Q. What is self-catalytic RNAs?

Ribozymes -Term 'ribozyme' was initially suggested by Thomas R. Cech, Nobel Prize winning biochemist, who discovered this class of RNA molecules. A ribozyme is an RNA molecule which may catalyze a biochemical reaction. Before discovery of ribozymes, it was generally presumed that protein enzymes were only class of biological catalysts. Cech's discovery was truly revolutionary in upsetting this dogma. First ribozymes discovered were introns which could catalyze their own splicing, that is a special type of intron within a pre-RNA molecule was found to catalyze all steps required for intron removal and joining of exons together at the biologically correct site.

Ribozymes with other kinds of biological activity have since been discovered. One intriguing potential ribozyme is peptidyl transferase activity of ribosome. Many believe that peptide bond formation is catalyzed by23S ribosomal RNA, a potential ribozyme, instead of ribosomal proteins.