Functional reconstitution of RNase P activity from a plastid RNA subunit and a cyanobacterial protein subunit

Pascual, Alberto; Vioque, Agustı́n

doi:10.1016/s0014-5793(98)01621-4

Cited by 19 publications

(10 citation statements)

References 18 publications

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“…The analysis of organellar P-RNAs has been complicated by the patchy occurrence of the rnpB gene, both in chloroplast and mitochondrial DNAs (mtDNAs). The chloroplast-encoded P-RNA of Cyanophora paradoxa folds into a Cyanobacteria-like secondary structure (in agreement with the cyanobacterial origin of chloroplasts) and is essential for RNase P activity (Baum et al 1996;Pascual and Vioque 1999). Chloroplast DNA (cpDNA)-encoded rnpB genes have been found only in the green alga Nephroselmis olivacea (Turmel et al 1999), the red algae Porphyra purpurea (Reith and Munholland 1995), and Cyanidium caldarium.…”

Section: Introductionmentioning

confidence: 59%

Mitochondrial RNase P RNAs in ascomycete fungi: Lineage-specific variations in RNA secondary structure

Seif¹,

Forget²,

Martín³

et al. 2003

RNA

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The RNA subunit of mitochondrial RNase P (mtP-RNA) is encoded by a mitochondrial gene (rnpB) in several ascomycete fungi and in the protists Reclinomonas americana and Nephroselmis olivacea. By searching for universally conserved structural elements, we have identified previously unknown rnpB genes in the mitochondrial DNAs (mtDNAs) of two fission yeasts, Schizosaccharomyces pombe and Schizosaccharomyces octosporus; in the budding yeast Pichia canadensis; and in the archiascomycete Taphrina deformans. The expression of mtP-RNAs of the predicted size was experimentally confirmed in the two fission yeasts, and their precise 5 and 3 ends were determined by sequencing of cDNAs generated from circularized mtP-RNAs. Comparative RNA secondary structure modeling shows that in contrast to mtP-RNAs of the two protists R. americana and N. olivacea, those of ascomycete fungi all have highly reduced secondary structures. In certain budding yeasts, such as Saccharomycopsis fibuligera, we find only the two most conserved pairings, P1 and P4. A P18 pairing is conserved in Saccharomyces cerevisiae and its close relatives, whereas nearly half of the minimum bacterial consensus structure is retained in the RNAs of fission yeasts, Aspergillus nidulans and Taphrina deformans. The evolutionary implications of the reduction of mtP-RNA structures in ascomycetes will be discussed.

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Section: Introductionmentioning

confidence: 59%

Mitochondrial RNase P RNAs in ascomycete fungi: Lineage-specific variations in RNA secondary structure

Seif¹,

Forget²,

Martín³

et al. 2003

RNA

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“…Although the RNA subunit alone is not catalytically active (69,70), it is essential for RNase P activity, as indicated by the sensitivity of the holoenzyme to micrococcal nuclease treatment (27). The protein subunits of cyanelle RNase P have yet to be identified, but they constitute about 80% of the mass of the holoenzyme (68), an extensive protein content.…”

Section: Chloroplast Rnase Pmentioning

confidence: 99%

Eukaryotic Ribonuclease P: A Plurality of Ribonucleoprotein Enzymes

Xiao

Scott

Fierke³

et al. 2002

Annu. Rev. Biochem.

127

106

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Ribonuclease P (RNase P) is an essential endonuclease that acts early in the tRNA biogenesis pathway. This enzyme catalyzes cleavage of the leader sequence of precursor tRNAs (pre-tRNAs), generating the mature 5′ end of tRNAs. RNase P activities have been identified in Bacteria, Archaea, and Eucarya, as well as organelles. Most forms of RNase P are ribonucleoproteins, i.e. they consist of an essential RNA subunit and protein subunits, although the composition of the enzyme in mitochondria and chloroplasts is still under debate. The recent purification of the eukaryotic nuclear RNase P has demonstrated a significantly larger protein content compared to the bacterial enzyme. Moreover, emerging evidence suggests that the eukaryotic RNase P has evolved into at least two related nuclear enzymes with distinct functions, RNase P and RNase MRP. Here we review current information on RNase P, with emphasis on the composition, structure, and functions of the eukaryotic nuclear holoenzyme, and its relationship with RNase MRP.

