海洋尾丝虫无性生殖期间口器发生的再研究

利用蛋白银技术研究了海洋纤毛虫—海洋尾丝虫无性生殖期间的口器发生过程。结果显示其口器发生与已知的同属种类具相似的过程和形式。其口器发生及演化的基本模式可表示如下 :后仔虫的小膜 1、小膜 2来源于老口侧膜后段的增殖 ;后仔虫的口侧膜及盾片来源于老口侧膜前段的增殖 ;后仔虫的小膜 3来自于老口区盾片的增殖 ;前仔虫的口侧膜及盾片来源于老口侧膜 ,三片小膜在口器发生过程中被保留。文中根据现有的形态发生资料对尾丝虫科的系统关系进行了探讨     

海洋纤毛虫--冠帆口虫的口器发生

对海洋盾纤目纤毛虫,冠帆口虫(Pleuronema coronatum)无性分裂期间口器的发生过程做了跟踪观察。结果显示其口器发生与已知的同属种普氏帆口虫具相似的过程。其口器发生及演化的基本模式可简述如下：老口区的三片小膜经历一个分化和移行过程;前仔虫的口侧膜来源于老口区的口侧膜;后仔虫的小膜1～3与口侧膜均来源于老的口侧膜;在口器发生过程中,前、后仔虫口侧膜的后端均形成一个相应的盾片区,其内的毛基粒在进入营养期之前被完全吸收[动物学报49(6)：829～834,2003]。     

尖前口虫的口器发生研究(纤毛门, 膜口目)

研究了咽膜类纤毛虫尖前口虫无性生殖期的核器及口器的演化.其发生特征为;1)新的口原基形成于原前庭动基列与口侧膜间,表观为原口侧膜分裂而致;2)随着形态发生的进行,由口原基依次演化出后仔虫的三片咽膜、口侧膜和三条前庭动基列;3)原口器完全被前仔虫所继承;4)体纤毛器在整个形态发生过程中一直保持双动基列结构.       

暗尾丝虫的形态与形态发生研究

本工作采用Chatton-Lwoff氏银浸法及Wilbert氏蛋白银染色法研究了淡水纤毛虫暗尾丝虫Uronema nigricans(Muller,1786)的形态、核器、纤毛下器、银线系及详细的形态发生过程。结果显示其口器发生与已知的同属种类海洋尾丝虫具相似的过程及形式。其口器发生及演化的基本模式可表达成: 前仔虫:原口侧膜→口侧膜,盾片; 后仔虫:原口侧膜→口侧膜,第1小膜,第2小膜,盾片; 原盾片→第3小膜。 文中另外列表比较了本属与其它属的形态发生特征,并据此建立了一新科,拟梭虫科。     

毛尾刺虫无性生殖周期中的形态和形态发生

利用蛋白银染色法研究了毛尾刺虫的形态及无性生殖周期中的形态发生,其过程为：（１）后仔虫口原基出现在左缘棘毛内侧深层,其内的毛基体组装成整齐排列的小膜并分化成新ＡＺＭ１,ＡＺＭ２和口侧膜,（２）前仔虫口原基出现在老仔虫ＡＺＭ２之前方深处,其随后发育成前仔虫的ＡＺＭ２口侧膜及ＡＺＭ１的一部分,并更新老结构的ＡＺＭ１中第７－１１片小膜,（３）额腹横棘毛原基为５列,分别以３：３：２：２：３方式分化最终产出     

悬游双眉虫(原生动物,纤毛门)无性生殖期间的形态发生

应用蛋白银染色技术研究了悬游双眉虫青岛种群无性生殖期间皮层结构和核器的演化过程,其主要特征为:后仔虫口原基独立地出现于紧靠虫体左侧第一根横棘毛的皮层下小龛,其中毛基粒不参与其它棘毛原基的形成;老的口围带发生后半部的局部重建而非整个的由前仔虫简单继承;在前仔虫中,波动膜原基来自老结构的反分化,而在后仔虫中则来自口原基;所有棘毛原基均为独立发生并与老结构没有任何关系;在前仔虫中,口棘毛(即左侧第一根额棘毛)来自于波动膜的反分化,而在后仔虫中则为独立发生;背触毛列于老的结构当中产生,并由最右一列原基演化出3根尾棘毛;两大核片段的改组带从一端向另一端移动 ,并随着两者的融合而消失.文中同时对前人有关该属发生模式的若干存疑问题做了探讨 [动物学报 54(3):517-524,2008].     

