David's theory of evolution: God's correction of errors (Evolution)

by David Turell @, Sunday, August 02, 2020, 20:40 (58 days ago) @ David Turell

Here is the mechanism of editors correcting DNA errors:

https://www.sciencedaily.com/releases/2020/07/200716123002.htm

"New research shows how proofreading proteins prevent DNA replication errors by creating an immobile structure that calls more proteins to the site to repair the error. This structure could also prevent the mismatched region from being ''packed'' back into the cell during division.

"On the DNA assembly line, two proofreading proteins work together as an emergency stop button to prevent replication errors. New research from North Carolina State University and the University of North Carolina at Chapel Hill shows how these proteins -- MutL and MutS -- prevent DNA replication errors by creating an immobile structure that calls more proteins to the site to repair the error. This structure could also prevent the mismatched region from being "packed" back into the cell during division.

***

"The nucleotides are a correct match most of the time, but occasionally -- about one time in 10 million -- there is a mismatch.

"'Although mismatches are rare, the human genome contains approximately six billion nucleotides in every cell, resulting in approximately 600 errors per cell, and the human body consists of more than 37 trillion cells," says Dorothy Erie, chemistry professor at UNC-Chapel Hill,

***

"A pair of proteins known as MutS and MutL work together to initiate repair of these mismatches. MutS slides along the newly created side of the DNA strand after it's replicated, proofreading it. When it finds a mismatch, it locks into place at the site of the error and recruits MutL to come and join it. MutL marks the newly formed DNA strand as defective and signals a different protein to gobble up the portion of the DNA containing the error. Then the nucleotide matching starts over, filling the gap again. The entire process reduces replication errors around a thousand-fold,

***

"...the researchers found that MutL "freezes" MutS in place at the site of the mismatch, forming a stable complex that stays in that vicinity until repair can take place. The complex appears to reel in the DNA around the mismatch as well, marking and protecting the DNA region until repair can occur.

"'Due to the mobility of these proteins, current thinking envisioned MutS and MutL sliding freely along the mismatched strand, rather than stopping," Weninger says. "This work demonstrates that the process is different than previously thought.

"'Additionally, the complex's interaction with the strand effectively stops any other processes until repair takes place. So the defective DNA strand cannot be repacked into a chromosome and then carried forward through cell division.'"

Comment: Here again we see a corrective mechanism designed by God to correct expected errors. My reasoning is simple as before. The corrective design must be present when each species appears or it would not survive repetitive errors that would occur. It is not a matter of a weak God but one who fully understands the problems attendant with living biochemical high-speed functions.


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