Maxizymes That Act As A Dimeric Form of Short Ribozymes

DISCOVERY OF MAXIZYMES THAT ACT AS A DIMERIC FORM OF SHORT RIBOZYMES 

We tried to create variants of hammerhead ribozymes with deletions in the stem/loop II region and, fortunately, we found that some shortened forms of hammerhead ribozymes had high cleavage activity that was similar to that of the wild-type parental hammerhead ribozyme (R32 Fig.lA). Moreover, the active species appeared to form dimeric structures with a common stem II (Fig. IB). In the active short ribozymes, the linker sequences that replaced the stem/loop II region were palindromic so that two short ribozymes were capable of forming a dimeric structure with a common stem II. In order to distinguish monomeric forms of conventional minizymes that have extremely low activity from our novel dimers with high-level activity, we 

Since the signals due to imino protons of the maxizyme were broader than those of R32 and since other signals were also detected, it appeared that the homodimeric maxizyme existed in the presence of other contaminating conformers. The NMR spectra of imino protons changed with changes in temperature (Fig.2B and 2C). 

The resonance of an imino proton is observed only if the lifetime of the imino proton is long compared to the rate of exchange with the solvent. As the temperature is increased, base pairs begin to denature and imino protons 

CONSTRUCTION OF tRNAVAL.EMBEDDED MAXIZYMES AND DETECTION OF THE FORMATION OF DIMERIC STRUCTURES BY tRNAVAL EMBEDDED MAXIZYMES 

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