急纤虫Tachysoma pellionella无性生殖周期中核器和纤毛器的演化

应用能同时显示纤毛虫的皮膜结构及核器的蛋白银染色方法,研究了急纤虫Tachysoma pellionella的形态及其无性生殖周期中核器和纤毛器的发育演化过程。其中的形态发生过程是:(1)大核改组带出现后,在口围带(AZM)和腹棘毛VC4、VC5之间形成一条细线,于细线中发生许多成群的毛基体,逐渐演变成为后AZM原基区。最终,原基区颗粒组装成一片片整齐排列的小膜,它们构成为新AZM。老AZM也伴随着由基部向前更新,(2)在额棘毛FC5-FC8和腹棘毛VCl-VC3全部瓦解时紧接着产生前、后波动膜原基和新棘毛原基区,并发生波动膜的分化,棘毛的分化、移动和定位过程;(3)左、右缘棘毛原基的发育形式相同,但右缘棘毛原基的发育稍早。在右缘棘毛列中的第2(或第3)根和约第16根棘毛、左缘棘毛列的第1根和约第17根棘毛开始,随老棘毛基部的瓦解,于老棘毛基部位置各产生前、后两部分新缘棘毛原基,左、右每部分原基各占据了约六个老棘毛基部位置后分别朝所在的老棘毛列的外侧、内侧向后伸展开来;(4)在第1—3列背触毛中分别于每列之前、后两部分的中部范围产生前、后第1—3列新原基,每列原基向其两端伸展替代老背触毛列,它们后来成为前、后仔虫的相应的第1—3列新背触毛。接着在前,后各第3列背触毛原基后端发生前、后第4列原基,并稍偏向第3列原     

四核舍太虫的细胞发生学与Helix E10-1二级结构分析

利用蛋白银染色技术,观察和研究海洋游仆虫-四核舍太虫Certesia quadrinucleata(纤毛门,游仆目)二分裂期间的形态发生学。其主要特征如下:(1)老口围带完全被前仔虫继承;(2)后仔虫口原基独立产生于皮膜深层;(3)老口侧膜参与前仔虫口侧膜原基形成,前后仔虫的口侧膜原基均发生于细胞表面, 向前贡献出第一根额腹棘毛;(4)额-腹-横棘毛以初级5原基模式产生, 且以"3:3:3:3:3"的方式分化出新的棘毛;(5)背触毛与左缘棘毛原基均来自老结构, 无尾棘毛产生。研究首次给出了背面纤毛器的发生图示,为进一步探讨舍太虫的系统地位提供了一份补足性的发生学基础资料。游仆目纤毛虫的核糖体小亚基基因HelixE10-1区域二级结构一共存在9种模式, 该区域序列长度的变异性揭示了游仆目纤毛虫在进化中可能处于比较特殊的地位。       

腹毛目纤毛虫皮膜演化的一种特殊形式—卵圆急纤虫无性二分裂期间的形态发

对海洋纤毛虫卵圆急纤虫无性分裂过程中的形态发生了做了跟踪观察,结果表明,该种的皮膜演化表现了一系列在腹毛目种类中所罕见的特征;１．新老口围带有一临时性汇联为一的阶段;２．左右缘棘毛原基分步出现,即明显的不同步现象;３．大核的改组在细胞分裂开始前即已完成;４．本种后仔虫之棘毛原基的分化既非独立发生又非来自于老结构的反分化,而是紧靠口原基的一侧向外分衍并极可能是孤立地发展而成;５．老的波动膜在形态发生     

卡龙游仆虫无性生殖期间的形态发生学研究：原生动物,纤毛虫

卡龙游仆虫为海洋中自由生纤毛虫,利用银染法对该种二分裂期间的形态发生学进行了初步的研究,其主要过程为：１．伴随大核改组带的出现和ＤＮＡ复制开始,口原基发生于老口围 方皮膜下一龛腔内,后由前至后组装成围口小膜而演化为后ＡＺＭ。老口围带及口侧膜在原位被被前仔虫继承;２．体棘毛场首先出现两组棘毛原基,其随后各自独立演化成９根前、后仔虫的额－腹－横棘毛;３．缘棘毛原基也为独立发生,初为单一,后断裂为二并分     

Morphology and Morphogenesis of Two Species of the Genus Lembadion (Ciliophora, Oligohymenophora): Lembadion lucens and Lembadion bullinum

