Ribozymes were first identified by Thomas Cech in 1983 during an experiment attempting to determine the exact protein requirements for mRNA splicing. Experimenters were surprised to find that control samples of an RNA precursor in solution with NTP’s underwent splicing. Even more shocking was that the splicing via the unknown mechanism was site specific, exact, and occurred in the complete absence of proteins.

It was subsequently determined that these RNA molecules, without proteins, catalyze their own splicing and thus are RNA enzymes, or ribozymes. Prior to this discovery, it was thought that only proteins could act enzymatically.

The understanding that RNA could act as both an enzyme and as an information storage molecule shed new light on the evolutionary development of organic macromolecules. It is now hypothesized that the biological world was initially RNA based, before the appearance of DNA and protein.

RNA molecules can catalyze their own replication

RNA molecules can catalyze protein synthesis

Ribosomes (the organelles involved in DNA translation) maintain a significant portion of rRNA which is essential to their functioning

Proteins now dominate the enzymatic niche because of their superior versatility.

DNA was eventually formed via reverse transcription of RNA

RNA had to come first because it’s replication does not require a primer

DNA replaced RNA as storage material because of increased stability.