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Flagellar morphology

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https://www.readbyqxmd.com/read/29772025/shape-shifting-trypanosomes-flagellar-shortening-followed-by-asymmetric-division-in-trypanosoma-congolense-from-the-tsetse-proventriculus
#1
Lori Peacock, Christopher Kay, Mick Bailey, Wendy Gibson
Trypanosomatids such as Leishmania and Trypanosoma are digenetic, single-celled, parasitic flagellates that undergo complex life cycles involving morphological and metabolic changes to fit them for survival in different environments within their mammalian and insect hosts. According to current consensus, asymmetric division enables trypanosomatids to achieve the major morphological rearrangements associated with transition between developmental stages. Contrary to this view, here we show that the African trypanosome Trypanosoma congolense, an important livestock pathogen, undergoes extensive cell remodelling, involving shortening of the cell body and flagellum, during its transition from free-swimming proventricular forms to attached epimastigotes in vitro...
May 2018: PLoS Pathogens
https://www.readbyqxmd.com/read/29765641/combined-morphological-and-phylogenomic-re-examination-of-malawimonads-a-critical-taxon-for-inferring-the-evolutionary-history-of-eukaryotes
#2
Aaron A Heiss, Martin Kolisko, Fleming Ekelund, Matthew W Brown, Andrew J Roger, Alastair G B Simpson
Modern syntheses of eukaryote diversity assign almost all taxa to one of three groups: Amorphea, Diaphoretickes and Excavata (comprising Discoba and Metamonada). The most glaring exception is Malawimonadidae, a group of small heterotrophic flagellates that resemble Excavata by morphology, but branch with Amorphea in most phylogenomic analyses. However, just one malawimonad, Malawimonas jakobiformis , has been studied with both morphological and molecular-phylogenetic approaches, raising the spectre of interpretation errors and phylogenetic artefacts from low taxon sampling...
April 2018: Royal Society Open Science
https://www.readbyqxmd.com/read/29622088/re-description-of-the-sperm-morphology-of-dalbulus-maidis-hemiptera-cicadellidae-deltocephalinae
#3
Marcelo Silva Barcellos, Glenda Dias, José Lino-Neto
The corn leafhopper, Dalbulus maidis, which is one of the most important vectors of maize diseases, had the morphology of its spermatozoa described more than 40 years ago. However, the description is imprecise, requiring certain rectifications. Hence, we re-describe the sperm morphology of this species using light microscopy and transmission electron microscopy. Their spermatozoa measured from 118.1 to 128.5 μm in length, this value being about three times smaller than what was previously described. The head region is formed by a small acrosome and the nucleus...
April 2018: Tissue & Cell
https://www.readbyqxmd.com/read/29610725/guidance-and-self-sorting-of-active-swimmers-3d-periodic-arrays-increase-persistence-length-of-human-sperm-selecting-for-the-fittest
#4
Thiruppathiraja Chinnasamy, James L Kingsley, Fatih Inci, Paul J Turek, Mitchell P Rosen, Barry Behr, Erkan Tüzel, Utkan Demirci
Male infertility is a reproductive disease, and existing clinical solutions for this condition often involve long and cumbersome sperm sorting methods, including preprocessing and centrifugation-based steps. These methods also fall short when sorting for sperm free of reactive oxygen species, DNA damage, and epigenetic aberrations. Although several microfluidic platforms exist, they suffer from structural complexities, i.e., pumps or chemoattractants, setting insurmountable barriers to clinical adoption. Inspired by the natural filter-like capabilities of the female reproductive tract for sperm selection, a model-driven design, featuring pillar arrays that efficiently and noninvasively isolate highly motile and morphologically normal sperm, with lower epigenetic global methylation, from raw semen, is presented...
