Shine-Dalgarno sequence

The Shine -Dalgarno sequence is a sequence of the mRNA in prokaryotes (RBS) is recognized by ribosomes as part of the ribosomal binding site, and thus marks the start of the translation. In 1975 J. Shine and L. Dalgarno discovered the base pairing between mRNA and 16S rRNA in prokaryotes.

The sequence portion of the mRNA that is complementary to the 16S rRNA, ... AGGAGG ... 3'bezeichnet called the Shine -Dalgarno sequence 5 '. The sequence which is complementary to Shine-Dalgarno sequence of 16S rRNA, is sometimes referred to as an anti- Shine-Dalgarno sequence. By means of RNA -protein crosslinking experiments, the proteins were S1 and S21 as those intended to interact with the 3 'end of the 16S rRNA, and are involved in the initiation of translation.

MRNA has upstream of the translation start point ( start codon ), a so called leader sequence, including the 5 ' non- coding region (5'- UTR for the 5' untranslated region ) called. This has believed different than before, a critical function for translation: the portion located 4-14 nucleotides before the start codon, is base-pairing with complementary sequences at the 3'- end of the 16S rRNA and so allows a binding of the 30S subunit of the ribosome.

The length of the complementary section, and its distance from the start codon to determine the stability of the initiation complex.

In eukaryotes, the Kozak sequence takes over the function of the Shine -Dalgarno sequence.