Identification and Analysis of Small Nucleolar RNAs by Real-Time Quantitative PCR.

One of the greatest scientific achievements of the twenty-first century is the completion of The Human Genome Project (HGP). Thereafter, we came to know that the human genome codes nearly 2% for making proteins and thus named as coding genes, suggesting the rest of the genome as noncoding or junk. However, research in the past two decades has shown and established that noncoding RNAs are major contributors of regulating and modulating the various function of cells as well as tissues. Noncoding RNAs can be classified as basis of their sizes in two categories, long noncoding RNAs (>200 nt) and small noncoding RNAs (<200 nt). Small nucleolar RNAs (snoRNAs) are part of the small noncoding RNA family and primarily reside inside the nucleus of eukaryotes. Sno RNAs can be divided into two major categories based on their distinguished structure and function; these are C/D box and HACA box snoRNAs. They participate in the posttranscriptional modifications on ribosomal RNAs (r-RNAs), transfer RNAs (t-RNAs), messenger RNAs (m-RNAs), and small nuclear RNAs (snRNAs). Sno RNAs act as guide RNAs to modify other noncoding RNAs by pseudouridylation or 2'O ribomethylation. We discussed in this protocol about one of the widely used techniques for detection and analysis of snoRNAs, i.e., real-time quantitative PCR (RT-qPCR).