February 2018: Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
https://www.readbyqxmd.com/read/29606301/absence-of-cfap69-causes-male-infertility-due-to-multiple-morphological-abnormalities-of-the-flagella-in-human-and-mouse
#5
Frederick N Dong, Amir Amiri-Yekta, Guillaume Martinez, Antoine Saut, Julie Tek, Laurence Stouvenel, Patrick Lorès, Thomas Karaouzène, Nicolas Thierry-Mieg, Véronique Satre, Sophie Brouillet, Abbas Daneshipour, Seyedeh Hanieh Hosseini, Mélanie Bonhivers, Hamid Gourabi, Emmanuel Dulioust, Christophe Arnoult, Aminata Touré, Pierre F Ray, Haiqing Zhao, Charles Coutton
The multiple morphological abnormalities of the flagella (MMAF) phenotype is among the most severe forms of sperm defects responsible for male infertility. The phenotype is characterized by the presence in the ejaculate of immotile spermatozoa with severe flagellar abnormalities including flagella being short, coiled, absent, and of irregular caliber. Recent studies have demonstrated that MMAF is genetically heterogeneous, and genes thus far associated with MMAF account for only one-third of cases. Here we report the identification of homozygous truncating mutations (one stop-gain and one splicing variant) in CFAP69 of two unrelated individuals by whole-exome sequencing of a cohort of 78 infertile men with MMAF...
March 28, 2018: American Journal of Human Genetics
https://www.readbyqxmd.com/read/29604574/phylogeny-and-morphology-of-new-diplonemids-from-japan
#6
Daria Tashyreva, Galina Prokopchuk, Akinori Yabuki, Binnypreet Kaur, Drahomíra Faktorová, Jan Votýpka, Chiho Kusaka, Katsunori Fujikura, Takashi Shiratori, Ken-Ichiro Ishida, Aleš Horák, Julius Lukeš
Diplonemids were recently found to be the most species-rich group of marine planktonic protists. Based on phylogenetic analysis of 18S rRNA gene sequences and morphological observations, we report the description of new members of the genus Rhynchopus - R. humris sp. n. and R. serpens sp. n., and the establishment of two new genera - Lacrimia gen. n. and Sulcionema gen. n., represented by L. lanifica sp. n. and S. specki sp. n., respectively. In addition, we describe the organism formerly designated as Diplonema sp...
February 21, 2018: Protist
https://www.readbyqxmd.com/read/29595414/the-flag-regulator-is-involved-in-length-control-of-the-polar-flagella-of-campylobacter-jejuni
#7
Tomoharu Inoue, Clive S Barker, Hideyuki Matsunami, Shin-Ichi Aizawa, Fadel A Samatey
Campylobacter jejuni cells have bipolar flagella. Both flagella have similar lengths of about one helical turn, or 3.53±0.52 µm. The flagellar filament is composed of two homologous flagellins: FlaA and FlaB. Mutant strains that express either FlaA or FlaB alone produce filaments that are shorter than those of the wild-type. It is reported that the flaG gene could affect filament length in some species of bacteria, but its function remains unknown. We introduced a flaG-deletion mutation into the C. jejuni wild-type strain and flaA- or flaB-deletion mutant strains, and observed their flagella by microscopy...
March 29, 2018: Microbiology
https://www.readbyqxmd.com/read/29511984/analysis-of-the-function-of-kif3a-and-kif3b-in-the-spermatogenesis-in-boleophthalmus-pectinirostris
#8
Yong-Qiang Zhao, Dan-Li Mu, Di Wang, Ying-Li Han, Cong-Cong Hou, Jun-Quan Zhu
Spermatogenesis represents one of the most complicated morphological transformation procedures. During this process, the assembly and maintenance of the flagella and intracellular transport of membrane-bound organelles required KIF3A and KIF3B. Our main goal was to test KIF3A and KIF3B location during spermatogenesis of Boleophthalmus pectinirostris. We cloned complete cDNA of KIF3A/3B from the testis of B. pectinirostris by PCR and rapid amplification of cDNA ends (RACE). The predicted secondary and tertiary structures of B...
