Structural basis of ribosomal 30S subunit degradation by RNase R. (https://pubmed.ncbi.nlm.nih.gov/38326618/)

These scientists wanted to understand how cells break down and get rid of a part called the ribosome. The ribosome is like a tiny machine in the cell that helps make proteins, which are important for many things in our body.

The scientists studied a specific process called protein synthesis, which is when the cell uses energy to make proteins. They focused on a part of the ribosome called the 30S subunit. They discovered that there is a special enzyme called RNase R that helps break down the 30S subunit when it is no longer needed.

To understand how RNase R works, the scientists used special techniques to look at the structure of the ribosome and the enzyme. They found that RNase R first attaches to a specific part of the ribosome called the 30S platform. This helps the enzyme start breaking down the ribosome by removing important parts that are no longer needed.

But then, the scientists discovered that the enzyme faces a problem when it reaches another part of the ribosome called the neck region. This problem is like a roadblock that stops the enzyme from continuing to break down the ribosome. However, the scientists observed that the ribosome can change its shape to overcome this roadblock. When the ribosome changes its shape, it loses some of its parts.

The enzyme, RNase R, follows the ribosome and moves to another part called the decoding site. It does this by using a special part of itself called the N-terminal helix-turn-helix domain as an anchor. This means that the enzyme can attach itself to the ribosome in a different place.

The scientists also did experiments in the lab to test how well RNase R can break down the ribosome. They found that the ribosome changing its shape is a big challenge for the enzyme, but the enzyme is still able to break down the ribosome completely.

Overall, this study helps us understand how cells get rid of the ribosome when it is no longer needed. The enzyme RNase R plays an important role in this process, and it uses a dynamic mechanism to target and break down the ribosome.

Dimitrova-Paternoga L., Kasvandik S., Beckert B., Granneman S., Tenson T., Wilson DN., Paternoga H. Structural basis of ribosomal 30S subunit degradation by RNase R. Nature. 2024 Feb 7. doi: 10.1038/s41586-024-07027-6.