https://phys.org/news/2020-08-insight-evolution-complex-life-earth.html
Sulfolobus acidocaldarius thrives in geothermal mud pools like this one in New Zealand. Credit: Lancaster University
A novel connection between primordial organisms and complex life has been discovered, as new evidence sheds light on the evolutionary origins of the cell division process that is fundamental to complex life on Earth.
The discovery was made by a cross-disciplinary team of scientists led by Professor Buzz Baum of University College London and Dr. Nick Robinson of Lancaster University.
Their research, published in Science, sheds light on the cell division of the microbe Sulfolobus acidocaldarius, which thrives in acidic hot springs at temperatures of around 75 C. This microbe is classed among the unicellular organisms called archaea that evolved 3.5 billion years ago together with bacteria.
Eukaryotes evolved about 1 billion years later—likely arising from an endosymbiotic event in which an archaeal and bacterial cell merged. The resulting complex cells became a new division of life that now includes the protozoa, fungi, plants and animals.
Now a common regulatory mechanism has been discovered in the cell division of both archaea and eukaryotes after the researchers demonstrated for the first time that the proteasome—sometimes referred to as the waste disposal system of the cell—regulates the cell division in Sulfolobus acidocaldarius by selectively breaking down a specific set of proteins.
The authors report: "This is important because the proteasome has not previously been shown to control the cell division process of archaea."
more at link....................
the paper:
https://science.sciencemag.org/content/369/6504/eaaz2532
The proteasome controls ESCRT-III–mediated cell division in an archaeon
Proteasomal control of division in Archaea
In eukaryotes, proteasome-mediated degradation of cell cycle factors triggers mitotic exit, DNA segregation, and cytokinesis, a process that culminates in abscission dependent on the protein ESCRT-III. By studying cell division in an archaeal relative of eukaryotes, Tarrason Risa et al. identified a role for the proteasome in triggering cytokinesis by an archaeal ESCRT-III homolog. Cell division in this archaeon was driven by stepwise remodeling of a composite ESCRT-III–based division ring, where rapid proteasome-mediated degradation of one ESCRT-III subunit triggered the constriction of the remaining ESCRT-III–based copolymer. These data strengthen the case for the eukaryotic cell division machinery having its origins in Archaea.
Science, this issue p. eaaz2532
Sulfolobus acidocaldarius thrives in geothermal mud pools like this one in New Zealand. Credit: Lancaster University
A novel connection between primordial organisms and complex life has been discovered, as new evidence sheds light on the evolutionary origins of the cell division process that is fundamental to complex life on Earth.
The discovery was made by a cross-disciplinary team of scientists led by Professor Buzz Baum of University College London and Dr. Nick Robinson of Lancaster University.
Their research, published in Science, sheds light on the cell division of the microbe Sulfolobus acidocaldarius, which thrives in acidic hot springs at temperatures of around 75 C. This microbe is classed among the unicellular organisms called archaea that evolved 3.5 billion years ago together with bacteria.
Eukaryotes evolved about 1 billion years later—likely arising from an endosymbiotic event in which an archaeal and bacterial cell merged. The resulting complex cells became a new division of life that now includes the protozoa, fungi, plants and animals.
Now a common regulatory mechanism has been discovered in the cell division of both archaea and eukaryotes after the researchers demonstrated for the first time that the proteasome—sometimes referred to as the waste disposal system of the cell—regulates the cell division in Sulfolobus acidocaldarius by selectively breaking down a specific set of proteins.
The authors report: "This is important because the proteasome has not previously been shown to control the cell division process of archaea."
more at link....................
the paper:
https://science.sciencemag.org/content/369/6504/eaaz2532
The proteasome controls ESCRT-III–mediated cell division in an archaeon
Proteasomal control of division in Archaea
In eukaryotes, proteasome-mediated degradation of cell cycle factors triggers mitotic exit, DNA segregation, and cytokinesis, a process that culminates in abscission dependent on the protein ESCRT-III. By studying cell division in an archaeal relative of eukaryotes, Tarrason Risa et al. identified a role for the proteasome in triggering cytokinesis by an archaeal ESCRT-III homolog. Cell division in this archaeon was driven by stepwise remodeling of a composite ESCRT-III–based division ring, where rapid proteasome-mediated degradation of one ESCRT-III subunit triggered the constriction of the remaining ESCRT-III–based copolymer. These data strengthen the case for the eukaryotic cell division machinery having its origins in Archaea.
Science, this issue p. eaaz2532
