包括染色体,全都不着色。染色适当时可以看出,实际上只是核仁的中央部分被染上色。在电镜下可见,此时所有的银粒全部是集中在核仁的纤维区中。染色的结果表明,Prorocentrum cassbica只有一个扁园形的小核仁,后者是贴附在核膜上,其NOR通常是作O形或C形。与P.cassubica不同,P.micans的核仁的数量变化很大,可以有一个至七个;其核仁的大小与形状同样也变化很大;其NOR的形状也复杂多变。发现P.micans的核仁数量与个体的生活状况有一定的关联:向老的培养液中加入等量的新的培养液一天以后,具有三个核仁的个体是最多的（占三分之一）,具有4—6个核仁的个体占28.5％,只有一个核仁的个体只占8.6％;加入新培养液三天后,具两个核仁的个体变成是最多的（占38.8％）,具4—6个核仁的个体降为占18.4％;加入新培养液一个月以后,只有一个核仁的个体是最多的（占3     

肠道鞭毛虫群落及在宿主白蚁分类学上的意义

于国内五个常见白蚁种肠道内共记录到十七个鞭毛虫种。鞭毛虫种群具特异性和稳定性。群落相的变异度反映了宿主白蚁亲缘关系的离散度。异域同种白蚁肠道鞭毛虫群落显示稳定的同一相,同属异种白蚁的鞭毛虫群落部分相同;异科异属或同科异属白蚁的鞭毛虫群落绝然相异。 鉴于传统的生物分类法已明显地显示出其片面性及局限性,为此,人们正试图从其它学科领域,各个不同角度去探索能更客观反映各物种在系统发生上关系的新分类法。迄今,精确定性的生化分类、免疫分类和以群体力对象的定量的数量分类等已倪露头角,从而为以形态描述为主的经典生物分类学注入了新的活力。 本文试图通过对白蚁肠道鞭毛虫群落及种群的研究而借以探讨其在宿主白蚁系统分类研究中的潜在意义。     

特殊涡鞭毛虫——尖尾虫染色体与典型涡鞭毛虫染色体的比较研究

我们实验室与上海细胞生物学研究所的有关同志多年来在特殊涡鞭毛虫──尖尾虫（Ｏｘｙｒｒｈｉｓｍａｒｉｎａ）的细胞生物学和生物化学上作了一系列的研究,本文所报道的是这些工作中的一部分。对尖尾虫（Ｏｘｙｒｒｈｉｓｍａｒｉｎａ）的永久浓聚染色体的精细形象以及不同固定方法对其精细形象的影响作了观察,并与人肠道细菌的类核体、典型涡鞭毛虫原甲藻（Ｐｒｏｒｏｃｅｎｔｒｕｍｍｉｃａｎｓ）和鞭毛虫眼虫（Ｅｎｇｌｅｎａｓｐ．）的永久浓聚染色体作了比较。结果表明,细菌的类核体的精细形象受固定方法的影响极大。反之,不同的固定方法对于眼虫染色体的精细形象则看不出有任何显著的影响。至于典型涡鞭毛虫类的染色体,单用ＯｓＯ４或用戊二醛－ＯｓＯ４双固定法固定,都会得到典型涡鞭毛虫类染色体的横带样结构,然而单纯用戊二醛固定,却会得到大不相同的形象。在这方面尖角虫的染色体与一般的涡鞭毛虫类的染色体相距甚远,其染色体的精细形象本身也与眼虫类的染色体较为相似,而与一般涡鞭毛虫类的大不相同。本工作所得到的结果与以前我们在不同方面所得到的结果一致。研究结果全都表明,失足虫与典型涡鞭毛虫有着一系列重大的差异,实际上代表着一个介于一般鞭毛虫类与典型涡鞭毛虫类     

