Limits...
Epicellular Apicomplexans: Parasites "On the Way In".

Bartošová-Sojková P, Oppenheim RD, Soldati-Favre D, Lukeš J - PLoS Pathog. (2015)

View Article: PubMed Central - PubMed

Affiliation: Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic.

AUTOMATICALLY GENERATED EXCERPT
Please rate it.

The Coccidia and the Cryptosporidia infect both cold- and warm-blooded vertebrates, yet members of the genera Toxoplasma, Eimeria, Sarcocystis, and Cryptosporidium (which mostly parasitize the latter hosts) have received most of the attention by far because of their importance to human and veterinary health... Our knowledge about a wide array of apicomplexans found in fish, amphibians, and reptiles is thus primarily confined to the morphological description of their exogenous stages (i.e., oocysts) and sites of infection, rarely with notes on pathogenicity... In the Coccidia of homeotherms, these developmental phases take place in different hosts, whereas the majority of the Coccidia of poikilotherms typically have direct life cycles... Phylogenetic analyses based on the 18S rRNA gene sequences, now available from a number of apicomplexans parasitizing cold-blooded vertebrates (e.g., members of the genera Cryptosporidium, Goussia, Acroeimeria, Eimeria, Calyptospora, and Choleoeimeria), allowed for the inference of their phylogenetic relationships... Merozoites of the epicellular species infecting fish, amphibians, and reptiles exhibit all the typical attributes of apicomplexans, yet they reside in a host-derived envelope that adopts diverse morphologies; consequently, these parasites likely rely on various modes of nutrient uptake... Importantly, an apical membrane antigen (AMA) family member and several rhoptry neck (RON) proteins discharged by the rhoptries that act as anchoring factors into the host cell cortical cytoskeleton participate in the formation of a junction through which the parasite squeezes to access the host cell... Interestingly, Cryptosporidium, which does not penetrate deeply into the host cytoplasm but remains epicellular, lacks AMAs and RONs that are necessary to form such a junction... The recently identified dense granules (GRAs) that function as effectors in subverting host cell function during Toxoplasma gondii tachyzoites infection cannot be found in G. janae... However, the aspartyl protease 5 involved in their processing and export beyond the PVM is present, which suggests that species-specific effectors likely exist in piscine coccidians... This versatility can be clearly exemplified by the metabolic flexibility of the epicellular Cryptosporidia... Indeed, intestinal human parasites Cryptosporidium parvum and C. hominis have undergone reductive evolution of their mitochondrion, leading to the loss of organellar DNA and several key functions (such as the tricarboxylic acid [TCA] cycle and respiratory chain), whereas the closely related gastric parasite of rodents, C. muris, has retained all enzymes of the TCA cycle and most complexes of the respiratory chain... The first RNA-seq analyses of the G. janae oocyst/sporozoite stages provide evidence that this coccidium possesses enzymes implicated in most of the central carbon metabolism, resembling the versatile metabolic capabilities of T. gondii rather than the reduced ones of Cryptosporidium spp. which, however, share with G. janae epicellular localization... These examples highlight potential differences in the nutrients available in each niche and specific adaptions of the parasite to thrive in its environment... In conclusion, the apicomplexans exhibit a remarkable diversity in the strategies they use for acquisition of nutrients, invasion, and interaction with host cells.

No MeSH data available.