ABSTRACT. The morphology and morphogenesis of two species of the genus Lembadion, L. lucens and L. bullinum , are described. In both species, left and right ventral kineties converge behind the mouth forming a postoral suture. Buccal infraciliature is formed by one polykinety and two very close paroral kineties (inner and outer). During stomatogenesis, the new oral structures originate from the paroral kineties. The inner paroral kinety forms the new adoral polykinety and regenerates the outer paroral kinety of the proter, while the paroral kineties of the opisthe originate from the outer paroral kinety of the parental cell. Somatic proliferation starts before the stomatogenesis at the equatorial level of the cell, and extends towards the poles forming an equatorial band. Two large invariant zones, anterior and posterior, remain in the dividing cell. Moreover, the kinetodesmal fibers disappear in the proliferation band during the bipartition (fission) process.     

Morphogenesis in Conchophthirus curtus: a Study of the Morphological Events Associated with Binary Fission1

Morphogenesis in Conchophthirus curtus has been investigated by the use of protargol silver impregnation supplemented by selective use of scanning electron microscopy. Events are assigned to nine sequential stages; the last, stage 9, which involves maturation of the somatic ciliature and infraciliature as well as the final development of the buccal cavities of both proter and opisthe, occurs following cytokinesis. Stomatogenesis involves both the parental haplokinety and the deep kinetosomal unit (DKU). In perhaps a unique phenomenon, phylogenetically, the ciliated parental haplokinety forms the early oral primordium of the opisthe and is replaced in the proter by the DKU. The DKU then acts as a formative center for new kinetosomes that migrate into the developing opisthe primordium. Late in the process, the haplokinetal primordia of both proter and opisthe give rise to their respective DKU's. Some events of nuclear activity and somatic development are also described. The high degree of structural differentiation of this ciliate has provided the opportunity to examine temporal relationships during morphogenesis. We have found that somatic, buccal, and nuclear events proceed in a tightly coupled sequence. Hence, somatic and nuclear development can be directly correlated with the nine stages of stomatogenesis.     

Morphology,morphogenesis and phylogeny of Anteglaucoma orientalis n. sp. (Ciliophora,Oligohymenophorea), a freshwater hymenostomatid from northeastern China

A new hymenostomatid ciliate, Anteglaucoma orientalis n. sp., isolated from a freshwater pond in Harbin, northeastern China, was investigated using live observation and silver staining methods. Anteglaucoma orientalis is characterized as follows: size in vivo about 50–60 × 30–35 μm; oval body shape; buccal area occupies about 25% of body length; 28–36 somatic kineties; membranelle 1 having six or seven basal body rows, membranelle 2 five to seven rows, and membranelle 3 three rows; single macronucleus with one micronucleus attached. Morphogenesis of the genus Anteglaucoma is revealed for the first time. The main events during binary fission are as follows: morphogenesis begins with proliferation of kinetosomes in the middle part of postoral kinety 1, and kinetosomes of this primordial field multiply and organize to finally form the paroral membrane and membranelles 1–3 of the opisthe; the parental apparatus in the proter does not take part in the stomatogenetic process. Phylogenetic analyses based on SSU rRNA gene sequences show that Anteglaucoma orientalis n. sp. clusters with the type species, A. harbinensis Pan et al., 2017, with full support.     

Description of the Infraciliature and Morphogenesis in the Ciliate Urotricha ondina N. Sp. (Prorodontida, Urotrichidae)

Recent works on prostomatid ciliates show that some genera of this group have a differentiated oral infraciliature and that their stomatogenesis during division involves the proliferation of only a few somatic kineties. These findings have significant implications regarding the iaxonomic status of these genera and also on the terminology used for the oral structures. In Urotricha ondina , the oral infraciliature consists of (1) a paroral kinety formed of paired kinetosomes that encircle the cytostome at the anterior pole of the cell and (2) 3 adoral organelles, each formed of 2 rows of kinetosomes, ventral in position and obliquely disposed, lying above 3 short somatic kineties that do not reach the anterior pole of the cell. This oral ciliature —formerly known as the corona and brosse, respectively—originate during stomatogenesis from the proliferation of 4 somatic kineties that lie posterior to the adoral organelles of the parental cell.     

