Aller au contenu. | Aller à la navigation

Outils personnels

Navigation
Vous êtes ici : Accueil / Équipes / Régulation Post-transcriptionnelle dans l'Infection et l'Oncogenèse - Jalinot/Mocquet / Publications / Functional link between DEAH/RHA helicase Prp43 activation and ATP base binding.

Functional link between DEAH/RHA helicase Prp43 activation and ATP base binding.

Julien Robert-Paganin, Maral Halladjian, Magali Blaud, Simon Lebaron, Lila Delbos, Florian Chardon, Regine Capeyrou, Odile Humbert, Yves Henry, Anthony K Henras, Stephane Rety, and Nicolas Leulliot (2017)

Nucleic Acids Res, 45(3):1539-1552.

The DEAH box helicase Prp43 is a bifunctional enzyme from the DEAH/RHA helicase family required both for the maturation of ribosomes and for lariat intron release during splicing. It interacts with G-patch domain containing proteins which activate the enzymatic activity of Prp43 in vitro by an unknown mechanism.In this work, we show that the activation by G-patch domains is linked to the unique nucleotide binding mode of this helicase family. The base of the ATP molecule is stacked between two residues, R159 of the RecA1 domain (R-motif) andF357 of the RecA2 domain (F-motif). Using Prp43 F357A mutants or pyrimidine nucleotides, we show that the lack of stacking of the nucleotide base to the F-motif decouples the NTPase and helicase activities of Prp43. In contrast the R159A mutant (R-motif) showed reduced ATPase and helicase activities. We show that the Prp43 R-motif mutant induces the same phenotype as the absence of the G-patch protein Gno1, strongly suggesting that the processing defects observed in the absence of Gno1 result from a failure to activate the Prp43 helicase. Overall we propose that the stacking between the R- and F-motifs and the nucleotide baseis important for the activity and regulation of this helicase family.

 
automatic medline import

Actions sur le document