The CCR4-NOT complex physically and functionally interacts with TRAMP and the nuclear exosome

Article Article scientifique Article The CCR4-NOT complex physically and functionally interacts with TRAMP and the nuclear exosome eng 2009 author Azzouz Nowel 644417 author Panasenko Olesya 629191 author Colau Geoffroy 683059 author Collart Martine 0000-0001-6955-1773 27009 e6760 10.1371/journal.pone.0006760 19707589 1932-6203 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2727002/pdf/pone.0006760.pdf BACKGROUND: Ccr4-Not is a highly conserved multi-protein complex consisting in yeast of 9 subunits, including Not5 and the major yeast deadenylase Ccr4. It has been connected functionally in the nucleus to transcription by RNA polymerase II and in the cytoplasm to mRNA degradation. However, there has been no evidence so far that this complex is important for RNA degradation in the nucleus. METHODOLOGY/PRINCIPAL FINDINGS: In this work we point to a new role for the Ccr4-Not complex in nuclear RNA metabolism. We determine the importance of the Ccr4-Not complex for the levels of non-coding nuclear RNAs, such as mis-processed and polyadenylated snoRNAs, whose turnover depends upon the nuclear exosome and TRAMP. Consistently, mutation of both the Ccr4-Not complex and the nuclear exosome results in synthetic slow growth phenotypes. We demonstrate physical interactions between the Ccr4-Not complex and the exosome. First, Not5 co-purifies with the exosome. Second, several exosome subunits co-purify with the Ccr4-Not complex. Third, the Ccr4-Not complex is important for the integrity of large exosome-containing complexes. Finally, we reveal a connection between the Ccr4-Not complex and TRAMP through the association of the Mtr4 helicase with the Ccr4-Not complex and the importance of specific subunits of Ccr4-Not for the association of Mtr4 with the nuclear exosome subunit Rrp6. CONCLUSIONS/SIGNIFICANCE: We propose a model in which the Ccr4-Not complex may provide a platform contributing to dynamic interactions between the nuclear exosome and its co-factor TRAMP. Our findings connect for the first time the different players involved in nuclear and cytoplasmic RNA degradation. Blotting, Northern Blotting, Western Chromatography, Affinity Exosomes/*metabolism Mass Spectrometry Nuclear Receptor Subfamily 4, Group A, Member 2/*metabolism Protein Binding Receptors, CCR4/*metabolism Receptors, Tumor Necrosis Factor, Member 25/*metabolism Dewey 616 54 Département de microbiologie et médecine moléculaire 21B false 58 Caractérisation génétique et biochimique du complexe Ccr4-Not conservé 81 PloS one 4 8 3bce7160-0c62-456a-9fa5-701c7931ee3a Article Public file1.pdf 1161405 application/pdf CC BY openAccess Faculté de médecine / Section de médecine fondamentale / Département de microbiologie et médecine moléculaire

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The CCR4-NOT complex physically and functionally interacts with TRAMP and the nuclear exosome	PloS one			2009	724	290

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Colau, Geoffroy