魏氏拟尾柱虫腹皮层纤毛器微管胞器的形态及形态发生

应用荧光紫杉醇直接荧光标记和抗α-微管蛋白抗体免疫荧光标记显示,魏氏拟尾柱虫(Paraurostyla weissei)腹面皮层纤毛器微管胞器由口围带、波动膜、额腹横棘毛和左右缘棘毛等纤毛器微管、纤毛器基部附属微管等组成。其中口围带基部微管包括小膜托架、小膜附属微管;额腹横棘毛和左右缘棘毛基部附属微管包括前纵微管束、后纵微管束和横微管束,它们由各自的纤毛器基部向皮层细胞质不同方向发射,形成腹皮层表面下微管网。结果表明,魏氏拟尾柱虫的纤毛器骨架、纤毛器附属结构也是一类以微管蛋白为基本成分的微管胞器,其中缘棘毛基部附属微管具有不同于其他纤毛虫(例如棘尾虫)中所观察到的同种微管胞器的建构特征。形态发生中,前仔虫口围带在老结构位置形成,其结构建成与部分老口围带的更新有关;老缘棘毛的结构物质对新的左、右缘棘毛的发生可能具有定位作用及物质贡献,但此后新的左、右缘棘毛列分别在老缘棘毛的右侧形成,而并非是在老缘棘毛位置分化的。在有些细胞中,新的左缘棘毛左侧另有一列棘毛,这可能是形态发生中老的左缘棘毛退化不完全产生的。     

A Novel Healing Filament in Ciliate Regeneration

The interphase cells of the hypotrich ciliate Paraurostyla weissei possess a complex fibrillar system surrounding basal bodies in the compound ciliary assemblages, cirri and membranelles. During replacement of the ciliature at cell division, transient filaments precede and accompany the development of ciliary primordia and participate in the formation of the fission furrow. Both fibrillar systems are recognized by monoclonal antibody FXXXIX 12G9. We studied regeneration of cellular fragments after transection employing the mAb 12G9 and found a new cytoskeletal structure involved in healing of the excisional wound. The healing filament is formed at the wound edge, distally and in connection with the bases of cirri closest to the wound. It is visible 5 min after transection. Concomitant with development of new ciliary primordia, the healing filament shrinks and finally disappears together with other transient fibers formed in this process. Ultrastructural analysis of immunolabeled regenerating cells revealed that structures recognized by mAb 12G9 contain fine filaments whose packing and arrangement depends on accompanying cytoplasmic elements and the developmental status of a fragment. Assembly of the healing fiber does not depend on microtubules and microfilaments since it develops in cellular fragments exposed to cold, nocodazole, and Cytochalasin D. On Western blots of whole cell and cytoskeletal extracts of P. weissei the 12G9 antibody identified one protein band whose molecular weight corresponds to 60 kDa.     

魏氏拟尾柱虫休眠包囊细胞器的电镜酶细胞化学研究

为研究纤毛虫在休眠状态下细胞生命活动的特征及细胞器的功能,应用电镜酶细胞化学方法显示,魏氏拟尾柱虫（Ｐａｒａｕｒｏｓｔｙｌａ ｗｅｉｓｓｅｉ）休眠包囊中,在自噬泡位置,酸性磷酸酶反应颗粒形成多种形态的泡状体,ＡＴＰ酶反应颗粒聚集形成泡状体或球状体,在分散分嘏的线粒体中于内膜位置形成少数琥珀酸脱氢酶反应颗粒。由所得结果推测,纤毛虫休眠包囊中的自噬泡消化现象是细胞在特殊生理条件下的重要生命活动,是休眠     

Conjugation in the Hypotrich Ciliate,Paraurostyla weissei (Stein): A Scanning Electron Microscope Study*

SYNOPSIS. Conjugation in Paraurostyla weissei has been investigated by scanning electron microscopy. In the course of conjugation, one member of each conjugating pair is resorbed. An organism that is being resorbed always lies to its partner's left and is always fused to its partner's oral region. A mechanism for the development of this asymmetry is proposed, based on the asymmetry of individual Paraurostyla. After resorption is complete, exconjugants enter a rounded, nonmotile stage which lasts several days. Exconjugants at this stage have been compared with cysts and have been found to be dissimilar.     

