Biochemical controls: proper delivery of proteins (Introduction)

by David Turell , Tuesday, June 25, 2024, 19:43 (149 days ago) @ David Turell

Cells constantly produce proteins with controlled delivery:

https://phys.org/news/2024-06-reveals-enzyme-hitches-trna.html

"Imagine your body as a highly organized factory where workers tirelessly assemble proteins around the clock. These proteins are the machines and scaffolds that make up your body and are essential for various functions. In this factory, special delivery trucks called transfer RNA (tRNA) deliver amino acids—the crucial building blocks of proteins—to the protein-making machinery—ribosomes.

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"The team studied tRNA modification enzymes—a type of specialized molecular workers, which can "customize" these tRNA delivery trucks. They make specific changes or additions to the tRNA structure, which enhance the efficiency and accuracy of the protein-building process. This ensures that the tRNA trucks are optimized and tailored for their respective tasks, leading to a more reliable and precise production of proteins.

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"In the case of the METTL6 tRNA modification enzyme, the researchers figured out that it does not act on its own, but interacts with another enzyme—a "tRNA synthetase."

"In the analogy above, tRNA synthetases are the workers responsible for loading the tRNA delivery vehicles and ensuring that the right amino acids are loaded onto these trucks. Each tRNA delivery truck carries a specific code or pattern that matches with a code on the construction site. tRNA synthetases are very smart enzymes that can read the nucleotide code of the tRNA trucks and then find and load the correct amino acid that matches the code.

"The scientists found that the tRNA modification enzyme METTL6 on its own is not particularly specific and not very efficient at doing its job. Instead, METTL6 takes the hand of its smart friend—the serine tRNA synthetase. This tRNA synthetase specifically binds tRNAs that carry the code for an amino acid called serine.

"When the serine tRNA is bound to the serine tRNA synthetase enzyme, it is much easier to distinguish from other tRNAs. You could think of serine tRNA synthetase as a very smart friend that helps METTL6 figure out which tRNA to modify. The authors of the study believe this friendship is the first known example of a tRNA-modifying enzyme using a tRNA synthetase as a recognition factor."

Comment: this article raises the usual question. How does a blind natural process find exact protein components? What is more likely is a designer at work.