Sequence and functional characterization of RNase P RNA from the chl a/b containing cyanobacterium Prochlorothrix hollandica

Abstract
Only a few complete sequences and very limited functional data are available for the catalytic RNA component of cyanobacterial RNase P. The RNase P RNA from the chl a/b containing cyanobacterium Prochlorothrix hollandica belongs to a rarely found structural subtype with an extended P15/16 domain. We have established conditions for optimal in vitro ribozyme activity, and determined the kinetic parameters for cleavage of pre-tRNATyr. Analysis of pre-tRNA mutants revealed that the T-stem sequence only plays a modulating role, whereas the CCA end is essential for efficient product formation.