Release of lysosomal enzymes in Tetrahymena: a Ca²⁺-dependent secretory process

Autores
Tiedtke, Arno; Rasmussen, Leif; Florin Christensen, Jorge; Florin Christensen, Monica
Año de publicación
1988
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
The ciliate Tetrahymena thermophila releases lysosomal enzymes into nutrient and starvation media. We show here that this process occurs selectively, i.e. without leakage of cytoplasmic components, as indicated by lack of release of isocitrate dehydrogenase, a cytosolic enzyme with high activity in Tetrahymena . The role of intracellular Ca²⁺ in the process was also investigated. The Ca²⁺ ionophore A23187 has strong stimulatory effects on this release. Ionophore stimulation is maximal in the presence of extracellular Ca²⁺ but can occur also in its absence. Quin 2 fluorescence measurements indicate that intracellular Ca²⁺ increases in both cases. Mg²⁺ completely prevents the stimulatory effects of A23187. Ionomycin, another Ca²⁺ ionophore, also stimulates lysosomal enzyme release with a maximal response in the presence of extracellular Ca²⁺ . Measurements of extracellular isocitrate dehydrogenase showed that ionophore-stimulated lysosomal enzyme release can take place without leakage of cytoplasmic components. The observations that divalent cation ionophores stimulate selective lysosomal enzyme release and that this effect is strongest in the presence of external Ca²⁺ indicate that this cation plays a crucial role in the control of this process in Tetrahymena . Together with other observations they support the view that a subpopulation of Tetrahymena lysosomes has properties like those of secretory vesicles.
Centro de Estudios Parasitológicos y de Vectores
Materia
Biología
Lysosomal enzymes
Secretion
Tetrahymena thermophila
Nivel de accesibilidad
acceso abierto
Condiciones de uso
http://creativecommons.org/licenses/by-nc-sa/4.0/
Repositorio
SEDICI (UNLP)
Institución
Universidad Nacional de La Plata
OAI Identificador
oai:sedici.unlp.edu.ar:10915/142727

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network_name_str SEDICI (UNLP)
spelling Release of lysosomal enzymes in Tetrahymena: a Ca²⁺-dependent secretory processTiedtke, ArnoRasmussen, LeifFlorin Christensen, JorgeFlorin Christensen, MonicaBiologíaLysosomal enzymesSecretionTetrahymena thermophilaThe ciliate Tetrahymena thermophila releases lysosomal enzymes into nutrient and starvation media. We show here that this process occurs selectively, i.e. without leakage of cytoplasmic components, as indicated by lack of release of isocitrate dehydrogenase, a cytosolic enzyme with high activity in Tetrahymena . The role of intracellular Ca²⁺ in the process was also investigated. The Ca²⁺ ionophore A23187 has strong stimulatory effects on this release. Ionophore stimulation is maximal in the presence of extracellular Ca²⁺ but can occur also in its absence. Quin 2 fluorescence measurements indicate that intracellular Ca²⁺ increases in both cases. Mg²⁺ completely prevents the stimulatory effects of A23187. Ionomycin, another Ca²⁺ ionophore, also stimulates lysosomal enzyme release with a maximal response in the presence of extracellular Ca²⁺ . Measurements of extracellular isocitrate dehydrogenase showed that ionophore-stimulated lysosomal enzyme release can take place without leakage of cytoplasmic components. The observations that divalent cation ionophores stimulate selective lysosomal enzyme release and that this effect is strongest in the presence of external Ca²⁺ indicate that this cation plays a crucial role in the control of this process in Tetrahymena . Together with other observations they support the view that a subpopulation of Tetrahymena lysosomes has properties like those of secretory vesicles.Centro de Estudios Parasitológicos y de Vectores1988-05-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdf167-171http://sedici.unlp.edu.ar/handle/10915/142727enginfo:eu-repo/semantics/altIdentifier/issn/1477-9137info:eu-repo/semantics/altIdentifier/issn/0021-9533info:eu-repo/semantics/altIdentifier/doi/10.1242/jcs.90.1.167info:eu-repo/semantics/openAccesshttp://creativecommons.org/licenses/by-nc-sa/4.0/Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)reponame:SEDICI (UNLP)instname:Universidad Nacional de La Platainstacron:UNLP2025-09-29T11:31:52Zoai:sedici.unlp.edu.ar:10915/142727Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-29 11:31:52.332SEDICI (UNLP) - Universidad Nacional de La Platafalse
dc.title.none.fl_str_mv Release of lysosomal enzymes in Tetrahymena: a Ca²⁺-dependent secretory process
title Release of lysosomal enzymes in Tetrahymena: a Ca²⁺-dependent secretory process
spellingShingle Release of lysosomal enzymes in Tetrahymena: a Ca²⁺-dependent secretory process
Tiedtke, Arno
Biología
Lysosomal enzymes
Secretion
Tetrahymena thermophila
title_short Release of lysosomal enzymes in Tetrahymena: a Ca²⁺-dependent secretory process
