A new yeast poly(A) polymerase complex involved in RNA quality control

VAŇÁČOVÁ, Štěpánka, Jeannette WOLF, Georges MARTIN, Diana BLANK, Sabine DETTWILER, Arno FRIEDLEIN, Hanno LANGEN, Gerard KEITH a Walter KELLER. A new yeast poly(A) polymerase complex involved in RNA quality control. PLoS Biology. 2005, roč. 3, č. 6, s. e189, 12 s. ISSN 1544-9173.

Základní údaje

• Originální název: A new yeast poly(A) polymerase complex involved in RNA quality control
• Název česky: A new yeast poly(A) polymerase complex involved in RNA quality control
• Autoři: VAŇÁČOVÁ, Štěpánka (203 Česká republika, garant), Jeannette WOLF (756 Švýcarsko), Georges MARTIN (756 Švýcarsko), Diana BLANK (756 Švýcarsko), Sabine DETTWILER (756 Švýcarsko), Arno FRIEDLEIN (756 Švýcarsko), Hanno LANGEN (276 Německo), Gerard KEITH (250 Francie) a Walter KELLER (276 Německo).
• Vydání: PLoS Biology, 2005, 1544-9173.

Další údaje

• Originální jazyk: angličtina
• Typ výsledku: Článek v odborném periodiku
• Obor: 10600 1.6 Biological sciences
• Stát vydavatele: Spojené státy
• Utajení: není předmětem státního či obchodního tajemství
• Impakt faktor: Impact factor: 14.672
• Kód RIV: RIV/00216224:14310/05:00036233
• Organizační jednotka: Přírodovědecká fakulta
• UT WoS: 000229992900009
• Klíčová slova česky: polyadenylation; Trf4; Trf5; TRAMP; exosome; RNA degradation; RNA surveillance
• Klíčová slova anglicky: polyadenylation; Trf4; Trf5; TRAMP; exosome; RNA degradation; RNA surveillance
• Štítky: exosome, polyadenylation, RNA degradation, RNA surveillance, TRAMP, Trf4, Trf5
• Příznaky: Mezinárodní význam, Recenzováno

Anotace

Eukaryotic cells contain several unconventional poly(A) polymerases in addition to the canonical enzymes responsible for the synthesis of poly(A) tails of nuclear messenger RNA precursors. The yeast protein Trf4p has been implicated in a quality control pathway that leads to the polyadenylation and subsequent exosome-mediated degradation of hypomethylated initiator tRNAMet (tRNAiMet). Here we show that Trf4p is the catalytic subunit of a new poly(A) polymerase complex that contains Air1p or Air2p as potential RNA-binding subunits, as well as the putative RNA helicase Mtr4p. Comparison of native tRNAiMet with its in vitro transcribed unmodified counterpart revealed that the unmodified RNA was preferentially polyadenylated by affinity-purified Trf4 complex from yeast, as well as by complexes reconstituted from recombinant components. These results and additional experiments with other tRNA substrates suggested that the Trf4 complex can discriminate between native tRNAs and molecules that are incorrectly folded. Moreover, the polyadenylation activity of the Trf4 complex stimulated the degradation of unmodified tRNAiMet by nuclear exosome fractions in vitro. Degradation was most efficient when coupled to the polyadenylation activity of the Trf4 complex, indicating that the poly(A) tails serve as signals for the recruitment of the exosome. This polyadenylation-mediated RNA surveillance resembles the role of polyadenylation in bacterial RNA turnover.

Anotace česky

Eukaryotic cells contain several unconventional poly(A) polymerases in addition to the canonical enzymes responsible for the synthesis of poly(A) tails of nuclear messenger RNA precursors. The yeast protein Trf4p has been implicated in a quality control pathway that leads to the polyadenylation and subsequent exosome-mediated degradation of hypomethylated initiator tRNAMet (tRNAiMet). Here we show that Trf4p is the catalytic subunit of a new poly(A) polymerase complex that contains Air1p or Air2p as potential RNA-binding subunits, as well as the putative RNA helicase Mtr4p. Comparison of native tRNAiMet with its in vitro transcribed unmodified counterpart revealed that the unmodified RNA was preferentially polyadenylated by affinity-purified Trf4 complex from yeast, as well as by complexes reconstituted from recombinant components. These results and additional experiments with other tRNA substrates suggested that the Trf4 complex can discriminate between native tRNAs and molecules that are incorrectly folded. Moreover, the polyadenylation activity of the Trf4 complex stimulated the degradation of unmodified tRNAiMet by nuclear exosome fractions in vitro. Degradation was most efficient when coupled to the polyadenylation activity of the Trf4 complex, indicating that the poly(A) tails serve as signals for the recruitment of the exosome. This polyadenylation-mediated RNA surveillance resembles the role of polyadenylation in bacterial RNA turnover.