Related in: MedlinePlus

Schematic interpretation of host–parasite interactions of epicellular piscine cryptosporidians and coccidians.Monopodial stage of Cryptosporidium molnari with the detail of feeder organelle (inset) (A; modified from Alvarez-Pellitero P, Palenzuela O, Sitjà-Bobadilla A. 2002. Cryptosporidium molnari n. sp. (Apicomplexa: Cryptosporidiidae) infecting two marine fish species, Sparus aurata L. and Dicentrarchus labrax L. Figs 23 and 30. International Journal for Parasitology 32: 1007–1021. Elsevier 2002), Cryptosporidium villithecus (B; adapted from Landsberg and Paperna, 1986), Goussia janae (C; adapted from Lukeš J, Starý V. 1992. Ultrastructure of life cycle stages of Goussia janae (Apicomplexa, Eimeriidae) and X-ray microanalysis of accompanying precipitates. Canadian Journal of Zoology, 70 (12): 2382–2397, 2008 Canadian Science Publishing or its licensors. Reproduced with permission), Eimeria anguillae (D), Goussia spraguei (E; adapted from A new species of Goussia (Apicomplexa, Coccidia) in the kidney tubules of the cod, Gadus morhua L. Morrison CM, Poynton SL. Journal of Fish Diseases 12 (6). 1989. John Wiley & Sons, Inc. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2761.1989.tb00564.x/abstract), Eimeria puytoraci (F), Eimeria vanasi with the detail of its protrusions into the host cell cytoplasm (inset) (G; adapted from Paperna, (1991). Kim and Paperna (1992)); Spider-like stage of Goussia pannonica (H; adapted from Life cycle of Goussia pannonica (Molnár, 1989) (Apicomplexa, Eimeriorina), an extracytoplasmic coccidium from the white bream Blicca bjoerkna. Lukeš J. Journal of Protozoology 39 (4). 1992 John Wiley & Sons, Inc. http://onlinelibrary.wiley.com/doi/10.1111/j.1550-7408.1992.tb04836.x/abstract). In all figures, the scale bar is 1 μm, with the exception of insets (0.2 μm in A and 0.3 μm in G).
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4581633&req=5

ppat.1005080.g002: Schematic interpretation of host–parasite interactions of epicellular piscine cryptosporidians and coccidians.Monopodial stage of Cryptosporidium molnari with the detail of feeder organelle (inset) (A; modified from Alvarez-Pellitero P, Palenzuela O, Sitjà-Bobadilla A. 2002. Cryptosporidium molnari n. sp. (Apicomplexa: Cryptosporidiidae) infecting two marine fish species, Sparus aurata L. and Dicentrarchus labrax L. Figs 23 and 30. International Journal for Parasitology 32: 1007–1021. Elsevier 2002), Cryptosporidium villithecus (B; adapted from Landsberg and Paperna, 1986), Goussia janae (C; adapted from Lukeš J, Starý V. 1992. Ultrastructure of life cycle stages of Goussia janae (Apicomplexa, Eimeriidae) and X-ray microanalysis of accompanying precipitates. Canadian Journal of Zoology, 70 (12): 2382–2397, 2008 Canadian Science Publishing or its licensors. Reproduced with permission), Eimeria anguillae (D), Goussia spraguei (E; adapted from A new species of Goussia (Apicomplexa, Coccidia) in the kidney tubules of the cod, Gadus morhua L. Morrison CM, Poynton SL. Journal of Fish Diseases 12 (6). 1989. John Wiley & Sons, Inc. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2761.1989.tb00564.x/abstract), Eimeria puytoraci (F), Eimeria vanasi with the detail of its protrusions into the host cell cytoplasm (inset) (G; adapted from Paperna, (1991). Kim and Paperna (1992)); Spider-like stage of Goussia pannonica (H; adapted from Life cycle of Goussia pannonica (Molnár, 1989) (Apicomplexa, Eimeriorina), an extracytoplasmic coccidium from the white bream Blicca bjoerkna. Lukeš J. Journal of Protozoology 39 (4). 1992 John Wiley & Sons, Inc. http://onlinelibrary.wiley.com/doi/10.1111/j.1550-7408.1992.tb04836.x/abstract). In all figures, the scale bar is 1 μm, with the exception of insets (0.2 μm in A and 0.3 μm in G).

Mentions: Based on ultrastructural features, we distinguish eight types of host–parasite interfaces among epicellular species from fish and reptiles that fit into the monopodial (single attachment zone; 1–7) types or multipodial (8) types: (1) MFO in the contact zone with smooth outer host cell membrane (Fig 2A) [10]; (2) MFO in the contact zone with microvillous surface of the outer host cell membrane (Fig 2B) [11]; (3) smooth contact zone without any protrusions (Fig 2C) [9]; (4) regular finger-like protrusions of the PV into the host cytoplasm, filled with globular granules (Fig 2D) (Lukeš J, unpublished results); (5) deep irregular invaginations of the PV filled with dense granular material (Fig 2E) [12]; (6) smooth interface with abundant granular, material-containing verrucous protuberances on the outer enterocyte membrane (Fig 2F); (7) numerous long tubular formations extending from the PV, which carries small projections or ridges on its luminal side (Fig 2G) [13,14]; (8) spider-like stages localized above the microvillar region that are connected with the host cytoplasm via several projections (Fig 2H) [15].


