Functional and phylogenetic aspects of the ciliary membrane: A comparative freeze-fracture study

Bardele, Christian F.

doi:10.1016/0303-2647(81)90046-0

Cited by 75 publications

(33 citation statements)

References 24 publications

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“…Therefore, the relationships among the subclasses are not clearly resolved. The previously suggested close relationship between peritrichs and scuticociliates} based on the ciliary membrane (Bardele 1981), and the close relationship between peritrichs and peniculines (Greenwood et al 1991; Miao et al 2001) were not supported by our data as peritrichs and hymenostomes formed a well‐supported clade (77% NJ, 69% ML, 77% MP).…”

Section: Discussioncontrasting

confidence: 86%

Phylogenetic Relationships of the Subclass Peritrichia (Oligohymenophorea, Ciliophora) Inferred from Small Subunit rRNA Gene Sequences¹

Miao

Fen

et al. 2004

J Eukaryotic Microbiology

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The phylogenetic relationships among peritrichs remain unresolved. In this study, the complete small subunit rRNA (SSrRNA) gene sequences of seven species (Epistylis galea, Campanella umbellaria, Carchesium polypinum, Zoothamnium arbuscula, Vaginicola crystallina, Ophrydium versatile, and Opercularia microdiscum) were determined. Trees were constructed using distance-matrix, maximum-likelihood and maximum-parsimony methods, all of which strongly supported the monophyly of the subclass Peritrichia. Within the peritrichs, 1) E. galea grouped with Opercularia microdiscum and Campanella umbellaria but not the other Epistylis species, which indicates that the genus Epistylis might not be monophyletic; 2) the topological position of Carchesium and Campanella suggested that Carchesium should be placed in the family Zoothamniidae, or be elevated to a higher taxonomic rank, and that Campanella should be independent of the family Epistylididae, and probably be given a new rank; and 3) Opisthonecta grouped strongly with Astylozoon, which suggested that Opisthonecta species were not the ancestors of the stalked peritrichs.

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Section: Discussioncontrasting

confidence: 86%

Phylogenetic Relationships of the Subclass Peritrichia (Oligohymenophorea, Ciliophora) Inferred from Small Subunit rRNA Gene Sequences¹

Miao

Fen

et al. 2004

J Eukaryotic Microbiology

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“…Within the Class Oligohymenophorea, the Subclasses Scuticociliatia and Hymenostomatia are likely sister taxa. This was suggested earlier (Bardele 1981; Beran 1990; Lynn 1979, 1981), based on ultrastructure, particularly the radially‐oriented transverse ribbons of the somatic kinetids. The Subclasses Peniculia, Scuticociliatia, and Peritrichia can be related on basic similarities in their buccokinetal stomatogenesis.…”

Section: Discussionsupporting

confidence: 54%

Phylogenetic Relationships of the Subclass Peniculia (Oligohymenophorea, Ciliophora) Inferred from Small Subunit rRNA Gene Sequences

Strüder‐Kypke

Wright

Fokin

et al. 2000

J Eukaryotic Microbiology

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Peniculine ciliates have been recognized as a distinct higher taxon of ciliates for almost 50 years. However, phylogenetic relationships within the Subclass Peniculia are still unsettled. To contribute to our understanding of their phylogeny and provide evidence for the position of Urocentrum turbo, we sequenced its small subunit (SS) rRNA gene and the SSrRNA genes from Lembadion bullinum, Frontonia sp., Paramecium caudatum, Paramecium multimicronucleatum, Paramecium putrinum, and Paramecium woodruffi. Urocentrum turbo was the only one of these species not to exhibit a shortened Helix E10_1, which we conclude characterizes the "higher" peniculines. Except for U. turbo, the peniculines are strongly supported as a monophyletic clade with Lembadion, Frontonia, and Paramecium species forming separate and strongly supported clades by bootstrap analysis using distance matrix, maximum parsimony, and maximum likelihood methods. Urocentrum turbo is associated with different lineages, depending upon the analysis used. The Paramecium species form at least four clades with the Paramecium aurelia subgroup being the most derived. We conclude that the Subclass Peniculia should be divided into two orders, the Order Urocentrida and Order Peniculida, with the latter order having two suborders, the Suborder Frontoniina and Peniculina. We place U. turbo with the peniculines because of shared morphological and stomatogenetic features.

