2007 年 35 巻 4 号 p. 104-109
Genetic code gives a relationship between a triplet base sequence on RNA and an amino acid in the corresponding protein required for effective function in organisms. Accurate knowledge about the genetic code, including the origin and evolutionary process of it, would be helpful to understand the origin of life. In fact, we have previously provided several hypotheses on the origins of genes, the genetic code and proteins, which lead us to elucidation of the origin of life. In this review, I introduce a new scenario from accumulation of simple [GADV]-amino acids and formation of [GADV]-protein world to the emergence of life, or [GADV]-protein world hypothesis, which was presented by us. GADV means four amino acids, Gly[G], Ala[A], Asp[D] and Val[V], which are described by one-letter representation. In the last section of this review, I also point out several weak points of other theories on the origin of life, such as “RNA world hypothesis” and “protein-RNA world theory”.