Epicellular Apicomplexans: Parasites "On the Way In".

Bartošová-Sojková P, Oppenheim RD, Soldati-Favre D, Lukeš J - PLoS Pathog. (2015)

Schematic interpretation of host–parasite interactions of epicellular piscine cryptosporidians and coccidians.Monopodial stage of Cryptosporidium molnari with the detail of feeder organelle (inset) (A; modified from Alvarez-Pellitero P, Palenzuela O, Sitjà-Bobadilla A. 2002. Cryptosporidium molnari n. sp. (Apicomplexa: Cryptosporidiidae) infecting two marine fish species, Sparus aurata L. and Dicentrarchus labrax L. Figs 23 and 30. International Journal for Parasitology 32: 1007–1021. Elsevier 2002), Cryptosporidium villithecus (B; adapted from Landsberg and Paperna, 1986), Goussia janae (C; adapted from Lukeš J, Starý V. 1992. Ultrastructure of life cycle stages of Goussia janae (Apicomplexa, Eimeriidae) and X-ray microanalysis of accompanying precipitates. Canadian Journal of Zoology, 70 (12): 2382–2397, 2008 Canadian Science Publishing or its licensors. Reproduced with permission), Eimeria anguillae (D), Goussia spraguei (E; adapted from A new species of Goussia (Apicomplexa, Coccidia) in the kidney tubules of the cod, Gadus morhua L. Morrison CM, Poynton SL. Journal of Fish Diseases 12 (6). 1989. John Wiley & Sons, Inc. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2761.1989.tb00564.x/abstract), Eimeria puytoraci (F), Eimeria vanasi with the detail of its protrusions into the host cell cytoplasm (inset) (G; adapted from Paperna, (1991). Kim and Paperna (1992)); Spider-like stage of Goussia pannonica (H; adapted from Life cycle of Goussia pannonica (Molnár, 1989) (Apicomplexa, Eimeriorina), an extracytoplasmic coccidium from the white bream Blicca bjoerkna. Lukeš J. Journal of Protozoology 39 (4). 1992 John Wiley & Sons, Inc. http://onlinelibrary.wiley.com/doi/10.1111/j.1550-7408.1992.tb04836.x/abstract). In all figures, the scale bar is 1 μm, with the exception of insets (0.2 μm in A and 0.3 μm in G).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4581633&req=5

ppat.1005080.g002: Schematic interpretation of host–parasite interactions of epicellular piscine cryptosporidians and coccidians.Monopodial stage of Cryptosporidium molnari with the detail of feeder organelle (inset) (A; modified from Alvarez-Pellitero P, Palenzuela O, Sitjà-Bobadilla A. 2002. Cryptosporidium molnari n. sp. (Apicomplexa: Cryptosporidiidae) infecting two marine fish species, Sparus aurata L. and Dicentrarchus labrax L. Figs 23 and 30. International Journal for Parasitology 32: 1007–1021. Elsevier 2002), Cryptosporidium villithecus (B; adapted from Landsberg and Paperna, 1986), Goussia janae (C; adapted from Lukeš J, Starý V. 1992. Ultrastructure of life cycle stages of Goussia janae (Apicomplexa, Eimeriidae) and X-ray microanalysis of accompanying precipitates. Canadian Journal of Zoology, 70 (12): 2382–2397, 2008 Canadian Science Publishing or its licensors. Reproduced with permission), Eimeria anguillae (D), Goussia spraguei (E; adapted from A new species of Goussia (Apicomplexa, Coccidia) in the kidney tubules of the cod, Gadus morhua L. Morrison CM, Poynton SL. Journal of Fish Diseases 12 (6). 1989. John Wiley & Sons, Inc. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2761.1989.tb00564.x/abstract), Eimeria puytoraci (F), Eimeria vanasi with the detail of its protrusions into the host cell cytoplasm (inset) (G; adapted from Paperna, (1991). Kim and Paperna (1992)); Spider-like stage of Goussia pannonica (H; adapted from Life cycle of Goussia pannonica (Molnár, 1989) (Apicomplexa, Eimeriorina), an extracytoplasmic coccidium from the white bream Blicca bjoerkna. Lukeš J. Journal of Protozoology 39 (4). 1992 John Wiley & Sons, Inc. http://onlinelibrary.wiley.com/doi/10.1111/j.1550-7408.1992.tb04836.x/abstract). In all figures, the scale bar is 1 μm, with the exception of insets (0.2 μm in A and 0.3 μm in G).
Mentions: Based on ultrastructural features, we distinguish eight types of host–parasite interfaces among epicellular species from fish and reptiles that fit into the monopodial (single attachment zone; 1–7) types or multipodial (8) types: (1) MFO in the contact zone with smooth outer host cell membrane (Fig 2A) [10]; (2) MFO in the contact zone with microvillous surface of the outer host cell membrane (Fig 2B) [11]; (3) smooth contact zone without any protrusions (Fig 2C) [9]; (4) regular finger-like protrusions of the PV into the host cytoplasm, filled with globular granules (Fig 2D) (Lukeš J, unpublished results); (5) deep irregular invaginations of the PV filled with dense granular material (Fig 2E) [12]; (6) smooth interface with abundant granular, material-containing verrucous protuberances on the outer enterocyte membrane (Fig 2F); (7) numerous long tubular formations extending from the PV, which carries small projections or ridges on its luminal side (Fig 2G) [13,14]; (8) spider-like stages localized above the microvillar region that are connected with the host cytoplasm via several projections (Fig 2H) [15].

