7OG5

RNA-free Ribonuclease P from Halorhodospira halophila

Summary for 7OG5

• Entry DOI: 10.2210/pdb7og5/pdb
• EMDB information: 12878
• Descriptor: RNA-free ribonuclease P (1 entity in total)
• Functional Keywords: rnasep, metallonuclease, harp, hydrolase
• Biological source: Halorhodospira halophila (strain DSM 244 / SL1) (Ectothiorhodospira halophila (strain DSM 244 / SL1))
• Total number of polymer chains: 12
• Total formula weight: 288616.06

Authors

Altegoer, F.,Bange, G. (deposition date: 2021-05-06, release date: 2021-07-07, Last modification date: 2024-07-10)

Primary citation

Feyh, R.,Waeber, N.B.,Prinz, S.,Giammarinaro, P.I.,Bange, G.,Hochberg, G.,Hartmann, R.K.,Altegoer, F.
Structure and mechanistic features of the prokaryotic minimal RNase P.
Elife, 10:-, 2021

PubMed Abstract: Endonucleolytic removal of 5'-leader sequences from tRNA precursor transcripts (pre-tRNAs) by ribonuclease P (RNase P) is essential for protein synthesis. Beyond RNA-based RNase P enzymes, protein-only versions of the enzyme exert this function in various eukarya (there termed PRORPs) and in some bacteria ( and close relatives); both enzyme types belong to distinct subgroups of the PIN domain metallonuclease superfamily. Homologs of RNase P (HARPs) are also expressed in some other bacteria and many archaea, where they coexist with RNA-based RNase P and do not represent the main RNase P activity. Here, we solved the structure of the bacterial HARP from by cryo-electron microscopy, revealing a novel screw-like dodecameric assembly. Biochemical experiments demonstrate that oligomerization is required for RNase P activity of HARPs. We propose that the tRNA substrate binds to an extended spike-helix (SH) domain that protrudes from the screw-like assembly to position the 5'-end in close proximity to the active site of the neighboring dimer. The structure suggests that eukaryotic PRORPs and prokaryotic HARPs recognize the same structural elements of pre-tRNAs (tRNA elbow region and cleavage site). Our analysis thus delivers the structural and mechanistic basis for pre-tRNA processing by the prokaryotic HARP system.

PubMed: 34180399
DOI: 10.7554/eLife.70160

Experimental method

ELECTRON MICROSCOPY (3.37 Å)