Year: 2022

ADAPTED GENES. "Since evolution never invents new genes but plays variations on old themes by DNA mutations, it is not surprising, that some of the genes involved in metazoan death pathways apparently have evolved from homologues in unicellular organisms, where they originally had different functions." http://mcb.berkeley.edu/courses/mcbc245/MCBC245PDFs/Jan31/Huettenbrenner2003.pdf View in LinkedIn

BIM-BAD-AND-BAX, ET AL. "Many regulators of apoptosis are located in the mitochondrion or in the mitochondrial inter-membrane space (caspases 2, 3, and 9, cytochrome c, Bcl-2, Bcl-XL, Bad, Bax, Bak, Bim, Smac, HtrA2, AIF). However, we do not find these or homologous components (except HtrA) in contemporary bacteria." http://mcb.berkeley.edu/courses/mcbc245/MCBC245PDFs/Jan31/Huettenbrenner2003.pdf View in LinkedIn

UNICELLULAR programmed cell death and relatives could be the same as organismal death, but many authors thought that this idea did not pass the sniff test. However, surprising new findings have colored this discussion. http://mcb.berkeley.edu/courses/mcbc245/MCBC245PDFs/Jan31/Huettenbrenner2003.pdf View in LinkedIn

NO BRIGHT LINE. "Interestingly some unicellular protozoans have developed a primitive form of non-necrotic cell death themselves, which could mean that the idea of an altruistic death for the benefit of genetically identical cells predated the invention of multicellularity." http://mcb.berkeley.edu/courses/mcbc245/MCBC245PDFs/Jan31/Huettenbrenner2003.pdf View in LinkedIn

"A PARADIGM SHIFT: programmed cell death and apoptosis in single-celled organisms. Programmed cell death in four diverging phylogenic branches of single-celled eukaryotes." http://www.nature.com/cdd/journal/v9/n4/full/4400950a.html View in LinkedIn

FUZZY GREY LINE. "It is important to realize that the frontiers between multicellular organisms and single-celled organisms may not be as stringent as usually believed." http://www.nature.com/cdd/journal/v9/n4/full/4400950a.html View in LinkedIn

LONG AND BROAD. "Currently, there are several possible explanations for the existence of programmed cell death in at least nine single-celled eukaryote organisms belonging to four different lineages that diverged during a still elusive time-frame ranging between two and one billion years ago." http://www.nature.com/cdd/journal/v9/n4/full/4400950a.html View in LinkedIn

ENIGMA. "The death effectors that operate in protozoans are still enigmatic and furthermore there exist also protozoans that cannot undergo an apoptosis-like phenotype. It has to await clarification whether the death machinery was lost by reductive evolution, or whether those species without apparent self destruction mechanisms represent an early phylogenic life form." http://mcb.berkeley.edu/courses/mcbc245/MCBC245PDFs/Jan31/Huettenbrenner2003.pdf 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

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