View Article: PubMed Central - PubMed

Affiliation: Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic.

AUTOMATICALLY GENERATED EXCERPT
Please rate it.

The Coccidia and the Cryptosporidia infect both cold- and warm-blooded vertebrates, yet members of the genera Toxoplasma, Eimeria, Sarcocystis, and Cryptosporidium (which mostly parasitize the latter hosts) have received most of the attention by far because of their importance to human and veterinary health... Our knowledge about a wide array of apicomplexans found in fish, amphibians, and reptiles is thus primarily confined to the morphological description of their exogenous stages (i.e., oocysts) and sites of infection, rarely with notes on pathogenicity... In the Coccidia of homeotherms, these developmental phases take place in different hosts, whereas the majority of the Coccidia of poikilotherms typically have direct life cycles... Phylogenetic analyses based on the 18S rRNA gene sequences, now available from a number of apicomplexans parasitizing cold-blooded vertebrates (e.g., members of the genera Cryptosporidium, Goussia, Acroeimeria, Eimeria, Calyptospora, and Choleoeimeria), allowed for the inference of their phylogenetic relationships... Merozoites of the epicellular species infecting fish, amphibians, and reptiles exhibit all the typical attributes of apicomplexans, yet they reside in a host-derived envelope that adopts diverse morphologies; consequently, these parasites likely rely on various modes of nutrient uptake... Importantly, an apical membrane antigen (AMA) family member and several rhoptry neck (RON) proteins discharged by the rhoptries that act as anchoring factors into the host cell cortical cytoskeleton participate in the formation of a junction through which the parasite squeezes to access the host cell... Interestingly, Cryptosporidium, which does not penetrate deeply into the host cytoplasm but remains epicellular, lacks AMAs and RONs that are necessary to form such a junction... The recently identified dense granules (GRAs) that function as effectors in subverting host cell function during Toxoplasma gondii tachyzoites infection cannot be found in G. janae... However, the aspartyl protease 5 involved in their processing and export beyond the PVM is present, which suggests that species-specific effectors likely exist in piscine coccidians... This versatility can be clearly exemplified by the metabolic flexibility of the epicellular Cryptosporidia... Indeed, intestinal human parasites Cryptosporidium parvum and C. hominis have undergone reductive evolution of their mitochondrion, leading to the loss of organellar DNA and several key functions (such as the tricarboxylic acid [TCA] cycle and respiratory chain), whereas the closely related gastric parasite of rodents, C. muris, has retained all enzymes of the TCA cycle and most complexes of the respiratory chain... The first RNA-seq analyses of the G. janae oocyst/sporozoite stages provide evidence that this coccidium possesses enzymes implicated in most of the central carbon metabolism, resembling the versatile metabolic capabilities of T. gondii rather than the reduced ones of Cryptosporidium spp. which, however, share with G. janae epicellular localization... These examples highlight potential differences in the nutrients available in each niche and specific adaptions of the parasite to thrive in its environment... In conclusion, the apicomplexans exhibit a remarkable diversity in the strategies they use for acquisition of nutrients, invasion, and interaction with host cells.

No MeSH data available.


Related in: MedlinePlus