Popis: |
The origin of genes is one of the most enigmatic events in the origin of life. It has been suggested that noncoding (nc) RNA was probably a precursor in the formation of the first polypeptide, and also at the origin of the first manifestation of life and genes. ncRNAs are also becoming central for understanding gene expression and silencing. Indeed, before the discovery of ncRNAs, proteins were viewed as the major molecules in the regulation of gene expression and gene silencing; however, recent findings suggest that ncRNA also plays an important role in gene expression. Reverse transcription of RNA viruses and their integration into the genome of eukaryotes and also their relationship with the ncRNA suggest that their origin is basal in genome evolution, and also probably constitute the first mechanism of gene regulation. I am to review the different roles of ncRNAs in the framework of gene evolution, as well as the importance of ncRNAs and viruses in the epigenesis and in the non-Mendelian model of heredity and evolution. |