Nobelprize.org
Back


RNA

Like DNA, the RNA molecule, is built up by nucleotides linked together in a chain. There are some differences though:

- While the DNA consists of two complementary strands attached to one another, forming a double helix. The RNA molecule is single stranded, and folded in various shapes.
- The four bases in the DNA nucleotides are adenine, guanine, thymidine and cytosine. In RNA thymidine is replaced by uracil.
- The sugar in DNA is deoxyribose. In RNA it is ribose.


There are three major types of RNA: 1) mRNA, messenger-RNA, which transfer the information about the aminoacid sequence from the DNA to the protein synthesis. 2) rRNA, ribosomal-RNA, which builds up the ribosome together with proteins. 3) tRNA, transfer-RNA, which transfer aminoacids to the ribosome for protein synthesis.

Back