We examined the structure and spatial organization of ciliature base-associated microtubules （BAM） in three hypotrichous ciliates （Stylonychia mytilus, Pseudourostyla cristata, Euplotes woodruffi） in fluorescence ...We examined the structure and spatial organization of ciliature base-associated microtubules （BAM） in three hypotrichous ciliates （Stylonychia mytilus, Pseudourostyla cristata, Euplotes woodruffi） in fluorescence microscopy. The results revealed that BAM, including the anterior （ALM）, posterior longitudinal microtubule （PLM） and the transverse microtubule （TM） bands, are composed of tubulin. The respective microtubular bands have cytoplasmic polarization patterns that are significantly asymmetric. The BAM of the midventral files in P. cristata appear cord-shaped compared with the ALM bands of transverse cirri in both S. mytilus and E. woodruffi, which extend to the left anterior side of the cell before converging. The TM bands of the left marginal cirri （MC） in S. rnytilus extend to the right side of the cell, while those of the right MC bands extend to the left. Our observations suggest that BAM traits are common in hypotrichous ciliates even though different species possess different microtubule arrangements related to the conserved cirral morphogenetic patterns in the respective species. The differing development of BAM in the three ciliate suggests that the microtubules may be conserved in different hypotrichs. We have also demonstrated that the BAM, which appear polar and asymmetric, are localized in specific cytoskeletal positions and extend in different orientations within the cortex to connect with other ciliature-associated structures and, thus, strengthen the cortex. These BAM features indicate that they are directly associated with cell motion.展开更多
We reinvestigate the morphology of two oligotrich and two hypotrich ciliates collected from the coasts of north and south China,viz.,Parallelostrombidium obesum Liu et al.,2015,Spirostrombidium apourceolare Liu et al....We reinvestigate the morphology of two oligotrich and two hypotrich ciliates collected from the coasts of north and south China,viz.,Parallelostrombidium obesum Liu et al.,2015,Spirostrombidium apourceolare Liu et al.,2013,Protogastrostyla pulchra(Pereyaslawzewa,1886)Gong et al.,2007,and Uncinata bradburyae(Gong et al.,2001)Luo et al.,2015.All the populations match well with the original samples identified in previous studies.Supplemental taxonomic data were supplied for these four species of the new populations.The species Parallelostrombidium obesum is characterised by its dorsal-ventrally flattened body shape with anterior and posterior ends transversely truncating,as well as two thigmotactic membranelles and girdle kinety that spirals around the cell one and a half times.Spirostrombidium apourceolare is characterised by its elongate ellipsoidal and dorsal-ventrally flattened body shape,two thigmotactic membranelles,about 11-27 ovoid macronuclear nodules,and girdle kinety that spirals around the cell twice with two undulations.Protogastrostyla pulchra is characterised by its elongate body shape and unique,caudally located food vacuole.Based on the new populations,we described the smaller cortical granules,clustered around dorsal bristles for the first time.The new population of Uncinata bradburyae shares the diagnostic features with the type population,which include prominent beak-like projection in anterior region,the conspicuous gap of adoral zone,proximalmost adoral membranelles distinctly elongated,and infraciliature.展开更多
The cortical development and macronuclear evolution of the marine hypotrichous ciliate Anteholosticha manca, collected from the coastal waters near Qingdao, China, were investigated using the protargol impregnation me...The cortical development and macronuclear evolution of the marine hypotrichous ciliate Anteholosticha manca, collected from the coastal waters near Qingdao, China, were investigated using the protargol impregnation method. The morphogenesis of A. manca is generally typical for the genus, and can be characterized as the following features ： （ 1 ） in the proter, a new oral primordium is formed on the bottom （beneath the pellicle） of the buccal cavity, disorganization of the parental undulating membranes do not contribute to the formation of this primordium ; （2） FVT-cirral anlagen in both dividers develop independently, and very likely only a few midventral cirri join in the formation of these primordia; （ 3 ） both marginal row and dorsal kinety anlagen develop intrakinetally within the parental structure; （4） at the middle stage, macronuclear segments fuse together to form a single mass as observed in most of its related forms.展开更多
Morphogenesis of a population of the marine euplotid ciliate,Uronychia binucleata,which was found in Yellow Sea coastal waters next to a sewage outfall at a beach near Zhanqiao Pier,Qingdao,China,was investigated usin...Morphogenesis of a population of the marine euplotid ciliate,Uronychia binucleata,which was found in Yellow Sea coastal waters next to a sewage outfall at a beach near Zhanqiao Pier,Qingdao,China,was investigated using protargol staining.The main pattern of morphogenesis is typical for the genus and can be summarized as follows:1)the oral primordium in both proter and opisthe develops de novo in a subcortical pouch.In each daughter cell,the developing adoral zone of membranelles divides into two parts.The new membranelles formed in the proter's oral primordium will replace the leftmost five parental ones;six parental membranelles are retained by the proter;2)the undulating membranes anlage is formed and develops independently from the oral primordium within the same subcortical pouch;3)five primary front oventral-transverse cirral anlagen appear de novo on the cell surface;4)the marginal cirral anlagen are formed de novo;5)the leftmost frontal cirrus develops de novo on the cell surface;6)two caudal cirri are formed at the posterior end of the rightmost anlage while the second primordium from the right gives rise to the third caudal cirrus.In contrast to its congeners,the anlage of the leftmost frontal cirrus is formed to the right of the undulating membranes anlage and before the formation of the latter.展开更多