June 2018: Fish Physiology and Biochemistry
https://www.readbyqxmd.com/read/29511084/life-cycle-ultrastructure-and-phylogeny-of-new-diplonemids-and-their-endosymbiotic-bacteria
#9
Daria Tashyreva, Galina Prokopchuk, Jan Votýpka, Akinori Yabuki, Aleš Horák, Julius Lukeš
Diplonemids represent a hyperdiverse and abundant yet poorly studied group of marine protists. Here we describe two new members of the genus Diplonema (Diplonemea, Euglenozoa), Diplonema japonicum sp. nov. and Diplonema aggregatum sp. nov., based on life cycle, morphology, and 18S rRNA gene sequences. Along with euglenozoan apomorphies, they contain several unique features. Their life cycle is complex, consisting of a trophic stage that is, following the depletion of nutrients, transformed into a sessile stage and subsequently into a swimming stage...
March 6, 2018: MBio
https://www.readbyqxmd.com/read/29449551/mutations-in-cfap43-and-cfap44-cause-male-infertility-and-flagellum-defects-in-trypanosoma-and-human
#10
Charles Coutton, Alexandra S Vargas, Amir Amiri-Yekta, Zine-Eddine Kherraf, Selima Fourati Ben Mustapha, Pauline Le Tanno, Clémentine Wambergue-Legrand, Thomas Karaouzène, Guillaume Martinez, Serge Crouzy, Abbas Daneshipour, Seyedeh Hanieh Hosseini, Valérie Mitchell, Lazhar Halouani, Ouafi Marrakchi, Mounir Makni, Habib Latrous, Mahmoud Kharouf, Jean-François Deleuze, Anne Boland, Sylviane Hennebicq, Véronique Satre, Pierre-Simon Jouk, Nicolas Thierry-Mieg, Beatrice Conne, Denis Dacheux, Nicolas Landrein, Alain Schmitt, Laurence Stouvenel, Patrick Lorès, Elma El Khouri, Serge P Bottari, Julien Fauré, Jean-Philippe Wolf, Karin Pernet-Gallay, Jessica Escoffier, Hamid Gourabi, Derrick R Robinson, Serge Nef, Emmanuel Dulioust, Raoudha Zouari, Mélanie Bonhivers, Aminata Touré, Christophe Arnoult, Pierre F Ray
Spermatogenesis defects concern millions of men worldwide, yet the vast majority remains undiagnosed. Here we report men with primary infertility due to multiple morphological abnormalities of the sperm flagella with severe disorganization of the sperm axoneme, a microtubule-based structure highly conserved throughout evolution. Whole-exome sequencing was performed on 78 patients allowing the identification of 22 men with bi-allelic mutations in DNAH1 (n = 6), CFAP43 (n = 10), and CFAP44 (n = 6)...
February 15, 2018: Nature Communications
https://www.readbyqxmd.com/read/29363196/regulation-of-sporangium-formation-by-the-orphan-response-regulator-tcra-in-the-rare-actinomycete-actinoplanes-missouriensis
#11
Yoshihiro Mouri, Moon-Sun Jang, Kenji Konishi, Aiko Hirata, Takeaki Tezuka, Yasuo Ohnishi
The rare actinomycete Actinoplanes missouriensis forms terminal sporangia containing a few hundred flagellated spores, which can swim in aquatic environments after release from sporangium. However, gene regulation for its characteristic morphological development is largely unknown. Here, we report the functional analysis of an orphan response regulator, TcrA, which is encoded next to the chemotaxis-flagellar gene cluster. The tcrA null (ΔtcrA) mutant formed sporangium, in which sporulation proceeded. However, many distorted spores were produced and some spores ectopically germinated in the mutant sporangia...
