Genome complexity; garbage removal (Introduction)

by David Turell , Thursday, February 07, 2013, 14:48 (4309 days ago) @ David Turell

Cells make proteins that must be destroyed; cells also make RNA's that guide processes and then must be destroyed or the cell will become so stuffed it won't function. There is a proteosome for proteins and an exosome for RNAs:-"The structure of this complex allowed the scientists to understand how the exosome works. "It is quite an elaborate machine: the exosome complex forms a hollow barrel formed by nine different proteins through which RNA molecules are threaded to reach a tenth protein, the catalytic subunit that then shreds the RNA into pieces," says Debora Makino. The barrel is essential for this process because it helps to unwind the RNA and prepares it for shredding. "Cells lacking any of the ten proteins do not survive and this shows that not only the catalytic subunit but also the entire barrel is critical for the function of the exosome," Makino explains." (my bold)-http://www.sciencedaily.com/releases/2013/02/130204094606.htm-This fits Behe's definition of 'irreducable complexity', a structure that cannot have evolved one protein step at a time.-Further these processes are found in Archaea and other bacteria, again showing how complex the original living cells had to be.