大豆根瘤侵染细胞中一种细胞质内含物的电镜观察

在中国丰收11号大豆根瘤侵染细胞中,我们发现了一种电子密度很高,体积很大,形状为圆形或近似圆形,外面没有界膜,常位于胞间隙附近的特殊的细胞质内含物。高尔基体及其小泡,丰富的粗糙型内质网和核糖体常在它的附近,其中一些核糖体正沉积在它的表面。它主要是由核糖体凝聚而成,高尔基体和内质网在它的形成中也起了一定作用。它的内部含有颗粒状,纤维状,泡状和管状物质。它的出现似乎与侵染细胞固氮有关。     

拟腹吸鳅属鱼类颏吸附器的扫描电镜观察及其亚属划分

扫描电镜下,构成拟腹吸鳅鱼类颏吸附器的若干条皮脊均由许多分别根植于单个上皮细胞表面的爪形突组成。爪形突高１５～２０μｍ,横截面常呈椭圆形,长短轴的４～５μｍ,易脱落,也可增生。它们可能具有吸附基质表面、保护周围味蕾等功能。由于爪形突分布部位的不同和所组成皮脊的形态差异,可明显地分为叠波型和品字型两类。这两类吸附器的种类间同时在味蕾分布、口角须结构和背鳍条及腹鳍条数目等方面也存在相应的差异,代表了两个独立演化的自然类群。本文把腹吸鳅属分成两个亚属,将其中颏吸附器呈品字型的三个种和亚种分离出来,成立品唇吸鳅亚属（Ｌａｂｉｇａｓ－ｔｒｏｍｙｚｏｎ）,其他是叠波型的种类则归属指名亚属（Ｐｓｅｕｄｏｇａｓｔｒｏｍｙｚｏｎ）。     

Relationships between membranous organelles in amoebae studied by electron microscopic cytochemical staining

Summary The intracellular location of a variety of enzymes was studied in Amoeba proteus with the use of electron microscopic cytochemical methods, in an attempt to assess the relationships between different membranous organelles. One group of enzymes, including nucleoside diphosphatases (IDPase, UDPase, GDPase, ADPase), carbamoyl phosphatase, alkaline phosphatase, and BAXD oxidase was localized mainly in the rough endoplasmic reticulum, nuclear envelope, and convex side of the Golgi apparatus. Esterase activity had a similar localization except that the Golgi apparatus was "stained" throughout most of its extent. A second group of enzymes was found in Golgi cisternae and vesicles, and in some vacuoles. This group included acid phosphatase, thiamine pyrophosphatase, and aryl sulfatase. Some enzymes previously detected in cytoplasmic membranes of other cells, including glucose-6-phosphatase, showed little or no activity in amoebae. The results suggest that there are chemical similarities and probable functional relationships between the rough endoplasmic reticulum, the nuclear envelope, and the convex side of the Golgi apparatus. On the other hand, the concave pole of the Golgi apparatus, aggregates of smooth tubules and vesicles, and the cell surface appear more closely related to one another than to the endoplasmic reticulum and the convex side of the Golgi apparatus. The cytochemical similarity between the Golgi apparatus and certain vacuoles such as food vacuoles may reflect the role of the Golgi apparatus in the formation of lysosomes. The locations of reaction products of the various enzymes in amoebae are compared with observations reported for other cell types.Supported by a research grant (VC-169) from the American Cancer SocietyThe author is indebted for technical assistance to Mrs. Sue Thompson and Mrs. Christine Folsom-Kovarik     

莼菜(Brasenia schreberi)表皮腺毛细胞高尔基体中一种内含物的初步研究(简报)

在不经过任何特殊处理的常规生物样品中,高尔基体扁囊(Saccules)及囊泡(Vacuoles)中的内含物在电镜下常为低电子密度,而最近我们在莼菜(Brasenia schreberi)叶柄及叶片的表皮腺毛细胞中观察到带有高电子密度的高尔基体内含物。在扁囊中,这些内含物多呈波浪形(图版Ⅰ,图1)。这种特殊形态的高尔基体内含物以及这种未经任何特殊处理而显示出高尔基体中某些物质的现象是前人没有报道过的,本文就这种内含物的结构、性质以及其染色机制进行了初步探讨。     

