冠突伪尾柱虫小核对胞口结构稳定性的影响  

MICRONUCLEAR EFFECT ON STRUCTURAL STABILITY OF THE ORAL APPARATUS IN HYPOTRICHOUS CILIATE (PSEUDOUROSTYLA CRISTATA)

作　　者：金立培[1] 金华中[1] 

机构地区：[1]中山大学生命科学学院,广州510275

出　　处：《动物学报》2002年第2期258-263,共6页ACTA ZOOLOGICA SINICA

基　　金：国家自然科学基金项目 (No 39970 0 89)~~

摘　　要：在通过显微手术所建立的冠突伪尾柱虫 (Pseudourostylacristata)无小核系中 ,部分细胞因口围带翻领部小膜出现不同程度的缺损而导致畸形 ;在细胞生长静止期的群体中 ,口围带畸形率高达 5 0 %以上 ;对无小核系 6 0 0多个刚完成二分裂的前、后仔虫及 10 0 0多个生理改组末期的虫体进行蛋白银染色观察 ,除发现 4个二分裂仔虫和 3个生理改组后虫体的口围带异常外 ,绝大多数经过形态发生后的细胞都具有正常的胞口结构。另一方面 ,选择性培养实验进一步证明 ,口围带畸型产生于非形态发生期。由此可见 ,失去小核的细胞 ,同时也失去了胞口结构的稳定性。To explore the generality of the morphogenetic function of the micronucleus among ciliates, we employed five stocks of hypotrichous ciliate Pseudourostyla cristata : 2, 4, 6, 28 and 46, and five amicronucleate cell lines:2aml, 4aml, 6aml, 28aml and 46aml derived from stocks 2, 4, 6, 28 and 46 respectively, which were generated by amputation of the cell when the micronuclei became aligned on the left side of the amalgamated macronuclei during cell division. Micronucleate cell lines 2ml, 4ml, 28ml and 46ml derived after amputation but retaining the micronuclei were also studied and served as controls. For observation of the cortex and nuclei, protargol staining was used throughout. The evident character of the amicronucleate cell lines, as compared with the normal and the micronucleate cell lines, was that a substantial proportion of cells exhibited an abnormal adoral zone of membranelles (AZM). When the culture medium began to age after 7～10 days, the culture soon entered stationary phase of growth. During the period abnormal AZMs were observed in over 50% of amicronucleate cells in various cell lines, among which the percentage of 6aml cells with defective AZM came up to 98%. In fact, the percentage of cells with abnormal AZM in a culture population was changeable and varied from low to high from exponential growth phase to stationary phase. These abnormal patterns involved various degrees of reduction of membranellar width in the anterior and middle part of the AZM lapel (AZM L), and in severe cases disruption of AZM continuity due to the loss of some membranelles, and also indentation of the cytoplasm in this region. Morphogenesis of the amicronucleates in binary fission and in physiological reorganization was observed. Restructuring of the pre existing oral apparatus, both during binary fission in the putative proter and during physiological reorganization, resulted in the formation of a normal AZM. After restoration of normal AZM in binary fission or physiological reorganization, abnormal AZM pat

关 键 词：小核对 胞口结构 稳定性 腹毛类纤毛虫 冠突伪尾柱虫 无性分裂 口器发生 

分 类 号：Q959.117[生物学—动物学]