In sharp contrast to their pelagic relatives,the oligotrichs,the overwhelming majority of hypotrich ciliates inhabit the benthos.Only a few species,including those of the genus Hypotrichidium Ilowaisky,1921,have adapt...In sharp contrast to their pelagic relatives,the oligotrichs,the overwhelming majority of hypotrich ciliates inhabit the benthos.Only a few species,including those of the genus Hypotrichidium Ilowaisky,1921,have adapted to a planktonic lifestyle.The ontogenetic mode of the highly differentiated ciliate,Hypotrichidium tisiae(Gelei,1929)Gelei,1954,is unknown.In this study,the interphase morphology and the ontogenetic process of this species are investigated.Accordingly,the previously unidentified ciliary pattern of Hypotrichidium is redefined.The main morphogenetic features are as follows:(1)The parental adoral zone of membranelles is inherited completely by the proter and the oral primordium of the opisthe arises in a deep pouch.(2)Five frontoventral cirral anlagen(FVA)are formed:FVA I contributes to the single frontal cirrus,FVA II–IV generate three frontoventral cirral rows,FVA V migrates and forms postoral ventral cirri.(3)All marginal cirral row anlagen develop de novo:each of the two left anlagen forms a single cirral row,while the single right anlage fragments into anterior and posterior parts.(4)Two dorsal kinety anlagen occur de novo,with the right one fragmenting to form kineties 2 and 3.(5)Two long caudal cirral rows are formed at the ends of dorsal kineties 1 and 3.On the basis of the morphogenetic features and phylogenetic analyses,the assignment of Hypotrichidium to the family Spirofilidae Gelei,1929 within Postoralida is supported.The establishment of separate families for the slender“tubicolous”spirofilids and the highly helical spirofilids is also validated.展开更多
基金Supported by the National Natural Science Foundation of China (No. 30770238)
文摘We examined the structure and spatial organization of ciliature base-associated microtubules （BAM） in three hypotrichous ciliates （Stylonychia mytilus, Pseudourostyla cristata, Euplotes woodruffi） in fluorescence microscopy. The results revealed that BAM, including the anterior （ALM）, posterior longitudinal microtubule （PLM） and the transverse microtubule （TM） bands, are composed of tubulin. The respective microtubular bands have cytoplasmic polarization patterns that are significantly asymmetric. The BAM of the midventral files in P. cristata appear cord-shaped compared with the ALM bands of transverse cirri in both S. mytilus and E. woodruffi, which extend to the left anterior side of the cell before converging. The TM bands of the left marginal cirri （MC） in S. rnytilus extend to the right side of the cell, while those of the right MC bands extend to the left. Our observations suggest that BAM traits are common in hypotrichous ciliates even though different species possess different microtubule arrangements related to the conserved cirral morphogenetic patterns in the respective species. The differing development of BAM in the three ciliate suggests that the microtubules may be conserved in different hypotrichs. We have also demonstrated that the BAM, which appear polar and asymmetric, are localized in specific cytoskeletal positions and extend in different orientations within the cortex to connect with other ciliature-associated structures and, thus, strengthen the cortex. These BAM features indicate that they are directly associated with cell motion.
基金supported by the National Natural Science Foundation of China(Nos.31801955,31702009)the China Postdoctoral Science Foundation(Nos.2017M622276,BX20180348)
文摘We reinvestigate the morphology of two oligotrich and two hypotrich ciliates collected from the coasts of north and south China,viz.,Parallelostrombidium obesum Liu et al.,2015,Spirostrombidium apourceolare Liu et al.,2013,Protogastrostyla pulchra(Pereyaslawzewa,1886)Gong et al.,2007,and Uncinata bradburyae(Gong et al.,2001)Luo et al.,2015.All the populations match well with the original samples identified in previous studies.Supplemental taxonomic data were supplied for these four species of the new populations.The species Parallelostrombidium obesum is characterised by its dorsal-ventrally flattened body shape with anterior and posterior ends transversely truncating,as well as two thigmotactic membranelles and girdle kinety that spirals around the cell one and a half times.Spirostrombidium apourceolare is characterised by its elongate ellipsoidal and dorsal-ventrally flattened body shape,two thigmotactic membranelles,about 11-27 ovoid macronuclear nodules,and girdle kinety that spirals around the cell twice with two undulations.Protogastrostyla pulchra is characterised by its elongate body shape and unique,caudally located food vacuole.Based on the new populations,we described the smaller cortical granules,clustered around dorsal bristles for the first time.The new population of Uncinata bradburyae shares the diagnostic features with the type population,which include prominent beak-like projection in anterior region,the conspicuous gap of adoral zone,proximalmost adoral membranelles distinctly elongated,and infraciliature.
