10.6084/m9.figshare.2068551 Annika U. Heininger Annika U. Heininger Philipp Hackert Philipp Hackert Alexandra Z. Andreou Alexandra Z. Andreou Kum-Loong Boon Kum-Loong Boon Indira Memet Indira Memet Mira Prior Mira Prior Anne Clancy Anne Clancy Bernhard Schmidt Bernhard Schmidt Henning Urlaub Henning Urlaub Enrico Schleiff Enrico Schleiff Katherine E. Sloan Katherine E. Sloan Markus Deckers Markus Deckers Reinhard Lührmann Reinhard Lührmann Jörg Enderlein Jörg Enderlein Dagmar Klostermeier Dagmar Klostermeier Peter Rehling Peter Rehling Markus T. Bohnsack Markus T. Bohnsack Protein cofactor competition regulates the action of a multifunctional RNA helicase in different pathways Taylor & Francis Group 2016 G-patch protein ribosome RNA helicase splicing protein cofactor 2016-01-29 08:53:53 Journal contribution https://tandf.figshare.com/articles/journal_contribution/Protein_cofactor_competition_regulates_the_action_of_a_multifunctional_RNA_helicase_in_different_pathways/2068551 <p>A rapidly increasing number of RNA helicases are implicated in several distinct cellular processes, however, the modes of regulation of multifunctional RNA helicases and their recruitment to different target complexes have remained unknown. Here, we show that the distribution of the multifunctional DEAH-box RNA helicase Prp43 between its diverse cellular functions can be regulated by the interplay of its G-patch protein cofactors. We identify the orphan G-patch protein Cmg1 (YLR271W) as a novel cofactor of Prp43 and show that it stimulates the RNA binding and ATPase activity of the helicase. Interestingly, Cmg1 localizes to the cytoplasm and to the intermembrane space of mitochondria and its overexpression promotes apoptosis. Furthermore, our data reveal that different G-patch protein cofactors compete for interaction with Prp43. Changes in the expression levels of Prp43-interacting G-patch proteins modulate the cellular localization of Prp43 and G-patch protein overexpression causes accumulation of the helicase in the cytoplasm or nucleoplasm. Overexpression of several G-patch proteins also leads to defects in ribosome biogenesis that are consistent with withdrawal of the helicase from this pathway. Together, these findings suggest that the availability of cofactors and the sequestering of the helicase are means to regulate the activity of multifunctional RNA helicases and their distribution between different cellular processes.</p>