Question

Can anyone make the main points of this and explain some about them? Thank you

Bioinformatic and biochemical analyses demonstrate that pistol RNAs are members of a novel class of self-cleaving ri- bozymes. Both natural sequence variation and the results of mutational analyses support the secondary structure model, including a proposed pseudoknot formed by nucleotides in the loop of P1 and the junction between P2 and P3. This ar- chitecture, in addition to the array of 10 highly conserved nu- cleotides, is distinct from that of all other known self-cleaving ribozymes Kinetic analyses of a bimolecular pistol ribozyme construct based on a representative from the bacterium L. sphaericus re- veal that pistol ribozymes use multiple catalytic strategies to promote an internal phosphoester transfer reaction with a measured rate constant that exceeds the maximum possible for enzymes that only position the RNA linkage for in-line nucleophilic attack (a) and that fully deprotonate the 240x- ygen nucleophile (y). If the rate constant enhancements gen- erated by increasing pH (Fig. 3D) and increasing Mg concentrations (Fig. 3E) are independent, then the maxi- mum rate constant for the construct tested will be >100 min 1, which greatly exceeds the ay speed limit (Emilsson et al. 2003). Evidence from the use of a phosphorothioate substrate an alog suggests that the ribozyme interacts with one of the nonbridging phosphate oxygen atoms at the cleavage site, but not via inner-sphere coordination with a divalent metal ion at the active site. Indeed, the results of our metal ion-dependent cleavage assay indicate that pistol ribozymes do not require inner-sphere coordination of divalent metal ions anywhere

Answer 1

This paper takes us to high anticipated oneoof newly classes of self cleaving ribozymes.Pistol RNA's are members of distinct class of self cleaving ribozymes.It is recently discovered using bioformatic search strategy.Many hundred pistol ribozymes share harmony.The pistol RNA's are named thus because its secondary structure interpretation's.

It may include 10 highly conserved and many other modestly conserved nucleotides.It is associated with secondary structure charecters which include 3 base pairedsteks and p seudoknot.

From a bacterium lysinibacillus sphaericus a representative pistol ribozyme is found which is used to promote the RNA strand scission.It has a rate constant of -10min(-1)under physiological Mg(2+)and pH conditions.

The reaction via nucleophilic attack of 2-oxygen atomnon the adjecent phosphorous center.

Analysis of metal ion requirements of cleavage reaction and kinetic characteristics shows that the members of ribozyme class uses many catalytic things which is for the promotion of rapid cleavage of RNA.