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The RNA world hypothesis places RNA at center-stage when life originated. The RNA world hypothesis is supported by the observations that ribosomes are ribozymes: [120] [121] the catalytic site is composed of RNA, and proteins hold no major structural role and are of peripheral functional importance. This was confirmed with the deciphering of ...
Spiegelman's Monster is an RNA chain of only 218 nucleotides that is able to be reproduced by the RNA replication enzyme RNA-dependent RNA polymerase, also called RNA replicase. It is named after its creator, Sol Spiegelman , of the University of Illinois at Urbana-Champaign who first described it in 1965.
The nearly universal genetic code preserves some evidence for the RNA world. For instance, recent studies of transfer RNAs, the enzymes that charge them with amino acids (the first step in protein synthesis) and the way these components recognize and exploit the genetic code, have been used to suggest that the universal genetic code emerged ...
This realization led to the RNA World Hypothesis, a proposal that RNA may have played a critical role in prebiotic evolution at a time before the molecules with more specialized functions (DNA and proteins) came to dominate biological information coding and catalysis.
In the eocyte hypothesis, the organism at the root of all eocytes may have been a ribocyte of the RNA-world. For cellular DNA and DNA handling, an "out of virus" scenario has been proposed: storing genetic information in DNA may have been an innovation performed by viruses and later handed over to ribocytes twice, once transforming them into bacteria and once transforming them into archaea.
Woese's dogma is a principle of evolutionary biology first put forth by biophysicist Carl Woese in 1977. It states that the evolution of ribosomal RNA was a necessary precursor to the evolution of modern life forms. [1]
In line with the RNA world hypothesis, transfer RNA molecules appear to have evolved before modern aminoacyl-tRNA synthetases, so the latter cannot be part of the explanation of its patterns. [80] A hypothetical randomly evolved genetic code further motivates a biochemical or evolutionary model for its origin.
The RNA Ligase ribozyme was the first of several types of synthetic ribozymes produced by in vitro evolution and selection techniques. They are an important class of ribozymes because they catalyze the assembly of RNA fragments into phosphodiester RNA polymers, a reaction required of all extant nucleic acid polymerases and thought to be ...