约氏疟原虫红外期成熟裂殖体的超微结构研究

用细胞色素氧化酶组织化学方法处理感染了约工疟原虫子孢子的大鼠肝脏,通过透射电镜研究红外期裂殖体的超微结构。在接种子孢子后４８小时的标本中发现一成熟裂殖体,外周仍由一寄生虫质膜包裹,膜下有许多小泡,粗面内质肉、圆形或蚕豆形具明显嵴的线粒体,以及大量成熟裂殖子。     

Ultrastructure of the cortical cell of the interrenal gland of the American bullfrog (Rana catesbeiana)

Summary The cortical cell of the interrenal gland of the American bullfrog, Rana catesbeiana, was examined in the electron microscope. These cells occur in small groups and cords and are quite irregular in shape. The cortical cell is reminiscent of adrenal cortical cells from other vertebrates. Liposomes are variable in size and density. Smooth endoplasmic reticulum is scant in amount and predominantly of the fine tubular type. Mitochondria have vesicular cristae, a dense matrix, and occasionally have blebs, vacuoles, and myelin-like whorls at their surfaces. Intimate morphological relationships are found among the Golgi apparatus, lysosomes, and liposomes, and among Golgi vacuoles, mitochondria, and liposomes. In addition microfibrils are a prominent feature of the cortical cell. The biochemical events of steroidogenesis in amphibia and other vertebrates are discussed in relationship to the organellar interrelations found in the bullfrog interrenal cortical cells. Based on the available chemical and morphological information a scheme is proposed of movement of the steroidal intermediates through the cell that tentatively identifies the localizations of the various enzyme systems involved in corticosteroidogenesis from acetate to corticosterone and aldosterone.Supported in part by N.I.H. Grant RR 06138. Health Sciences Advancement Award.     

A missense mutation in the vacuolar protein GOLD36 causes organizational defects in the ER and aberrant protein trafficking in the plant secretory pathway

A central question in cell biology is how the identity of organelles is established and maintained. Here, we report on GOLD36, an EMS mutant identified through a screen for partial displacement of the Golgi marker, ST‐GFP, to other organelles. GOLD36 showed partial distribution of ST‐GFP into a modified endoplasmic reticulum (ER) network, which formed bulges and large skein‐like structures entangling Golgi stacks. GOLD36 showed defects in ER protein export as evidenced by our observations that, besides the partial retention of Golgi markers in the ER, the trafficking of a soluble bulk‐flow marker to the cell surface was also compromised. Using a combination of classical mapping and next‐generation DNA sequencing approaches, we linked the mutant phenotype to a missense mutation of a proline residue in position 80 to a leucine residue in a small endomembrane protein encoded by the gold36 locus ( At1g54030 ). Subcellular localization analyses indicated that GOLD36 is a vacuolar protein and that its mutated form is retained in the ER. Interestingly also, a gold36 knock‐out mutant mirrored the GOLD36 subcellular phenotype. These data indicate that GOLD36 is a protein destined to post‐ER compartments and suggest that its export from the ER is a requirement to ensure steady‐state maintenance of the organelle’s organization and functional activity in relation to other secretory compartments. We speculate that GOLD36 may be a factor that is necessary for ER integrity because of its ability to limit deleterious effects of other secretory proteins on the ER.     

褶爪沪蚖假眼的电镜观察

褶爪沪蚖(Huhentomon plicatunguis Yin)假眼为梨形隆起,表面具纵向条纹和沟缝;内、外表皮之间形成假眼腔,腔的后半部有一条由内表皮突出形成的龙骨;假眼下有3个感觉细胞,各伸出一条纤毛树突,经假眼后端的通道进入假眼腔,逐渐伸展成片层状,其末端与沟缝相通.观察结果表明其假眼结构与华山夕蚖假眼甚为接近.     

