6OF4

Precursor ribosomal RNA processing complex, apo-state.

Summary for 6OF4

• Entry DOI: 10.2210/pdb6of4/pdb
• EMDB information: 20042
• Descriptor: Ribonuclease, CLP1_P domain-containing protein (2 entities in total)
• Functional Keywords: complex, ribonuclease, polynucleotide kinase, rna binding protein
• Biological source: Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719); More
• Total number of polymer chains: 4
• Total formula weight: 227006.82

Authors

Pillon, M.C.,Hsu, A.L.,Krahn, J.M.,Williams, J.G.,Goslen, K.H.,Sobhany, M.,Borgnia, M.J.,Stanley, R.E. (deposition date: 2019-03-28, release date: 2019-09-11, Last modification date: 2024-03-20)

Primary citation

Pillon, M.C.,Hsu, A.L.,Krahn, J.M.,Williams, J.G.,Goslen, K.H.,Sobhany, M.,Borgnia, M.J.,Stanley, R.E.
Cryo-EM reveals active site coordination within a multienzyme pre-rRNA processing complex.
Nat.Struct.Mol.Biol., 26:830-839, 2019

PubMed Abstract: Ribosome assembly is a complex process reliant on the coordination of trans-acting enzymes to produce functional ribosomal subunits and secure the translational capacity of cells. The endoribonuclease (RNase) Las1 and the polynucleotide kinase (PNK) Grc3 assemble into a multienzyme complex, herein designated RNase PNK, to orchestrate processing of precursor ribosomal RNA (rRNA). RNase PNK belongs to the functionally diverse HEPN nuclease superfamily, whose members rely on distinct cues for nuclease activation. To establish how RNase PNK coordinates its dual enzymatic activities, we solved a series of cryo-EM structures of Chaetomium thermophilum RNase PNK in multiple conformational states. The structures reveal that RNase PNK adopts a butterfly-like architecture, harboring a composite HEPN nuclease active site flanked by discrete RNA kinase sites. We identify two molecular switches that coordinate nuclease and kinase function. Together, our structures and corresponding functional studies establish a new mechanism of HEPN nuclease activation essential for ribosome production.

PubMed: 31488907
DOI: 10.1038/s41594-019-0289-8

Experimental method

ELECTRON MICROSCOPY (3.2 Å)