Cryo-EM of elongating ribosome with EF-Tu center dot GTP elucidates tRNA proofreading

LOVELAND, A.B., Gabriel DEMO a A.A. KOROSTELEV. Cryo-EM of elongating ribosome with EF-Tu center dot GTP elucidates tRNA proofreading. Nature. LONDON: NATURE PUBLISHING GROUP, 2020, roč. 584, č. 7822, s. "640"-"+", 24 s. ISSN 0028-0836. Dostupné z: https://dx.doi.org/10.1038/s41586-020-2447-x.

Základní údaje

• Originální název: Cryo-EM of elongating ribosome with EF-Tu center dot GTP elucidates tRNA proofreading
• Autoři: LOVELAND, A.B., Gabriel DEMO (703 Slovensko, garant, domácí) a A.A. KOROSTELEV.
• Vydání: Nature, LONDON, NATURE PUBLISHING GROUP, 2020, 0028-0836.

Další údaje

• Originální jazyk: angličtina
• Typ výsledku: Článek v odborném periodiku
• Obor: 10608 Biochemistry and molecular biology
• Stát vydavatele: Německo
• Utajení: není předmětem státního či obchodního tajemství
• WWW: URL
• Impakt faktor: Impact factor: 49.962
• Kód RIV: RIV/00216224:14740/20:00118257
• Organizační jednotka: Středoevropský technologický institut
• Doi: http://dx.doi.org/10.1038/s41586-020-2447-x
• UT WoS: 000544885800003
• Klíčová slova anglicky: AMINOACYL-TRANSFER-RNA; ALLOSTERIC 3-SITE MODEL; CRYSTAL-STRUCTURE; ESCHERICHIA-COLI; STRUCTURAL BASIS; PROTEIN L7/12; 70S RIBOSOME; VISUALIZATION; RESOLUTION; HYDROLYSIS
• Štítky: rivok
• Příznaky: Mezinárodní význam, Recenzováno

Anotace

Ribosomes accurately decode mRNA by proofreading each aminoacyl-tRNA that is delivered by the elongation factor EF-Tu(1). To understand the molecular mechanism of this proofreading step it is necessary to visualize GTP-catalysed elongation, which has remained a challenge(2-4). Here we use time-resolved cryogenic electron microscopy to reveal 33 ribosomal states after the delivery of aminoacyl-tRNA by EF-Tu center dot GTP. Instead of locking cognate tRNA upon initial recognition, the ribosomal decoding centre dynamically monitors codon-anticodon interactions before and after GTP hydrolysis. GTP hydrolysis enables the GTPase domain of EF-Tu to extend away, releasing EF-Tu from tRNA. The 30S subunit then locks cognate tRNA in the decoding centre and rotates, enabling the tRNA to bypass 50S protrusions during accommodation into the peptidyl transferase centre. By contrast, the decoding centre fails to lock near-cognate tRNA, enabling the dissociation of near-cognate tRNA both during initial selection (before GTP hydrolysis) and proofreading (after GTP hydrolysis). These findings reveal structural similarity between ribosomes in initial selection states(5,6)and in proofreading states, which together govern the efficient rejection of incorrect tRNA. Time-resolved cryogenic electron microscopy structures of a ribosome during the delivery of aminoacyl-tRNA by EF-Tu center dot GTP capture 33 ribosomal states, enabling visualization of the initial selection, proofreading and peptidyl transfer stages.