Did transfer RNA evolve from a ribozyme? An in-silico study

Abstract

Transfer RNA (tRNA) is widely believed to be one of the oldest, if not the oldest nucleic acid on Earth. Concurrently, ribozymes, RNA-only catalysts that perform many of the same functions as present-day protein enzymes, are also thought to be just as ancient. While the position has been posited that tRNA, nature’s chief aminoacylator of amino acids with the assistance of aminoacyl-tRNA synthetase (aaRS) protein enzymes, evolved from a self-aminoacylating ribozyme, no studies have been performed, to the best of this author’s knowledge, searching for nucleotide sequence correlation between the two; such correlation would indicate the conservation of part or all of such a ribozyme in modern-day tRNA. To that end, an in-silico study utilizing several databases was performed to search for a high percentage of highly conserved nucleotide sequences in archaea, believed to be the most ancient of organisms, with very successful results and their implications discussed here.