March 2018: Molecular Microbiology
https://www.readbyqxmd.com/read/29325341/-morphological-characteristics-and-phenotypic-analysis-of-multiple-morphological-abnormalities-in-sperm-flagella
#12
J X Wang, X Y Yang, H B Cheng, L Y Shen, G G Wang, Y C Shi, H Li, S M Yang
Objective: To analyze the sperm morphological characteristics of multiple morphological abnormalities of the sperm flagella (MMAF), and to analyze their common features and subtypes. Methods: Twenty-eight patients with abnormal morphology of flagella were analyzed by semen analysis. The morphological characteristics were analyzed by scanning electron microscopy and transmission electron microscopy. Histological observation of one case of testicular tissue was performed. Results: Of the 28 patients, only 13 patients (46...
December 26, 2017: Zhonghua Yi Xue za Zhi [Chinese medical journal]
https://www.readbyqxmd.com/read/29287245/host-and-symbiont-intraspecific-variability-the-case-of-paramecium-calkinsi-and-candidatus-trichorickettsia-mobilis
#13
E Sabaneyeva, M Castelli, F Szokoli, K Benken, N Lebedeva, A Salvetti, M Schweikert, S Fokin, G Petroni
Newly isolated strains of the ciliate Paramecium calkinsi and their cytoplasmic bacterial endosymbionts were characterized by a multidisciplinary approach, including live observation, ultrastructural investigation, and molecular analysis. Despite morphological resemblance, the characterized P. calkinsi strains showed a significant molecular divergence compared to conspecifics, possibly hinting for a cryptic speciation. The endosymbionts were clearly found to be affiliated to the species "Candidatus Trichorickettsia mobilis" (Rickettsiales, Rickettsiaceae), currently encompassing only bacteria retrieved in an obligate intracellular association with other ciliates...
February 2018: European Journal of Protistology
https://www.readbyqxmd.com/read/29179007/electron-microscopy-observations-on-testis-and-spermatozoa-of-leptodactylus-chaquensis-anura-leptodactylidae
#14
Lucrecia Iruzubieta Villagra, Inés Ramos, Susana Cisint, Claudia A Crespo, Silvia N Fernández
Scanning and transmission electron microscopy were used to investigate the fine structure of the testis and spermatozoa of toad Leptodactylus chaquensis. Our observations indicate that germinal compartment contains Sertoli (SC) and germ cells. The tight junctions and desmosomes among SC indicate the existence of an hematotesticular barrier in charge of maintaining the differences in the composition of the germinal and interstitial compartments. During spermatogenesis, SC acts as a structural support for germ cells...
February 2018: Micron: the International Research and Review Journal for Microscopy
https://www.readbyqxmd.com/read/29178204/tbsmee1-regulates-hook-complex-morphology-and-the-rate-of-flagellar-pocket-uptake-in-trypanosoma-brucei
#15
Jenna A Perry, Amy N Sinclair-Davis, Michael R McAllaster, Christopher L de Graffenried
Trypanosoma brucei uses multiple mechanisms to evade detection by its insect and mammalian hosts. The flagellar pocket (FP) is the exclusive site of uptake from the environment in trypanosomes and shields receptors from exposure to the host. The FP neck is tightly associated with the flagellum via a series of cytoskeletal structures that include the hook complex (HC) and the centrin arm. These structures are implicated in facilitating macromolecule entry into the FP and nucleating the flagellum attachment zone (FAZ), which adheres the flagellum to the cell surface...
February 2018: Molecular Microbiology
https://www.readbyqxmd.com/read/29155083/tbvps15-is-required-for-vesicular-transport-and-cytokinesis-in-trypanosoma-brucei
#16
Alejandra C Schoijet, Kildare Miranda, Tamara Sternlieb, Nadia M Barrera, Wendell Girard-Dias, Wanderley de Souza, Guillermo D Alonso
The class III phosphatidylinositol 3-kinase (PI3K) Vps34 is an important regulator of key cellular functions, including cell growth, survival, intracellular trafficking, autophagy and nutrient sensing. In yeast, Vps34 is associated with the putative serine/threonine protein kinase Vps15, however, its role in signaling has not been deeply evaluated. Here, we have identified the Vps15 orthologue in Trypanosoma brucei, named TbVps15. Knockdown of TbVps15 expression by interference RNA resulted in inhibition of cell growth and blockage of cytokinesis...