title_full Release of lysosomal enzymes in Tetrahymena: a Ca²⁺-dependent secretory process
title_fullStr Release of lysosomal enzymes in Tetrahymena: a Ca²⁺-dependent secretory process
title_full_unstemmed Release of lysosomal enzymes in Tetrahymena: a Ca²⁺-dependent secretory process
title_sort Release of lysosomal enzymes in Tetrahymena: a Ca²⁺-dependent secretory process
dc.creator.none.fl_str_mv Tiedtke, Arno
Rasmussen, Leif
Florin Christensen, Jorge
Florin Christensen, Monica
author Tiedtke, Arno
author_facet Tiedtke, Arno
Rasmussen, Leif
Florin Christensen, Jorge
Florin Christensen, Monica
author_role author
author2 Rasmussen, Leif
Florin Christensen, Jorge
Florin Christensen, Monica
author2_role author
author
author
dc.subject.none.fl_str_mv Biología
Lysosomal enzymes
Secretion
Tetrahymena thermophila
topic Biología
Lysosomal enzymes
Secretion
Tetrahymena thermophila
dc.description.none.fl_txt_mv The ciliate Tetrahymena thermophila releases lysosomal enzymes into nutrient and starvation media. We show here that this process occurs selectively, i.e. without leakage of cytoplasmic components, as indicated by lack of release of isocitrate dehydrogenase, a cytosolic enzyme with high activity in Tetrahymena . The role of intracellular Ca²⁺ in the process was also investigated. The Ca²⁺ ionophore A23187 has strong stimulatory effects on this release. Ionophore stimulation is maximal in the presence of extracellular Ca²⁺ but can occur also in its absence. Quin 2 fluorescence measurements indicate that intracellular Ca²⁺ increases in both cases. Mg²⁺ completely prevents the stimulatory effects of A23187. Ionomycin, another Ca²⁺ ionophore, also stimulates lysosomal enzyme release with a maximal response in the presence of extracellular Ca²⁺ . Measurements of extracellular isocitrate dehydrogenase showed that ionophore-stimulated lysosomal enzyme release can take place without leakage of cytoplasmic components. The observations that divalent cation ionophores stimulate selective lysosomal enzyme release and that this effect is strongest in the presence of external Ca²⁺ indicate that this cation plays a crucial role in the control of this process in Tetrahymena . Together with other observations they support the view that a subpopulation of Tetrahymena lysosomes has properties like those of secretory vesicles.
Centro de Estudios Parasitológicos y de Vectores
description The ciliate Tetrahymena thermophila releases lysosomal enzymes into nutrient and starvation media. We show here that this process occurs selectively, i.e. without leakage of cytoplasmic components, as indicated by lack of release of isocitrate dehydrogenase, a cytosolic enzyme with high activity in Tetrahymena . The role of intracellular Ca²⁺ in the process was also investigated. The Ca²⁺ ionophore A23187 has strong stimulatory effects on this release. Ionophore stimulation is maximal in the presence of extracellular Ca²⁺ but can occur also in its absence. Quin 2 fluorescence measurements indicate that intracellular Ca²⁺ increases in both cases. Mg²⁺ completely prevents the stimulatory effects of A23187. Ionomycin, another Ca²⁺ ionophore, also stimulates lysosomal enzyme release with a maximal response in the presence of extracellular Ca²⁺ . Measurements of extracellular isocitrate dehydrogenase showed that ionophore-stimulated lysosomal enzyme release can take place without leakage of cytoplasmic components. The observations that divalent cation ionophores stimulate selective lysosomal enzyme release and that this effect is strongest in the presence of external Ca²⁺ indicate that this cation plays a crucial role in the control of this process in Tetrahymena . Together with other observations they support the view that a subpopulation of Tetrahymena lysosomes has properties like those of secretory vesicles.
publishDate 1988
dc.date.none.fl_str_mv 1988-05-01
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
Articulo
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://sedici.unlp.edu.ar/handle/10915/142727
url http://sedici.unlp.edu.ar/handle/10915/142727
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/issn/1477-9137
info:eu-repo/semantics/altIdentifier/issn/0021-9533
info:eu-repo/semantics/altIdentifier/doi/10.1242/jcs.90.1.167
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-sa/4.0/
Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)
eu_rights_str_mv openAccess
rights_invalid_str_mv http://creativecommons.org/licenses/by-nc-sa/4.0/
Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)
dc.format.none.fl_str_mv application/pdf
167-171
dc.source.none.fl_str_mv reponame:SEDICI (UNLP)
instname:Universidad Nacional de La Plata
instacron:UNLP
reponame_str SEDICI (UNLP)
collection SEDICI (UNLP)
instname_str Universidad Nacional de La Plata
instacron_str UNLP
institution UNLP
repository.name.fl_str_mv SEDICI (UNLP) - Universidad Nacional de La Plata
repository.mail.fl_str_mv alira@sedici.unlp.edu.ar
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