Solid Phase Chemical Synthesis of RNA.

Solid phase oligonucleotide synthesis enables the generation of various biologically relevant RNAs. These include RNA sequences 20-80 nucleotides in length, such as microRNA (miRNA), small interfering RNA (siRNA), self-amplifying RNA (saRNA), and RNA aptamers. Modern advances in RNA chemical synthesis have also produced longer RNA sequences (≥100 nucleotides), such as guide RNA (gRNA), messenger RNA (mRNA), riboswitches, and ribozymes. Further, the introduction of orthogonal protecting and reactive groups allows for the chemical synthesis of branch RNA as mimics of intronic RNA lariats. Here, we describe a solid phase chemical synthesis protocol based on t-butydimethylsilyl (TBDMS) phosphoramidite chemistry to produce native or branched RNA suitable for structural, functional, or biological studies.