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“…The genome of the chloroplasts of some algae codes for a bacterialike RNase P RNA gene (35)(36)(37). However, in the only case studied (Cyanophora), the coded RNA is not active in the absence of protein (38,39), but it was possible to reconstitute a functional holoenzyme with a protein subunit from cyanobacteria (39) and the plastidencoded RNA.…”

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confidence: 99%

RNase P: Variations and Uses

Gopalan¹,

Vioque²,

Altman³

2002

Journal of Biological Chemistry

108

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This essay will bring to date a picture of the properties of RNase P from several organisms and a summary of how this enzyme can be used to decrease specific gene expression. Current details of how the enzyme works and other features governing its reaction are reviewed elsewhere (1-3).RNase P is responsible for generating the mature 5Ј-end of tRNAs by a single endonucleolytic cleavage of their precursors. It is an essential, ubiquitous enzyme present in all cells and cellular compartments that synthesize tRNA: bacterial cells, eukaryotic nuclei, mitochondria, and chloroplasts. The essential function in vivo of RNase P has been demonstrated in those systems amenable to genetic analysis such as bacteria (4) and yeast nuclei (5) and mitochondria (6, 7). All known RNase P enzymes are ribonucleoproteins and contain an RNA subunit essential for catalysis with the possible exception of RNase P in some plant chloroplasts and trypanosome mitochondria (8, 9).The chemical mechanism of RNase P involves essential divalent metal ions (2) and is thought to be an in-line S N 2 displacement reaction (1). The endonucleolytic cleavage generates 5Ј-phosphate and 3Ј-hydroxyl end groups in the products. For our purposes, the way in which the enzyme recognizes substrates is an important feature of its ability to lower the amount of any particular RNA and expression inside cells. Natural substrates can be reduced to two oligonucleotides, which when hydrogen bonded together (Fig. 1) resemble sufficiently the essential features of a substrate so that one of the oligonucleotides, the target RNA (i.e. any RNA inside the cell), is cleaved efficiently by the enzyme and inactivated. This important aspect of RNase P revolves entirely around its substrate recognition mechanism and does not depend on the fact that there is an RNA subunit in the enzyme.The RNA Subunit of RNase P The RNA component of RNase P from bacteria is encoded by the rnpB gene and varies in length between about 350 and 450 nucleotides (10). There is little sequence similarity among the 300 or so bacterial sequences except for a few short segments. Phylogenetic covariation analysis of the large data set has allowed the precise definition of the secondary structure and the identification of several tertiary interactions (11)(12)(13)(14)(15). This RNA from bacteria can be divided into two distinct structural classes: type A, represented by Escherichia coli, which is the ancestral type found in most bacteria (the RNA subunit of the enzyme from E. coli is called M1 RNA and is referred to by that name herein), and type B, represented by Bacillus subtilis, which is found in the low GC content Grampositive bacteria (16). An intermediate structure (type C) is found in green non-sulfur bacteria (12). Despite differences in the secondary structure organization of type A and type B RNAs, both RNAs can be modeled into a similar three-dimensional structure with the evolutionarily conserved nucleotides placed in nearly identical positions (16). These computer-aided modeling efforts illustr...

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Functional reconstitution of RNase P activity from a plastid RNA subunit and a cyanobacterial protein subunit

Cited by 19 publications

References 18 publications

Mitochondrial RNase P RNAs in ascomycete fungi: Lineage-specific variations in RNA secondary structure

Mitochondrial RNase P RNAs in ascomycete fungi: Lineage-specific variations in RNA secondary structure

Eukaryotic Ribonuclease P: A Plurality of Ribonucleoprotein Enzymes

RNase P: Variations and Uses

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