• Wobble pairing describes how tRNA molecules, each carrying an associated amino acid, can bind through their anticodon to multiple different mRNA codons during translation at the ribosome. • Wobble pairing occurs because base pairing between the third position of a mRNA codon and tRNA anticodon does not follow typical base pairing rules.
In 1966, Francis Crick proposed the Wobble Hypothesis to account for this. He postulated that the 5' base on the anticodon, which binds to the 3' base on the mRNA, was not as spatially confined as the other two bases, and could, thus, have non-standard base pairing.
Wobble pairing rules. Watson-Crick base pairs are shown in bold. Parentheses denote bindings that work but will be favoured less. A leading x denotes derivatives (in general) of the base that follows.
Ima smack dat ho wif my Wibble Wobble! A phrase used to deliberately confuse, confound or befuddle a person with little or no grasp of the English language, who is employed in a job or position where the speaking and the comprehension of English is of paramount importance. Gas attendant: What now you want me?
Aside from the obvious necessity of wobble, that our bodies have a limited amount of tRNAs and wobble allows for broad specificity, wobble base pairs have been shown to facilitate many biological functions, most clearly demonstrated in the bacterium Escherichia coli, a model organism.
The four main wobble base pairs are guanine - uracil ( G-U ), hypoxanthine - uracil ( I-U ), hypoxanthine - adenine ( I-A ), and hypoxanthine - cytosine ( I-C ). In order to maintain consistency of nucleic acid nomenclature, "I" is used for hypoxanthine because hypoxanthine is the nucleobase of inosine; nomenclature otherwise follows the names of nucleobases and their corresponding nucleosides (e.g., "G" for both guanine and guanosine – as well as for deoxyguanosine ). The thermodynamic stability of a wobble base pair is comparable to that of a Watson-Crick base pair. Wobble base pairs are fundamental in RNA secondary structure and are critical for the proper translation of the genetic code .
In 1966, Francis Crick proposed the Wobble Hypothesis to account for this. He postulated that the 5' base on the anticodon, which binds to the 3' base on the mRNA, was not as spatially confined as the other two bases and could, thus, have non-standard base pairing.
If the first nucleotide is U or G, the pairing is less specific and in fact two bases can be interchangeably recognized by the tRNA. Inosine displays the true qualities of wobble, in that if that is the first nucleotide in the anticodon then any of three bases in the original codon can be matched with the tRNA.