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Liña 220:
 
== Nos mofos mucosos ==
 
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The socialO [[Slimemofo mould|slime moldmucoso]] social ''[[Dictyostelium discoideum]]'' hasten thea peculiaritypeculiaridade ofde eitheradoptar adoptingun acomportamento predatoryde tipo [[amoeboidameba|amoebaameboide]]-like behaviorpredador inna itssúa [[Microorganism|unicellular]]forma formunicelular orou coalescingcoalescer intonunha aforma mobilereptante [[slug]]-likemóbil formque whendispersa dispersing theas [[sporeespora]]s that will giveque birthdarán tolugar theá nextseguinte [[generationxeración]].<ref>
{{cite journal
|vauthors=Crespi B, Springer S |year = 2003
Liña 231:
}}</ref>
 
A forma reptante forma un talo que sostén na parte superior as células formadoras de esporas. O talo está composto de células mortas que sufriron un tipo de MCP que comparte moitas características dunha morte celular autofáxica: fórmansed vacúolos masivos dentro das células, e prodúcese certo grao de condensación da [[cromatina]], pero non fragmentación do [[ADN]].<ref>
The stalk is composed of dead cells that have undergone a type of PCD that shares many features of an autophagic cell-death: massive vacuoles forming inside cells, a degree of [[chromatin]] condensation, but no [[Restriction digest|DNA fragmentation]].<ref>
{{cite journal
|vauthors=Levraud JP, Adam M, Luciani MF, de Chastellier C, Blanton RL, Golstein P |year = 2003
Liña 240:
|pmc = 2172757
|doi = 10.1083/jcb.200212104
}}</ref> O papel estrutural dos residuos que deixan as células mortas lembra os produtos da MCP en tecidos de plantas.
}}</ref> The structural role of the residues left by the dead cells is reminiscent of the products of PCD in plant tissue.
 
''D. discoideum'' é un mofo mucoso, parte dunha póla evolutiva que se cre que se esgallou dos seus antepasados eucariotas hai uns mil millóns de anos antes do presente. Parece que emerxeron despois de que se diferenciasen os antepasados das [[Viridiplantae|plantas verdes]] e os dos [[fungo (bioloxía)|fungos]] e [[animal|animais]]. Pero, ademais dos seus lugares na [[árbore filoxenética]], o feito de que a MCP estea presengte tamén nun organismo modesto e simple, de só seis [[cromosoma]]s como ''D. discoideum'' ten unha importancia adicional: permite o estudo da vía da MCP do desenvolvemento que non depende das [[caspase]]s característica da apoptose.<ref>
''D. discoideum'' is a slime mold, part of a branch that might have emerged from [[Eukaryote|eukaryotic]] ancestors about a [[Timeline of evolution|billion years]] before the present. It seems that they emerged after the ancestors of [[Viridiplantae|green plants]] and the ancestors of [[fungi]] and animals had differentiated. But, in addition to their place in the evolutionary [[Phylogenetic tree|tree]], the fact that PCD has been observed in the humble, simple, six-[[chromosome]] ''D. discoideum'' has additional significance: It permits the study of a developmental PCD path that does not depend on caspases characteristic of apoptosis.<ref>
{{cite journal
|vauthors=Roisin-Bouffay C, Luciani MF, Klein G, Levraud JP, Adam M, Golstein P |year = 2004
Liña 253:
 
== Orixe evolutiva ==
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The occurrence of programmed cell death in [[protist]]s is possible,<ref>{{cite journal | last1 = Deponte | first1 = M | year = 2008 | title = Programmed cell death in protists | url = http://www.sciencedirect.com/science/article/pii/S0167488908000384 | journal = Biochimica et Biophysica Acta (BBA) - Molecular Cell Research | volume = 1783 | issue = 7| pages = 1396–1405 | doi=10.1016/j.bbamcr.2008.01.018}}</ref> but it remains controversial. Some categorize death in those organisms as unregulated, by necrosis or incidental death.<ref>{{cite journal | last1 = Proto | first1 = W. R. | last2 = Coombs | first2 = G. H. | last3 = Mottram | first3 = J. C. | year = 2012 | title = Cell death in parasitic protozoa: regulated or incidental? | url = http://www.gla.ac.uk/media/media_248886_en.pdf | format = PDF | journal = Nature Reviews Microbiology | volume = 11 | issue = 1| pages = 58–66 | doi=10.1038/nrmicro2929}}</ref>
 
Liña 263 ⟶ 264:
Mitochondriate eukaryotic cells live poised between [[life]] and death, because mitochondria still retain their repertoire of [[molecule]]s that can trigger cell suicide.<ref>{{cite journal|vauthors=Chiarugi A, Moskowitz MA |year=2002|title=Cell biology. PARP-1--a perpetrator of apoptotic cell death?|journal=[[Science (journal)|Science]]|volume=297|issue=5579|pages=200–1|pmid= 12114611|doi=10.1126/science.1074592}}</ref> This process has now been evolved to happen only when programmed.{{Citation needed|date=April 2008}} Given certain [[Cell signaling|signals]] to cells (such as feedback from neighbors, stress or [[DNA repair|DNA damage]]), mitochondria release [[caspase]] activators that trigger the cell-death-inducing [[Biochemistry|biochemical]] cascade. As such, the cell suicide [[Reaction mechanism|mechanism]] is now crucial to all of our lives.
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== Importancia clínica ==
 
Traído desde «https://gl.wikipedia.org/wiki/Morte_celular_programada»