Thursday, November 15, 2012

GDP and SRL don't mix

Translational GTPases run the ribosomal cycle, and the ribosome talks back - it recruits the GTPases when it is a certain state, affects trGTPase's affinity to G nucleotides and activates the GTP hydrolysis when needed. Using Isothermal Titration Calorimetry we showed that binding of GDP nucleotide and of SRL rRNA element to translational GTPases IF2 and EF-G are mutually exclusive. This suggests a neat mechanism for the destabilisation of the ribosome-bound GDP form of the GTPase: the moor has done his duty, the moor can go.

Due to the technical limitations, the ITC experiments were performed with a 27-nucleotide long RNA piece mimicking the rRNA element as a model. In order to place our results in the framework of the ribosomal cycle we need experiments with the whole ribosome. 


Mitkevich et al., Scientific Reports 2012 2:843, PIMD: 32150791

Wednesday, November 7, 2012

First PhD defence in the lab

Our first PhD defence took place on November 2d, 2012. Viktoriya Shyp has defended her work "G nucleotide regulation of translational GTPases and the stringent response factor RelA". Mike Cashel, the discoverer of ppGpp, served as opponent.

Hurray to Vika!