Search results
Results from the WOW.Com Content Network
Ribonucleic acid (RNA) is a polymeric molecule that is essential for most biological functions, either by performing the function itself (non-coding RNA) or by forming a template for the production of proteins (messenger RNA). RNA and deoxyribonucleic acid (DNA) are nucleic acids.
All living cells contain both DNA and RNA (except some cells such as mature red blood cells), while viruses contain either DNA or RNA, but usually not both. [15] The basic component of biological nucleic acids is the nucleotide, each of which contains a pentose sugar (ribose or deoxyribose), a phosphate group, and a nucleobase. [16]
This is the single largest group of RNA viruses [23] and has been organized by the ICTV into the phyla Kitrinoviricota, Lenarviricota, and Pisuviricota in the kingdom Orthornavirae and realm Riboviria. [24] Positive-strand RNA viruses can also be classified based on the RNA-dependent RNA polymerase. Three groups have been recognised: [25]
Small RNA that is activated by SgrR in Escherichia coli during glucose-phosphate stress shRNA: short hairpin RNA - siRNA: small interfering RNA - SL RNA spliced leader RNA multiple families: SmY RNA: mRNA trans-splicing RF01844: Small nuclear RNAs found in some species of nematode worms, thought to be involved in mRNA trans-splicing snoRNA ...
A tetraloop is a four-base pairs hairpin RNA structure. There are three common families of tetraloop in ribosomal RNA: UNCG, GNRA, and CUUG (N is one of the four nucleotides and R is a purine). UNCG is the most stable tetraloop. [9] Pseudoknot is an RNA secondary structure first identified in turnip yellow mosaic virus. [10]
Ribosomal RNA characteristics are important in evolution, thus taxonomy and medicine. rRNA is one of only a few gene products present in all cells. [45] For this reason, genes that encode the rRNA are sequenced to identify an organism's taxonomic group, calculate related groups, and estimate rates of species divergence. [68]
Nucleic acids were first discovered in 1868 by Friedrich Miescher, [13] and by 1939, RNA had been implicated in protein synthesis. [14] Two decades later, Francis Crick predicted a functional RNA component which mediated translation; he reasoned that RNA is better suited to base-pair with an mRNA transcript than a pure polypeptide.
In eukaryotes, three kinds of RNA—rRNA, tRNA, and mRNA—are produced based on the activity of three distinct RNA polymerases, whereas, in prokaryotes, only one RNA polymerase exists to create all kinds of RNA molecules. [3] RNA polymerase II of eukaryotes transcribes the primary transcript, a transcript destined to be processed into mRNA ...