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“…5B); these we interpret as the flagellar plaques (27). The corresponding E-face views were devoid of detectable IMP organization.…”

Section: The Distribution Of Intramembrane Particles (Imps) Within Thmentioning

confidence: 86%

Membrane domains and flagellar pocket boundaries are influenced by the cytoskeleton in African trypanosomes

Gadelha

Rothery

Morphew

et al. 2009

Proc. Natl. Acad. Sci. U.S.A.

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A key feature of immune evasion for African trypanosomes is the functional specialization of their surface membrane in an invagination known as the flagellar pocket (FP), the cell's sole site of endocytosis and exocytosis. The FP membrane is biochemically distinct yet continuous with those of the cell body and the flagellum. The structural features maintaining this individuality are not known, and we lack a clear understanding of how extracellular components gain access to the FP. Here, we have defined domains and boundaries on these surface membranes and identified their association with internal cytoskeletal features. The FP membrane appears largely homogeneous and uniformly involved in endocytosis. However, when endocytosis is blocked, receptor-mediated and fluid-phase endocytic markers accumulate specifically on membrane associated with four specialized microtubules in the FP region. These microtubules traverse a distinct boundary and associate with a channel that connects the FP lumen to the extracellular space, suggesting that the channel is the major transport route into the FP.electron tomography ͉ endocytosis ͉ freeze fracture ͉ Trypanosoma brucei ͉ flagellum P arasitic protozoa, like many cells, organize their surface membranes into subdomains or microenvironments that are specialized to accomplish particular recognition, secretory, and endocytic functions. The surfaces of parasitic organisms, however, have an extra level of constraint; they must perform these vital roles while the organism avoids elimination by defensive responses mounted by the host.The compartmentalization of surface membrane is especially interesting in African trypanosomes because of their particular parasitic lifestyle. Trypanosoma brucei is a flagellate protozoan that lives in the blood of mammals in an exclusively extracellular form, fully exposed to the host immune system. Survival is assisted both by rapid endocytosis that clears the entire cell surface of bound antibodies within Ϸ7 min (1) and through the expression of a series of immunologically distinct cell surface coats. Each coat is produced from a single GPI-anchored variant surface glycoprotein (VSG; ref.2). Periodic switching of the expressed VSG gene from a vast silent library enables the parasite to avoid clearance by the host's adaptive immune response, hence prolonging infection and increasing the chances of transmission by the bite of a tsetse fly.African trypanosomes maintain the VSG coat free of most invariant endocytosis receptors that could otherwise elicit an immune response from which the organism could not escape. This is achieved through specialization of the plasma membrane at the base of the flagellum to create a protected invagination, the flagellar pocket (FP), in which the invariant receptors for endocytosis and innate immune evasion are concentrated (3, 4). The FP is the sole site for all endocytosis and exocytosis, and along with this critical function, it also plays important roles in protein and lipid sorting and recycling (for review, see ref. ...

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Functional and phylogenetic aspects of the ciliary membrane: A comparative freeze-fracture study

Cited by 75 publications

References 24 publications

Phylogenetic Relationships of the Subclass Peritrichia (Oligohymenophorea, Ciliophora) Inferred from Small Subunit rRNA Gene Sequences¹

Phylogenetic Relationships of the Subclass Peritrichia (Oligohymenophorea, Ciliophora) Inferred from Small Subunit rRNA Gene Sequences¹

Phylogenetic Relationships of the Subclass Peniculia (Oligohymenophorea, Ciliophora) Inferred from Small Subunit rRNA Gene Sequences

Membrane domains and flagellar pocket boundaries are influenced by the cytoskeleton in African trypanosomes

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Functional and phylogenetic aspects of the ciliary membrane: A comparative freeze-fracture study

Cited by 75 publications

References 24 publications

Phylogenetic Relationships of the Subclass Peritrichia (Oligohymenophorea, Ciliophora) Inferred from Small Subunit rRNA Gene Sequences1

Phylogenetic Relationships of the Subclass Peritrichia (Oligohymenophorea, Ciliophora) Inferred from Small Subunit rRNA Gene Sequences1

Phylogenetic Relationships of the Subclass Peniculia (Oligohymenophorea, Ciliophora) Inferred from Small Subunit rRNA Gene Sequences

Membrane domains and flagellar pocket boundaries are influenced by the cytoskeleton in African trypanosomes

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Product

Resources

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Phylogenetic Relationships of the Subclass Peritrichia (Oligohymenophorea, Ciliophora) Inferred from Small Subunit rRNA Gene Sequences¹

Phylogenetic Relationships of the Subclass Peritrichia (Oligohymenophorea, Ciliophora) Inferred from Small Subunit rRNA Gene Sequences¹