Ribonuclease P (RNase P) is a ribonucleoprotein (RNP) complex that catalyzes the metal-dependent maturation of the 5' end of precursor tRNAs (pre-tRNAs) in all organisms. RNase P is comprised of a catalytic RNA (P RNA), and at least one essential protein (P protein). Although P RNA is the catalytic subunit of the enzyme and is active in the absence of P protein under high salt concentrations in...

Herpes simplex virus 1 (HSV-1), the prototypic member of herpesviruses, employs a virally encoded molecular machine called terminase to package the viral double-stranded DNA (dsDNA) genome into a preformed protein shell. The terminase contains a large subunit that is thought to cleave concatemeric viral DNA during the packaging initiation and completion of each packaging cycle and supply energy...

In a previous study it was shown that RNase P from E. coli cleaves the tRNA-like structure of turnip yellow mosaic virus (TYMV) RNA in vitro (Guerrier-Takada et al. (1988) Cell, 53, 267-272). Cleavage takes place at the 3' side of the loop that crosses the deep groove of the pseudoknot structure present in the aminoacyl acceptor domain. In the present study fragments of TYMV RNA with mutations ...

RNase H enzymes sense the presence of ribonucleotides in the genome and initiate their removal by incising the ribonucleotide-containing strand of an RNA:DNA hybrid. Mycobacterium smegmatis encodes four RNase H enzymes: RnhA, RnhB, RnhC and RnhD. Here, we interrogate the biochemical activity and nucleic acid substrate specificity of RnhA. We report that RnhA (like RnhC characterized previously)...

Secondary structure models for yeast nuclear RNase P RNAs were derived by phylogenetic comparative analysis. RNase P RNA genes from six Saccharomyces species were characterized and compared with the published gene sequences of Saccharomyces cerevisiae (RPR1), Schizosaccharomyces pombe, and Schizosaccharomyces octosporus. The general organization of the Saccharomyces genes were similar: all were...

Triggering and propagating an intracellular innate immune response is essential for control of viral infections. RNase L is a host endoribonuclease and a pivotal component of innate immunity that cleaves viral and cellular RNA within single-stranded loops releasing small structured RNAs with 5'-hydroxyl (5'-OH) and 3'-monophosphoryl (3'-p) groups. In 2007, we reported that RNase L cleaves self ...

RNase E, which is the central component of the multienzyme RNA degradosome, serves as a scaffold for interaction with other enzymes involved in mRNA degradation including the DEAD-box RNA helicase RhlB. Epifluorescence microscopy under live cell conditions shows that RNase E and RhlB are membrane associated, but neither protein forms cytoskeletal-like structures as reported earlier by Taghbalou...

The activated structure of RNase P RNA (PhopRNA) in Pyrococcus horikoshii OT3 was characterized by circular dichroism (CD) and ultraviolet (UV) absorbance spectra. The results suggested that interaction of four RNase P proteins (PhoPop5, PhoRpp21, PhoRpp29, and PhoRpp30) with PhopRNA results in destabilization of base stacking in PhopRNA, whereas the addition of a fifth protein, PhoRpp38, incre...