January 2018: Molecular and Biochemical Parasitology
https://www.readbyqxmd.com/read/29145009/sperm-morphology-of-predatory-pirate-bugs-amphiareus-constrictus-and-blaptostethus-pallescens-heteroptera-anthocoridae-with-phylogenetic-inferences
#17
Aline Beatriz Reis Santos, José Lino-Neto
The sperm morphology of two predatory bugs Amphiareus constrictus and Blaptostethus pallescens, representing the tribes Dufouriellini and Blasptostethini, respectively, was described using light and transmission electron microscopy. The spermatozoa of Amphiareus constrictus and Blaptostethus pallescens are fine and long, each measuring 216.6μm and 181.0μm in length, of which 37.0μm and 11.6μm, respectively, comprise the nuclei. When stained with DAPI (for DNA), the posterior half of the nucleus in B. pallescens exhibited low fluorescence, while in A...
February 2018: Micron: the International Research and Review Journal for Microscopy
https://www.readbyqxmd.com/read/29091964/interaction-between-the-flagellar-pocket-collar-and-the-hook-complex-via-a-novel-microtubule-binding-protein-in-trypanosoma-brucei
#18
Anna Albisetti, Célia Florimond, Nicolas Landrein, Keni Vidilaseris, Marie Eggenspieler, Johannes Lesigang, Gang Dong, Derrick Roy Robinson, Mélanie Bonhivers
Trypanosoma brucei belongs to a group of unicellular, flagellated parasites that are responsible for human African trypanosomiasis. An essential aspect of parasite pathogenicity is cytoskeleton remodelling, which occurs during the life cycle of the parasite and is accompanied by major changes in morphology and organelle positioning. The flagellum originates from the basal bodies and exits the cell body through the flagellar pocket (FP) but remains attached to the cell body via the flagellum attachment zone (FAZ)...
November 2017: PLoS Pathogens
https://www.readbyqxmd.com/read/29078369/extensive-flagellar-remodeling-during-the-complex-life-cycle-of-paratrypanosoma-an-early-branching-trypanosomatid
#19
Tomáš Skalický, Eva Dobáková, Richard J Wheeler, Martina Tesařová, Pavel Flegontov, Dagmar Jirsová, Jan Votýpka, Vyacheslav Yurchenko, Francisco J Ayala, Julius Lukeš
Paratrypanosoma confusum is a monoxenous kinetoplastid flagellate that constitutes the most basal branch of the highly diverse parasitic trypanosomatids, which include human pathogens Trypanosoma and Leishmania This makes Paratrypanosoma uniquely informative for the evolution of obligatory parasitism from free-living lifestyle and the evolution of human parasitism in some trypanosomatid lineages. It has typical promastigote morphology but also forms surface-attached haptomonads and amastigotes. Haptomonads form by attachment to a surface via a large bulge at the base of the flagellum, which is then remodeled into a thin attachment pad associated with flagellum shortening...
October 31, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28987651/ultrastructure-and-phylogeny-of-kirithra-asteri-gen-et-sp-nov-ceratoperidiniaceae-dinophyceae-a-free-living-thin-walled-marine-photosynthetic-dinoflagellate-from-argentina
#20
Pernille Vængebjerg Boutrup, Øjvind Moestrup, Urban Tillmann, Niels Daugbjerg
A gymnodinioid photosynthetic dinoflagellate was isolated from Argentina and examined by light and electron microscopy and analysis of nuclear-encoded LSU rDNA. Kirithra asteri gen. et sp. nov. was proposed as morphology and molecular phylogeny separated this dinoflagellate from others within the family Ceratoperidiniaceae. Cells were surrounded by a hyaline amphiesma comprising polygonal vesicles. Each vesicle contained a honeycomb and a trilaminar structure. An anterior sulcal extension ending in a complete circle formed the apical structure complex (ASC), which characterizes Ceratoperidiniaceae...
September 9, 2017: Protist
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