Oncoprotein CoAA repeats interact with RNA polymerase II CTD repeats

AbstractThe heptad repeating sequence of the C-terminal domain (CTD) of the largest subunit of RNA polymerase II is highly conserved in eukaryotes. In yeast, a CTD code consisting of pairs of heptad repeats is essential for viability. However, the strict requirement of diheptad repeats for the CTD function in transcription and splicing is unexplained. Here we show that CoAA (gene symbol RBM14), an oncoprotein and mammalian transcriptional coactivator, possesses diheptad repeats and directly interacts with the CTD. CoAA comprises 27 copies of tyrosine-rich repeats and regulates pre-mRNA synthesis and alternative splicing. Tyrosine substitutions in either the CoAA repeats or the CTD repeats diminish their interactions. Ser2- or Ser5-phosphorylated CTD peptides exhibit higher binding affinity to CoAA than the corresponding non-phosphorylated CTD peptide. CoAA dynamically interacts with both the CTD and hnRNP M, which is an alternative splicing regulator also comprising diheptad repeats. Arginine methylation of CoAA switches its interaction from the hnRNP M repeats to the CTD repeats. This study provides a mechanism for CoAA at the interface of transcription and alternative splicing, and explains the functional requirement of diheptad repeats in the CTD. In the human genome, tyrosine-rich repeats similar to the CoAA repeats were only found in six oncoproteins including EWS and SYT. We suggest that the diheptad sequence is one of the signature features for the CTD interaction among oncoproteins involved in transcription and alternative splicing. We anticipate that direct RNA Pol II interaction is a mechanism in oncogenesis.

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RNA polymerase II CTD interactome with 3′ processing and termination factors in fission yeast and its impact on phosphate homeostasis

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1810711115 ◽

2018 ◽

Vol 115 (45) ◽

pp. E10652-E10661 ◽

Cited By ~ 12

Author(s):

Ana M. Sanchez ◽

Stewart Shuman ◽

Beate Schwer

Keyword(s):

Gene Expression ◽

Rna Polymerase ◽

Fission Yeast ◽

Rna Polymerase Ii ◽

Noncoding Rna ◽

Synthetically Lethal ◽

Heptad Repeats ◽

Carboxy Terminal ◽

Key Steps ◽

Rna Polymerase Ii Ctd

The carboxy-terminal domain (CTD) code encrypted within the Y1S2P3T4S5P6S7heptad repeats of RNA polymerase II (Pol2) is deeply rooted in eukaryal biology. Key steps to deciphering the code are identifying the events in gene expression that are governed by individual “letters” and then defining a vocabulary of multiletter “words” and their meaning. Thr4 and Ser7 exert opposite effects on the fission yeastpho1gene, expression of which is repressed under phosphate-replete conditions by transcription of an upstream flanking long noncoding RNA (lncRNA). Here we attribute the derepression ofpho1by a CTD-S7Amutation to precocious termination of lncRNA synthesis, an effect that is erased by mutations of cleavage-polyadenylation factor (CPF) subunits Ctf1, Ssu72, Ppn1, Swd22, and Dis2 and termination factor Rhn1. By contrast, a CTD-T4Amutation hyperrepressespho1, as do CPF subunit and Rhn1 mutations, implying thatT4Areduces lncRNA termination. Moreover, CTD-T4Ais synthetically lethal withppn1∆ andswd22∆, signifying that Thr4 and the Ppn1•Swd22 module play important, functionally redundant roles in promoting Pol2 termination. We find that Ppn1 and Swd22 become essential for viability when the CTD array is curtailed and thatS7Aovercomes the need for Ppn1•Swd22 in the short CTD context. Mutational synergies highlight redundant essential functions of (i) Ppn1•Swd22 and Rhn1, (ii) Ppn1•Swd22 and Ctf1, and (iii) Ssu72 and Dis2 phosphatases. CTD allelesY1F,S2A, andT4Ahave overlapping synthetic lethalities withppn1∆ andswd22∆, suggesting that Tyr1-Ser2-Thr4 form a three-letter CTD word that abets termination, with Rhn1 being a likely “reader” of this word.

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Genotoxic Stress Modifies the RNA Polymerase II CTD Code to Regulate Alternative Splicing

The FASEB Journal ◽

10.1096/fasebj.22.1_supplement.102.1 ◽

2008 ◽

Vol 22 (S1) ◽

Author(s):

Jean Y. J. Wang ◽

Shun J. Lee

Keyword(s):

Alternative Splicing ◽

Rna Polymerase ◽

Rna Polymerase Ii ◽

Genotoxic Stress ◽

Rna Polymerase Ii Ctd

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Extension of the minimal functional unit of the RNA polymerase II CTD from yeast to mammalian cells

Biology Letters ◽

10.1098/rsbl.2019.0068 ◽

2019 ◽

Vol 15 (5) ◽

pp. 20190068

Author(s):

Nilay Shah ◽

Tim-Michael Decker ◽

Dirk Eick

Keyword(s):

Rna Polymerase ◽

Rna Polymerase Ii ◽

Mammalian Cells ◽

Functional Unit ◽

General Structure ◽

Pol Ii ◽

Carboxy Terminal Domain ◽

Heptad Repeats ