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Myung Gil Park - One of the best experts on this subject based on the ideXlab platform.

  • dinophysis Caudata dinophyceae sequesters and retains plastids from the mixotrophic ciliate prey mesodinium rubrum 1
    Journal of Phycology, 2012
    Co-Authors: Woongghi Shin, Wayne D Coats, Myung Gil Park
    Abstract:

    "Phototrophic"Dinophysis Ehrenberg species are well known to have chloroplasts of a cryptophyte origin, more specifically of the cryptophyte genus complex Teleaulax/Geminigera. Nonetheless, whether chloroplasts of "phototrophic"Dinophysis are permanent plastids or periodically derived kleptoplastids (stolen chloroplasts) has not been confirmed. Indeed, molecular sequence data and ultrastructural data lead to contradictory interpretations about the status of Dinophysis plastids. Here, we used established cultures of D. Caudata strain DC-LOHABE01 and M. rubrum strain MR-MAL01 to address the status of Dinophysis plastids. Our approach was to experimentally generate D. Caudata with "green" plastids and then follow the ingestion and fate of "reddish-brown" prey plastids using light microscopy, time-lapse videography, and single-cell TEM. Our results for D. Caudata resolve the apparent discrepancy between morphological and molecular data by showing that plastids acquired when feeding on M. rubrum are structurally modified and retained as stellate compound chloroplasts characteristic of Dinophysis species.

  • does dinophysis Caudata dinophyceae have permanent plastids
    Journal of Phycology, 2010
    Co-Authors: Myung Gil Park
    Abstract:

    The marine photosynthetic dinoflagellates Dinophysis Ehrenb. species are obligate mixotrophs that require both light and the ciliate prey Myrionecta rubra (= Mesodinium rubrum) for long-term survival. Despite rapid progress on the study of Dinophysis using laboratory cultures, however, whether it has its own permanent plastids or kleptoplastids (i.e., stolen plastids from its ciliate prey) is not fully resolved. Here, we addressed this issue using established cultures of D. Caudata Saville-Kent strain DC-LOHABE01 and cross-feeding/starvation experiments encompassing the prey M. rubra strain MR-MAL01 cultures grown on two different cryptophytes (strains CR-MAL01 and CR-MAL11). To follow the fate of prey plastids, psbA gene as a tracer was amplified from individually isolated D. Caudata cells, and the PCR products were digested with a restriction enzyme, SfaNI. The RFLP pattern of the PCR products digested by SfaNI revealed that D. Caudata continued to keep CR-MAL01–type plastids, while it lost CR-MAL11–type plastids with increasing starvation time. Our results suggest that Dinophysis treats in different ways plastids taken up from different cryptophytes via its ciliate prey M. rubra. Alternatively, D. Caudata may already have its own CR-MAL01–type permanent plastid, with two types of plastids (CR-MAL01 and CR-MAL11) obtained from M. rubra being lost within 1 month. This result highlights the need to identify more accurately the origin of plastids in newly isolated photosynthetic Dinophysis species to resolve the issue of plastid permanence.

  • plastid dynamics during survival of dinophysis Caudata without its ciliate prey1
    Journal of Phycology, 2008
    Co-Authors: Myung Gil Park, Jong Soo Park
    Abstract:

    To survive, the marine dinoflagellate Dinophysis Caudata Saville-Kent must feed on the plastidic ciliate Myrionecta rubra (=Mesodinium rubrum), itself a consumer of cryptophytes. Whether D. Caudata has its own permanent chloroplasts or retains plastids from its ciliate prey, however, remains unresolved. Further, how long D. Caudata plastids (or kleptoplastids) persist and remain photosynthetically active in the absence of prey remains unknown. We addressed those issues here, using the first established culture of D. Caudata. Phylogenetic analyses of the plastid 16S rRNA and psbA gene sequences directly from the three organisms (D. Caudata, M. rubra, and a cryptophyte) revealed that the sequences of both genes from the three organisms are almost identical to each other, supporting that the plastids of D. Caudata are kleptoplastids. A 3-month starvation experiment revealed that D. Caudata can remain photosynthetically active for ∼2 months when not supplied with prey. D. Caudata cells starved for more than 2 months continued to keep the plastid 16S rRNA gene but lost the photosynthesis-related genes (i.e., psaA and psbA genes). When the prey was available again, however, D. Caudata cells starved for more than 2 months were able to reacquire plastids and slowly resumed photosynthetic activity. Taken all together, the results indicate that the nature of the relationship between D. Caudata and its plastids is not that of permanent cellular acquisitions. D. Caudata is an intriguing protist that would represent an interesting evolutionary adaptation with regard to photosynthesis as well as help us to better understand plastid evolution in eukaryotes.

  • plastid dynamics during survival of dinophysis Caudata without its ciliate prey 1
    Journal of Phycology, 2008
    Co-Authors: Myung Gil Park, Jong Soo Park, Miran Kim, Wonho Yih
    Abstract:

    To survive, the marine dinoflagellate Dinophysis Caudata Saville-Kent must feed on the plastidic ciliate Myrionecta rubra (=Mesodinium rubrum), itself a consumer of cryptophytes. Whether D. Caudata has its own permanent chloroplasts or retains plastids from its ciliate prey, however, remains unresolved. Further, how long D. Caudata plastids (or kleptoplastids) persist and remain photosynthetically active in the absence of prey remains unknown. We addressed those issues here, using the first established culture of D. Caudata. Phylogenetic analyses of the plastid 16S rRNA and psbA gene sequences directly from the three organisms (D. Caudata, M. rubra, and a cryptophyte) revealed that the sequences of both genes from the three organisms are almost identical to each other, supporting that the plastids of D. Caudata are kleptoplastids. A 3-month starvation experiment revealed that D. Caudata can remain photosynthetically active for ∼2 months when not supplied with prey. D. Caudata cells starved for more than 2 months continued to keep the plastid 16S rRNA gene but lost the photosynthesis-related genes (i.e., psaA and psbA genes). When the prey was available again, however, D. Caudata cells starved for more than 2 months were able to reacquire plastids and slowly resumed photosynthetic activity. Taken all together, the results indicate that the nature of the relationship between D. Caudata and its plastids is not that of permanent cellular acquisitions. D. Caudata is an intriguing protist that would represent an interesting evolutionary adaptation with regard to photosynthesis as well as help us to better understand plastid evolution in eukaryotes.

Rogé Jean - One of the best experts on this subject based on the ideXlab platform.

Jong Soo Park - One of the best experts on this subject based on the ideXlab platform.

  • plastid dynamics during survival of dinophysis Caudata without its ciliate prey1
    Journal of Phycology, 2008
    Co-Authors: Myung Gil Park, Jong Soo Park
    Abstract:

    To survive, the marine dinoflagellate Dinophysis Caudata Saville-Kent must feed on the plastidic ciliate Myrionecta rubra (=Mesodinium rubrum), itself a consumer of cryptophytes. Whether D. Caudata has its own permanent chloroplasts or retains plastids from its ciliate prey, however, remains unresolved. Further, how long D. Caudata plastids (or kleptoplastids) persist and remain photosynthetically active in the absence of prey remains unknown. We addressed those issues here, using the first established culture of D. Caudata. Phylogenetic analyses of the plastid 16S rRNA and psbA gene sequences directly from the three organisms (D. Caudata, M. rubra, and a cryptophyte) revealed that the sequences of both genes from the three organisms are almost identical to each other, supporting that the plastids of D. Caudata are kleptoplastids. A 3-month starvation experiment revealed that D. Caudata can remain photosynthetically active for ∼2 months when not supplied with prey. D. Caudata cells starved for more than 2 months continued to keep the plastid 16S rRNA gene but lost the photosynthesis-related genes (i.e., psaA and psbA genes). When the prey was available again, however, D. Caudata cells starved for more than 2 months were able to reacquire plastids and slowly resumed photosynthetic activity. Taken all together, the results indicate that the nature of the relationship between D. Caudata and its plastids is not that of permanent cellular acquisitions. D. Caudata is an intriguing protist that would represent an interesting evolutionary adaptation with regard to photosynthesis as well as help us to better understand plastid evolution in eukaryotes.

  • plastid dynamics during survival of dinophysis Caudata without its ciliate prey 1
    Journal of Phycology, 2008
    Co-Authors: Myung Gil Park, Jong Soo Park, Miran Kim, Wonho Yih
    Abstract:

    To survive, the marine dinoflagellate Dinophysis Caudata Saville-Kent must feed on the plastidic ciliate Myrionecta rubra (=Mesodinium rubrum), itself a consumer of cryptophytes. Whether D. Caudata has its own permanent chloroplasts or retains plastids from its ciliate prey, however, remains unresolved. Further, how long D. Caudata plastids (or kleptoplastids) persist and remain photosynthetically active in the absence of prey remains unknown. We addressed those issues here, using the first established culture of D. Caudata. Phylogenetic analyses of the plastid 16S rRNA and psbA gene sequences directly from the three organisms (D. Caudata, M. rubra, and a cryptophyte) revealed that the sequences of both genes from the three organisms are almost identical to each other, supporting that the plastids of D. Caudata are kleptoplastids. A 3-month starvation experiment revealed that D. Caudata can remain photosynthetically active for ∼2 months when not supplied with prey. D. Caudata cells starved for more than 2 months continued to keep the plastid 16S rRNA gene but lost the photosynthesis-related genes (i.e., psaA and psbA genes). When the prey was available again, however, D. Caudata cells starved for more than 2 months were able to reacquire plastids and slowly resumed photosynthetic activity. Taken all together, the results indicate that the nature of the relationship between D. Caudata and its plastids is not that of permanent cellular acquisitions. D. Caudata is an intriguing protist that would represent an interesting evolutionary adaptation with regard to photosynthesis as well as help us to better understand plastid evolution in eukaryotes.

Maximino Delgado - One of the best experts on this subject based on the ideXlab platform.

  • dinophysis diegensis is a life history stage of dinophysis Caudata dinophyceae dinophysiales
    Journal of Phycology, 2007
    Co-Authors: B Reguera, S Gonzalezgil, Maximino Delgado
    Abstract:

    Several species of Dinophysis Ehrenb. have been observed to produce “small cells” that are different in size and shape from the vegetative cells, following a reductionary division under certain environmental conditions, as part of a polymorphic life cycle. Based on observations on fixed field samples, D. diegensis Kof. was hypothesized to be a small form of D. Caudata Saville-Kent. In this study, this hypothesis was confirmed after incubations, in cell culture chambers, of groups of individually picked vegetative cells from natural populations of D. Caudata. Eight to 10 d after inoculation, different life-cycle stages were observed in the wells. Illustrations of small and intermediate forms of D. Caudata developed in vitro were contrasted with those observed during their proliferation in the northeast Atlantic (Galicia) and northwest Mediterranean (Catalonia) coasts of Iberia. It is proposed that Dinophysis diegensis–like specimens should be considered as a taxonomic (or heterotypic) synonym of Dinophysis Caudata. A historical overview is provided (see Supplementary material) that revises the large list of taxa used to nominate different morphotypes of D. Caudata, and its small and intermediate cells, since its original description by Saville-Kent in 1881.

Wonho Yih - One of the best experts on this subject based on the ideXlab platform.

  • plastid dynamics during survival of dinophysis Caudata without its ciliate prey 1
    Journal of Phycology, 2008
    Co-Authors: Myung Gil Park, Jong Soo Park, Miran Kim, Wonho Yih
    Abstract:

    To survive, the marine dinoflagellate Dinophysis Caudata Saville-Kent must feed on the plastidic ciliate Myrionecta rubra (=Mesodinium rubrum), itself a consumer of cryptophytes. Whether D. Caudata has its own permanent chloroplasts or retains plastids from its ciliate prey, however, remains unresolved. Further, how long D. Caudata plastids (or kleptoplastids) persist and remain photosynthetically active in the absence of prey remains unknown. We addressed those issues here, using the first established culture of D. Caudata. Phylogenetic analyses of the plastid 16S rRNA and psbA gene sequences directly from the three organisms (D. Caudata, M. rubra, and a cryptophyte) revealed that the sequences of both genes from the three organisms are almost identical to each other, supporting that the plastids of D. Caudata are kleptoplastids. A 3-month starvation experiment revealed that D. Caudata can remain photosynthetically active for ∼2 months when not supplied with prey. D. Caudata cells starved for more than 2 months continued to keep the plastid 16S rRNA gene but lost the photosynthesis-related genes (i.e., psaA and psbA genes). When the prey was available again, however, D. Caudata cells starved for more than 2 months were able to reacquire plastids and slowly resumed photosynthetic activity. Taken all together, the results indicate that the nature of the relationship between D. Caudata and its plastids is not that of permanent cellular acquisitions. D. Caudata is an intriguing protist that would represent an interesting evolutionary adaptation with regard to photosynthesis as well as help us to better understand plastid evolution in eukaryotes.