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2008 Discovery that manganese-dependent ribozyme occurs naturally in the 3'-UTR of Vg1 and beta-actin mRNAs
The Vg1 ribozyme is the smallest ribozyme to be identified which is a manganese-dependent ribozyme. The Vg1 ribozyme catalyzes a first-order reaction where its mechanism of cleavage is similar to the manganese ribozyme present in Tetrahymena group I introns. CAUTION: We not aware of any publications confirming these observations. It is highly probable that CoTC is not a nucleolytic ribozyme.
 A manganese-dependent ribozyme in the 3'-untranslated region of Xenopus Vg1 mRNA.
Kolev, N. G., E. I. Hartland and P. W. Huber
Nucleic Acids Res 36(17): 5530-5539.(2008)