Dexiotrichides pangi n. sp. (protozoa,ciliophora, scuticociliatia), a new marine ciliate from the north China sea

The morphology, infraciliature, and silverline system of a new marine scuticociliate, Dexiotrichides pangi n. sp. were investigated. The new species is characterized by: size about 45-65 x 20-25 microm in vivo with kidney-like body shape and obliquely truncated semicircle-shaped apical plate; cytostome at bottom of conspicuously depressed oral cavity, which is located at the cell equatorial level; paroral membrane extending anteriorly to membranelle 3; scutica multi-rowed; 33-38 somatic kineties; contractile vacuole near ventral side and subcaudally positioned, opening at posterior end of somatic kinety 3; one oval macronucleus and one small micronucleus; caudal cilium positioned in a small pouch; marine habitat. Based on the data obtained, an improved diagnosis for the genus Dexiotrichides is suggested: body with circular cross-section and conspicuous cilia-free apical plate; buccal cavity conspicuously depressed with cytostome located near or at equatorial level; three membranelles transversely orientated each with 2-3 rows; paroral membrane zigzaging structure, extending to about half of the length of buccal field; multi-rowed scutica; somatic kinety one strongly shortened and terminating anteriorly at posterior end of buccal field; basal bodies in equatorial region arranged usually in circular pattern, while in the anterior portion of somatic kinety 2, basal bodies characteristically in pairs and separated from the posterior part of kinety 2; one caudal cilium.     

Somatic kinetics or paroral membrane: which came first in ciliate evolution?

The ciliate species which lack a distinctive oral ciliature are considered to represent an ancestral state in ciliate evolution. Consequently, the somatic kineties composed of kinetids (kinetosomes plus cilia and associated fibrillar systems) are thought to be the ancestral ciliature. Results on stomatogenesis in 'gymnostomial ciliates' have shown that these ciliates probably have evolved from ancestors already equipped with an oral ciliature. Thus instead of the somatic, the oral ciliature may be regarded an ancestral. Based on these ideas a hypothesis on the evolution of the ciliate kinetome (assembly of all kinetids covering the body of a given ciliate) is presented. The first step in the evolution of the kinetome was the formation of a paroral membrane, a compound ciliary organelle lying along the right side of the oral area which historically but falsely is termed membrane. It was composed of kinetosomal dyads (dikinetids), derived from the kinetid of a dinoflagellate-like ancestor. From the beginning the paroral membrane was responsible for locomotion, ingestion and for the formation of a cytopharyngeal tube which the first ciliate probably had inherited from its flagellate ancestor. In the second step a first somatic kinety was formed from the right row of kinetosomes of the paroral membrane as a result of a longitudinal splitting of the paroral membrane and a subsequent migration of the forming kinety to the right into the somatic cortex. To increase the number of somatic kineties this process was repeated until the kinety produced first reached the left border of the oral area. By this step the locomotive and the nutritional functions were differentiated between somatic and oral structures. In a third step the adoral organelles were formed from somatic kinetids left of the oral area. The primitive type of stomatogenesis was a buccokinetal one derived from the mode the flagellate ancestor used to distribute its replicated kinetosomes to the offspring cells (buccokinetal means that at least parts of the oral anlage for the posterior offspring cell has its origin in the parental oral apparatus). This hypothesis, based on comparative studies on ciliate morphogenesis, is corroborated by molecular data from other laboratories.     

The Cortical Morphogenetic Cycle Associated with Cell Division in Diophrys Dujardin, 1841 (Ciliophora,Hypotrichida)1

Morphogenesis of cell division was investigated in Diophrys scutum, D. oligothrix, and D. appendiculata utilizing both light microscopy of living and stained specimens and SEM of preserved specimens. The cortical morphogenetic pattern of Diophrys is similar to that of other members of the family Euplotidae. The opisthe oral primordium, which develops in a subsurface pouch, forms posterior to the parental buccal cavity. The proter inherits the parental adoral zone of membranelles (AZM) apparently unchanged. The endoral membrane forms to the right of the posterior end of the AZM in the proter, in association with the developing AZM in the opisthe. The paroral cirrus and membrane develop from a single streak that first appears along the right edge of the buccal cavity in the proter to the right of the developing buccal structures of the opisthe. Frontal and transverse cirri develop in both proter and opisthe from five separate cirral primordia that form to the right of the buccal cavity. Left marginal cirri do not develop in association with the corresponding parental structures. Kinetosomes formed within the opisthe oral primordium, or kinetosomes that were part of any parental ciliary structure, do not appear to become part of any developing paroral structures, frontal, transverse, or left marginal cirri. Speciation within the genus Diophrys and evolution of the family Euplotidae as they relate to the morphogenesis of cortical structure are discussed.