基金The National Natural Science Foundation of China under contract Nos30570236 and 30430090the Darwin Initiative Programme of UKunder contract No 14-015the Center of Excellence in Biodiversity,King Saud University,Saudi Arabia
文摘The cortical development and macronuclear evolution of the marine hypotrichous ciliate Anteholosticha manca, collected from the coastal waters near Qingdao, China, were investigated using the protargol impregnation method. The morphogenesis of A. manca is generally typical for the genus, and can be characterized as the following features ： （ 1 ） in the proter, a new oral primordium is formed on the bottom （beneath the pellicle） of the buccal cavity, disorganization of the parental undulating membranes do not contribute to the formation of this primordium ; （2） FVT-cirral anlagen in both dividers develop independently, and very likely only a few midventral cirri join in the formation of these primordia; （ 3 ） both marginal row and dorsal kinety anlagen develop intrakinetally within the parental structure; （4） at the middle stage, macronuclear segments fuse together to form a single mass as observed in most of its related forms.
基金supported by the National Natural Science Foundation of China(Nos.31872190,31702009)the Key Laboratory of Mariculture(KLM),Ministry of Education,Ocean University of China(OUC)the Innovation Team of Team of Higher Learning Insritutions of Tianjin(No.TD13-5089)
文摘Morphogenesis of a population of the marine euplotid ciliate,Uronychia binucleata,which was found in Yellow Sea coastal waters next to a sewage outfall at a beach near Zhanqiao Pier,Qingdao,China,was investigated using protargol staining.The main pattern of morphogenesis is typical for the genus and can be summarized as follows:1)the oral primordium in both proter and opisthe develops de novo in a subcortical pouch.In each daughter cell,the developing adoral zone of membranelles divides into two parts.The new membranelles formed in the proter's oral primordium will replace the leftmost five parental ones;six parental membranelles are retained by the proter;2)the undulating membranes anlage is formed and develops independently from the oral primordium within the same subcortical pouch;3)five primary front oventral-transverse cirral anlagen appear de novo on the cell surface;4)the marginal cirral anlagen are formed de novo;5)the leftmost frontal cirrus develops de novo on the cell surface;6)two caudal cirri are formed at the posterior end of the rightmost anlage while the second primordium from the right gives rise to the third caudal cirrus.In contrast to its congeners,the anlage of the leftmost frontal cirrus is formed to the right of the undulating membranes anlage and before the formation of the latter.
基金supported by the National Natural Science Foundation of China(Nos.31900319,32030015,32070432)the National Key Research and Development Program of China(No.2018YFD0900701)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2019333).
文摘In sharp contrast to their pelagic relatives,the oligotrichs,the overwhelming majority of hypotrich ciliates inhabit the benthos.Only a few species,including those of the genus Hypotrichidium Ilowaisky,1921,have adapted to a planktonic lifestyle.The ontogenetic mode of the highly differentiated ciliate,Hypotrichidium tisiae(Gelei,1929)Gelei,1954,is unknown.In this study,the interphase morphology and the ontogenetic process of this species are investigated.Accordingly,the previously unidentified ciliary pattern of Hypotrichidium is redefined.The main morphogenetic features are as follows:(1)The parental adoral zone of membranelles is inherited completely by the proter and the oral primordium of the opisthe arises in a deep pouch.(2)Five frontoventral cirral anlagen(FVA)are formed:FVA I contributes to the single frontal cirrus,FVA II–IV generate three frontoventral cirral rows,FVA V migrates and forms postoral ventral cirri.(3)All marginal cirral row anlagen develop de novo:each of the two left anlagen forms a single cirral row,while the single right anlage fragments into anterior and posterior parts.(4)Two dorsal kinety anlagen occur de novo,with the right one fragmenting to form kineties 2 and 3.(5)Two long caudal cirral rows are formed at the ends of dorsal kineties 1 and 3.On the basis of the morphogenetic features and phylogenetic analyses,the assignment of Hypotrichidium to the family Spirofilidae Gelei,1929 within Postoralida is supported.The establishment of separate families for the slender“tubicolous”spirofilids and the highly helical spirofilids is also validated.
