Novel DNA and RNA elements

Impressive advances in the field of synthetic biology go hand in hand with the discovery, design, and use of novel DNA and RNA elements. Efficient synthesis of large oligonucleotides and double-stranded DNA parts, chip-based synthesis of DNA libraries, and a detailed understanding of fundamental biological mechanisms and increased capacities in bioinformatics enable new findings and applications. In this chapter, reengineered and model-based designed DNA parts such as promoters, terminators, and aptamers, which can be used for controlled gene expression, are discussed. Furthermore, recent advances in the RNA world concerning small RNAs, ribozymes, and riboswitches and novel applications of synthetic nucleotide sequences in the form of DNA walkers and DNA machines are emphasized. The knowledge and experiences gained in the investigations of large numbers of natural and novel DNA and RNA parts have built the foundation for the design of new functions of polynucleotides and model-based regulation of gene and pathway expression.