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TOXIN KILLER GENES. "These genetic modules bear surprising resemblance to the basic core of the genetic modules that allow, in cells from multicellular organisms, the regulation of programmed cell death." http://www.nature.com/cdd/journal/v9/n4/full/4400950a.html View in LinkedIn

DEATH HALLMARK. "The evolution of cell death programs as prerequisites of multicellularity. One of the hallmarks of multicellularity is that the individual cellular fate is sacrificed for the benefit of a higher order of life—the organism." http://mcb.berkeley.edu/courses/mcbc245/MCBC245PDFs/Jan31/Huettenbrenner2003.pdf View in LinkedIn

JUDGE, JURY, AND HANGMAN. "The selection for killer genes encoding toxins used in offensive evolutionary arms race against other bacterial species, and the concomitant selection for genes encoding antidotes allowing self-protection is a process that provides the bacteria with both executioners and repressors that can prevent the effect of these executioners." http://www.nature.com/cdd/journal/v9/n4/full/4400950a.html View in LinkedIn

TOXIN-ANTIDOTE STORY. "The reason why bacteria can release a toxin that kill other bacteria without getting killed themselves is that they synthesize an antidote that is not secreted and protects them against the lethal effect of the toxin." http://www.nature.com/cdd/journal/v9/n4/full/4400950a.html View in LinkedIn

CO-EVOLUTION ORIGIN? "Alternatively, the death components in parasitic unicellular eukaryotes might have developed during the host-defense evolution. Notably, even in prokaryotes “apoptotic” features have been described and even examples for shared homologies exist: the TIR is homologous in animals, plants, and bacteria. Toll receptors play a role in the immune defense against parasites and can elicit apoptosis." http://mcb.berkeley.edu/courses/mcbc245/MCBC245PDFs/Jan31/Huettenbrenner2003.pdf View in LinkedIn

"MALE SELF-SACRIFICE”, or apparent male cooperation with female cannibalism, is part of male copulatory behavior in several spider species, and in some insects. One study also reported that males of the spider Argiope aurantia spontaneously die when they copulate." http://www.esciencecentral.org/journals/are-internal-death-promoting-mechanisms-ever-adaptive-2329-9002.1000113.pdf View in LinkedIn

KIN FITNESS. "Pea aphids (Acyrthosiphon pisum) that are parasitized by the Braconid wasp Aphidius ervi drop from the host plant, causing their own death. These insects live in groups of close kin, and their death prevents their body from producing parasites that would then attack their siblings. Death therefore increases the individual’s inclusive fitness, or equivalently, increases the fitness of the kin group." http://www.esciencecentral.org/journals/are-internal-death-promoting-mechanisms-ever-adaptive-2329-9002.1000113.pdf View in LinkedIn

PLANTS. "Plant cells, that have, in addition to mitochondria, another endosymbiotic organelle of cyanobacterial origin, the chloroplast. Do chloroplasts play a role in the regulation of plant programmed cell death? And since an AP-ATPase, a metacaspase and a TIR domain have been identified in cyanobacteria (as in some other bacterial lineages), did plants acquire their putative homologues of the apoptotic machinery through this endosymbiotic process?" http://www.nature.com/cdd/journal/v9/n4/full/4400950a.html View in LinkedIn

CLUSTERING VS ENCODING. "The mitochondria appear to be a locus of clustering of several of the main players in the execution and regulation of programmed cell death. Interestingly, all these players, whether located inside the mitochondria or on its outer surface, are encoded by nuclear genes, and none by mitochondrial genes." (Streamlining of endosymbiont ensured this when the engulfed bacteria transferred most of its genes to the host nucleus). http://www.nature.com/cdd/journal/v9/n4/full/4400950a.html View in LinkedIn

START OF THE STORY. "In favorable environmental conditions, Bacillus subtilis undergoes vegetative growth through symmetrical cell division. In adverse environmental conditions, such as nutrient shortage, Bacillus subtilis undergoes a complex developmental program whose initiation depends, as mentioned above, on cell density and on the concentration of released quorum factors. When initiated, this program begins with a process of asymmetric cell division." http://www.nature.com/cdd/journal/v9/n4/full/4400950a.html View in LinkedIn