摘要
采用扫描电镜、透射电镜和蛋白银染色等方法研究了海蜇胚胎发育和变态过程中细胞超微结构变化。结果显示:(1)海蜇自受精卵至原肠期阶段细胞均等分裂,细胞间存在大量连接,细胞形态相近,未出现显著分化;(2)海蜇自早期浮浪游虫阶段,其外胚层细胞开始出现空泡化,至4触手螅状体阶段外胚层细胞空泡体积逐渐增大,而内胚层细胞仅在4触手螅状体阶段才出现空泡化。伴随着外胚层细胞空泡化比例的增大,杯状体和4触手螅状体阶段出现疑似凋亡小体结构;(3)刺细胞分化于早期浮浪游虫期的外胚层近中胶层区域,而后逐渐向外转移,至4触手螅状体阶段发育成熟并转移至表面;(4)纤毛形成于早期浮浪幼虫,在杯状体阶段逐渐退化,并于4触手螅状体阶段完全消失;(5)在海蜇早期发育各个阶段,其内部均发现大量着色较深的卵黄体,且在浮浪游虫阶段首次发现了海蜇外层细胞主动吞噬细菌现象,表明海蜇早期发育营养来自内源性和外源性两部分。研究结果可为阐明刺胞动物早期发育模式提供依据。
This study investigated cell ultrastructure of Rhopilema esculentum during embryogesis and metamorphosis into a polyp using scanning and transmission electron microscopy combined with protargol staining method.Our study showed that(1)Cell cleavage was almost equal from fertilized egg to gastrula.All divided cells were similar in morphology,and cell junctions were observed among adjacent cells;(2)Vacuoles in cell were firstly observed at ectoderm of early planula,and became bigger as developing to 4-tentacle polyp,while the vacuoles of entoderm were firstly found at 4-tentacle polyp stage.The suspected apoptotic body were observed at scyphostoma and polyp stages;(3)Immature cnidocytes were firstly observed in ectodermal area closed to mesoglea ectoderm at early planula stage,moved to outside,located at outermost layer,and matured at polyp stage;(4)Cilium was observed at early planula stage,gradually degraded,and completely disappeared at polyp stage;(5)Lots of yolk bodies with dark stain were observed at all developmental stages,and the phagocytosis of ectodermal cell of planula was firstly observed.These phenomena suggest that planulae of R.esculentum were both planktotrophic and lecithotrophic,which would provide the scientific basis for illuminating the developmental pattern of embryonic and metamorphosis of cnidarians.
作者
刘春胜
万逸
高菲
陈四清
王爱民
顾志峰
LIU Chun-Sheng;WAN Yi;GAO Fei;CHEN Si-Qing;WANG Ai-Ming;GU Zhi-Feng(State Key Laboratory of Marine Resource Utilization in South China Sea,Hainan University,Haikou 570228,China;The Ocean College,Hainan University,Haikou 570228,China;Yellow Sea Fisheries Research Institute Chinese Academy of Fishery Sciences,Qingdao 266071,China)
出处
《水生生物学报》
CAS
CSCD
北大核心
2018年第5期1019-1026,共8页
Acta Hydrobiologica Sinica
基金
北方海水增养殖重点实验室开放课题(2014-MSENC-KF-01)
海南大学科研团队培育专项(HDKYTG201704)
海南省自然科学基金项目(317029)资助~~
关键词
海蜇
胚胎发育
变态
细胞超微结构
发育模式
Rhopilema esculentum
Embryonic development
Metamorphosis
Cell ultrastructure
Developmental pattern
