Centrin in the groove: immunolocalisation of centrin and microtubules in the putatively primitive protistChilomastix cuspidata (Retortamonadida)

Weerakoon, N. D.; Harper, John; Simpson, Alastair G. B.; Patterson, David J.

doi:10.1007/bf01314957

Cited by 10 publications

(4 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Fourthly, this account highlights the tendency for the IRR to be closely associated with endoplasmic reticulum. This has been reported in Carpediemonas, T. marina , and Chilomastix cuspidata (Simpson and Patterson 1999; Simpson, Bernard, and Patterson 2000; Weerakoon et al 1999). These observations lend further support to the hypotheses that the B fibres, composite fibres, and IRRs of core jakobids are indeed homologous to the synonymous structures in other excavate taxa.…”

Section: Discussionsupporting

confidence: 64%

On Core Jakobids and Excavate Taxa: The Ultrastructure of Jakoba incarcerata

Simpson

Patterson

2001

J Eukaryotic Microbiology

View full text Add to dashboard Cite

The cellular organisation of the 'excavate' flagellate Jakoba incarcerata Bernard, Simpson and Patterson 2000 is described. Cells have one nucleus and dictyosome. The putative mitochondria lack cristae. Two flagella (anterior and posterior) insert anterior to the feeding groove. The posterior flagellum bears a dorsal vane. An 'anterior' microtubular root arises against the anterior basal body. Two main microtubular roots, left and right, and a singlet 'root' arise around the posterior basal body and support the groove. Non-microtubular fibres termed 'A', 'B', 'I', and 'composite' associate with the right root. A multilaminar 'C' fibre associates with the left root. The cytoskeleton of J. incarcerata indicates a common ancestry with other excavate taxa (i.e. diplomonads, retortamonads, heteroloboseids, 'core jakobids', Malawimonas, Carpediemonas, and Trimastix). Overall, J. incarcerata is most similar to (other) core jakobids, namely Jakoba libera, Reclinomonas, and Histiona. We regard J. incarcerata as a core jakobid and identify the group by the synapomorphy 'vanes restricted to dorsal side of the posterior flagellum'. The anterior root and position of the B fibre (and presence of dense inclusions in the cartwheels and a conscpicuous singlet root-associated fibre) in J. incarcerata are novel for core jakobids and argue for close relationships with Trimastix and/or Heterolobosea. The C fibre is similar in substructure to the costal fibre of parabasalids and it is possible that the structures are homologous.

show abstract

Section: Discussionsupporting

confidence: 64%

On Core Jakobids and Excavate Taxa: The Ultrastructure of Jakoba incarcerata

Simpson

Patterson

2001

J Eukaryotic Microbiology

View full text Add to dashboard Cite

show abstract

“…Centrin-containing fibers have been found in other excavate groups, such as trichomonads (10), retortamonads (39), and diplomonads (6), and other flagellates, including the chrysomonads (11), the dinoflagellates (27), and Chlamydomonas (38), but this in itself is not strong evidence for the existence of bilobe homologs. At this point, taxonomic sampling is too widespread and infrequent to make any reasonable inferences regarding the evolution of a morphologically and biochemically complex structure.…”

Section: Discussionmentioning

confidence: 99%

Morphology of the Trypanosome Bilobe, a Novel Cytoskeletal Structure

et al. 2012

View full text Add to dashboard Cite

The trypanosome bilobe is a cytoskeletal structure of unclear function. To date, four proteins have been shown to localize stably to it: TbMORN1, TbLRRP1, TbCentrin2, and TbCentrin4. In this study, a combination of immunofluorescence microscopy and electron microscopy was used to explore the morphology of the bilobe and its relationship to other nearby cytoskeletal structures in the African trypanosome procyclic trypomastigote. The use of detergent/salt-extracted flagellum preparations was found to be an effective way of discerning features of the cytoskeletal ultrastructure that are normally obscured. TbMORN1 and TbCentrin4 together define a hairpin structure comprising an arm of TbCentrin4 and a fishhook of TbMORN1. The two arms flank a specialized microtubule quartet and the flagellum attachment zone filament, with TbMORN1 running alongside the former and TbCentrin4 alongside the latter. The hooked part of TbMORN1 sits atop the flagellar pocket collar marked by TbBILBO1. The TbMORN1 bilobe occasionally exhibits tendrillar extensions that seem to be connected to the basal and probasal bodies. The TbMORN1 molecules present on these tendrils undergo higher rates of turnover than those for molecules on the main bilobe structure. These observations have been integrated with previous detailed descriptions of the cytoskeletal elements in trypanosome cells.

show abstract

“…The extent to which the cytopharynx extends back up the dorsal side of the cell in barthelonids and skoliomonads is unusual among metamonads. The most similar case is in the predominantly commensal retortamonads, which have an elongate cytopharynx at the posterior of the groove that curves leftwards and then anteriorly (Bernard et al, 1997; Kulda et al, 2017); this extension is most notable in free-living Chilomastix cuspidata , though the cytopharynx does not extend all the way up the anterior (Bernard et al, 1997; Weerakoon et al, 1999).…”

Section: Discussionmentioning

confidence: 99%

Characterisation ofSkoliomonasgen. nov., a haloalkaliphilic anaerobe related to barthelonids (Metamonada)

Eglit,

Williams,

Roger

et al. 2024

Preprint

View full text Add to dashboard Cite

Metamonads are a large and exclusively anaerobic clade of protists. Additionally, metamonads are one of the three clades with a proposed 'excavate' ancestral cell morphology, characterised by a conspicuous ventral groove often accompanied by a posterior flagellum with a vane. Here, we characterise four isolates of an anaerobic bacterivorous flagellate from hypersaline and alkaline soda lake environments, which represents a novel clade. Small subunit ribosomal RNA (SSU rRNA) gene phylogenies support recent phylogenomic analyses in placing this clade as the sister group toBarthelonaspp., a lineage that is itself sister to or deeply branching within Fornicata (Metamonada). The cells have a distinctive morphology comprised of a hunchbacked cell body with a narrow twisting ventral groove ending in a large opening to a conspicuous cytopharynx curving up the dorsal side of the cell. The right margin of the groove is defined by a thin 'lip' that twists slightly to the left towards the posterior. The posterior of the cell ends in a spike up to half a cell body long. The posterior flagellum bears a wide ventral-facing vane. One isolate forms cysts with a complex wall and a single plug. The narrow ventral groove and elongate cytopharynx are shared with barthelonids. We describe one isolate asSkoliomonas litria, gen. et sp. nov. Further investigation of mitochondrial-related organelles (MRO) inSkoliomonasspp. and detailed ultrastructural studies would be important to understanding the evolution of adaptation to anaerobic conditions in Metamonads—especially fornicates—as well as the evolution of the 'excavate' groove.

show abstract

Centrin in the groove: immunolocalisation of centrin and microtubules in the putatively primitive protistChilomastix cuspidata (Retortamonadida)

Cited by 10 publications

References 42 publications

On Core Jakobids and Excavate Taxa: The Ultrastructure of Jakoba incarcerata

On Core Jakobids and Excavate Taxa: The Ultrastructure of Jakoba incarcerata

Morphology of the Trypanosome Bilobe, a Novel Cytoskeletal Structure

Characterisation ofSkoliomonasgen. nov., a haloalkaliphilic anaerobe related to barthelonids (Metamonada)

Contact Info

Product

Resources

About