Virus-neuron interactions in the mouse brain infected with Japanese encephalitis virus

The virus-host interactions between Japanese encephalitis (JE) virus and mouse brain neurons were analyzed by electron microscopy. JE virus replicated exclusively in the rough endoplasmic reticulum (RER) of neurons. In the early phase of infection, the perikaryon of infected neurons had relatively normal-looking lamellar RER whose cisternae showed focal dilations containing progeny virions and characteristic endoplasmic reticulum (ER) vesicles. The reticular RER, consisted of rows of ribosomes surrounding irregular-shaped, membrane-unbounded cisternae and resembled that observed in JE-virus-infected PC12 cells, were also seen adjacent to the lamellar RER. The appearance of the reticular RER indicated that RER morphogenesis occurred in infected neurons in association with the viral replication. The fine network of Golgi apparatus was extensively obliterated by fragmentation and dissolution of the Golgi membranes and their replacement by the electron-lucent material. As the infection progressed, the lamellar RER was increasingly replaced by the hypertrophic RER which had diffusely dilated cisternae containing multiple progeny virions and ER vesicles. The Golgi apparatus, at this stage, was seen as coarse, localized Golgi complexes near the hypertrophic RER. In the later phase of infection, RER of infected neurons showed a degenerative change, with the cystically dilated cisternae being filled with ER vesicles and virions. Small, localized Golgi complexes frequently showed vesiculation, vacuolation, and dispersion. The present study, therefore, indicated that during the viral replication the normal lamellar RER which synthesized neuronal secretory and membrane proteins was replaced by the hypertrophic RER which synthesized the viral proteins. The hypertrophic RER eventually degenerated into cystic RER whose cisternae were filled with viral products. The constant degenerative change which occurred in the Golgi apparatus during the viral replication suggested that some of the viral proteins transported from RER to the Golgi apparatus were harmful to the Golgi apparatus and that increasing damage to the Golgi apparatus during the viral replication played the principal role in the pathogenesis of JE-virus-infected neurons in the central nervous system.     

Substructure of cisternal organelles of neuronal perikarya in immature rat brains revealed by quick-freeze and deep-etch techniques

Summary Membrane-bounded organelles possessing cisternae, i.e., rough endoplasmic reticulum and Golgi apparatus, in immature rat central neurons were examined by quick-freeze and deep-etch techniques to see how their intracisternal structures are organized and how ribosomes are associated with the membrane of the endoplasmic reticulum. Cisternae of endoplasmic reticulum, 60–100 nm wide, were bridged with randomly-distributed strands (trabecular strands, 12.5 nm in mean diameter). Luminal surfaces of cisternae of the endoplasmic reticulum were decorated with various-sized globular particles, some as small as intramembrane particles, and others as large as granules formed by soluble proteins seen in the cytoplasm. A closer examination revealed much thinner strands (3.3. nm in mean diameter). Such thin strands were short, usually winding toward the luminal surface, and sometimes touching the luminal surface with one end. Ribosomes appeared to be embedded into the entire thickness of cross-fractured membranes of endoplasmic reticulum, that is, their internal portions appeared to be situated at almost the same level as the cisternal luminal surface. From the internal portion of ribosomes, single thin strands occasionally protruded into the lumen, suggesting that these thin strands were newly synthesized polypeptides. A horizontal separation within ribosomes appeared to occur at the same level as the hydrophobic middle of the membrane of the endoplasmic reticulum. Interiors of the Golgi apparatus cisternae, which were much narrower than cisternae of endoplasmic reticulum, were similarly bridged with trabecular strands, but the Golgi trabecular strands were thinner and more frequent. Their cisternal lumina were also dotted with globular particles. No identifiable profiles corresponding to the thin strands in the endoplasmic reticulum were observed. Golgi cisternae showed a heterogeneous distribution of membrane granularity; the membrane in narrow cisternal space was granule-rich, while that in expanded space was granule-poor, suggesting a functional compartmentalization of the Golgi cisternae.