魏氏拟尾柱虫休眠包囊及其细胞器超微结构的观察

为研究纤毛虫休眠状态下细胞的分化及其胞器的特征,本文以透射电镜术显示,魏氏拟尾柱虫（Ｐａｒａｕｒｏｓｔｙｌａｗｅｉｓｓｅｉ）休眠包囊中,颗粒层壁内有小泡,表膜位置偶见小泡样结构,大部分线粒体以多个相互聚集在一起,自噬泡将线粒体等胞器包裹在内经历消化过程,细胞内膜系统十分发达。作者推测,颗粒层及表厝小泡可能是休眠细胞经由表膜进行物质交换的结构,自噬泡消化现象可能是细胞中物质和能量来源的主要途径。     

The Structure and Morphogenesis of the Ventral Ciliature in Paraurostyla hymenophora*

SYNOPSIS. The structure and morphogenesis of the ventral ciliature of Paraurostyla hymenophora (Stokes) are described. The oral primordium apparently originates in association with transverse cirrus #6, from which it migrates anteriorly simultaneous with kinetosomal proliferation. The primordium eventually forms an elongate ciliary field from which the future opisthe's fronto-ventro-transverse (FVT) and undulating membrane primordial fields arise. Concomitantly, the future proter's FVT primordial field is initiated by the disaggregation of frontal cirri #4, #5, and #6. Primordia then develop simultaneously within marginal and ventral cirral rows by a disaggregation of cirri within the respective rows, and do not give rise to new cirri until the FVT fields complete segregation into discrete cirri. Near the completion of cirral production from the FVT primordia, each ventral cirral primordium (VCP) forms the 2 rightmost transverse cirri. Segregation of new cirri within the marginal cirral primordia and VCP then occurs, eventually replacing all old cirri within their respective marginal and ventral cirral rows. At the end of cortical morphogenesis, all old ciliary organelles, with the exception of the adoral zone of membranelles, are either reorganized or replaced. These results suggest an evolutionary affinity between the ventral and marginal cirral rows and raise questions about the control of the developmental competence of individual primordia.     

三种纤毛虫细胞内酸性磷酸酶的定位观察

利用电镜酶细胞化学方法,对大尾柱虫(Urostylagrandis)、冠突伪尾柱虫(Pseudourostylacristata)、魏氏拟尾柱虫(Paraurostylaweissei)三种纤毛虫细胞内的酸性磷酸酶(ACPase)进行了定位观察。发现在它们体内ACPase的阳性反应颗粒除分布在消化腔隙内独立的泡状结构上和被消化的食物组织中外,在细胞质中的小圆泡内也有分布。所得结果证实了消化腔隙和小圆泡都具有消化功能。作者推测消化腔隙主要消化食物,小圆泡则可能与自身物质(如衰老胞器等)的消化有关;并推测这种消化腔隙与小圆泡共存是纤毛虫消化胞器由食物泡演化为消化腔隙系统的中间形式。此外,在大尾柱虫纤毛内部观察到非溶酶体性的ACPase。     

Production and Characterization of Three Polyclonal Antibodies Raised Against Cyst Wall Proteins of a Hypotrichous Ciliate

ABSTRACT Three polyclonal antibodies raised against Paraurostyla sp. cyst wall polypeptides of molecular weight 110,000 (p110), 66,000 (p66) and 52,000 (p52) have been obtained. The specificity of the antisera was tested by immunoblotting. Anti-p110 antibody detected five bands of 300, 170, 135, 110 and 40 kDa, respectively. Antiserum obtained against p66 recognized only this protein. Anti-p52 antiserum showed reaction for two different bands of 52 and 44 kDa, respectively. The precise localization of these proteins in the cyst wall was assessed by light microscope immunocytochemistry. Anti-p110 antiserum produced a strong positive reaction in both the ectocyst and endocyst. Both anti-p66 and anti-p52 antibodies recognized the ectocyst.     

一种用于观察纤毛虫表膜下结构的扫描电镜样品制备新方法

该实验摸索出通过扫描电镜观察纤毛虫表膜下三维结构的新方法:用适当浓度的KMnO_4作为固定剂,固定虫体细胞表膜,调整固定液的渗透压使细胞在低渗溶液中胀破、细胞质溶出,表膜剥落下来、内外翻转,经脱水、冷冻干燥、喷金后,在扫描电镜下对爽口虫(Climacostomumsp.)、尾草履虫(Paramecium caudatum)及拟尾柱虫(Paraurostyla weissei)的表膜下结构进行了观察。结果表明:利用此方法能够观察到表膜下层次分明而又清晰的三维立体构象。此方法可为纤毛虫表膜及其它细胞质膜的研究提供可借鉴的样品制备新方法。