Synthesis and binding properties of a homopyrimidine 2',5'-linked xylose nucleic acid (2',5'-XNA).

The synthesis and hybridization properties of pyrimidine 2',5'-RNA and 2',5'-Xylose Nucleic Acid (2',5'-XNA) are described.

Branchpoint sugar stereochemistry determines the hydrolytic susceptibility of branched RNA fragments by the yeast debranching enzyme (YDBR).

A series of branched RNAs (Y-shaped) related to yeast pre-mRNA splicing intermediates were synthesized incorporating both natural (i.e., ribose) and non-natural (i.e., arabinose, xylose and acyclic nucleoside) branchpoints in order to examine the effect of sugar conformation and phosphodiester configuration on yDBR hydrolytic efficiency. The results indicate that 2'-phosphodiester scission with yDBR occurs only with a cis-arrangement of phosphate groups at the branchpoint (i.e., ribose) thereby discriminating between all other configurations.