Self-splicing, RNA

Like self-splicing RNAs, which excise introns from their chains, a few proteins are able to splice out segments of their own chains as inteins. The surrounding protein sequences can be referred to as exteins. Over 100 self-splicing proteins are known. They are found in all kingdoms of life.a The inteins, which are excised, are typically 50 kDa in size but range from 360 to over 500 residues. 

Kruger, K., Grabowski, P.J., Zaug, A.J., Sands, J., Gottschling, D.E. and Cech, T.R. (1982) Self-splicing RNA autoexcision and autocyclization of the ribosomal RNA intervening sequence of Tetrahymena. Cell, 31,147-157. 

T. R. Cech, Self-splicing RNA autoexcision and autocyclization of the ribosomal RNA intervening sequence of Tetrahymena, Cell 1982, 31, 147-157. 

K. Kruger, P.J. Grabowski, A.J. Zaug, J. Sands, D.E. Gottschling, T.R. Chech, Self-Splicing RNA Autoexcision and Autocyclization of the Ribosomal RNA Intervening Sequence of Tetrahymena , Cell, 31, 147 (1982)... 

Positive control by activator proteins 1643 Self-splicing RNA... 

A, although models suggest that in this case an adjacent attack may be involved. These results not only suggest a mechanism for the toxicity of lead, but may be relevant to the requirement of self-splicing RNA for the presence of metal ions. 

Describe the discovery of self-splicing RNA and outline the reactions that occur during the conversion of a ribosomal RNA (rRNA) precursor from Tetrahymena into the spliced, mature rRNA and other linear and circular products. Explain the role of guanosine or a guanylyl nucleotide in the self-splicing reaction. 

Brown, R. S., B. E. Hingerty, J. C. Dewan, et al. 1983. Pb(ll)-Catalysed Cleavage of the Sugar-Phosphate Backbone of Yeast tRNAPhe—Implications for Lead Toxicity and Self Splicing RNA. Nature 303 543-546. 

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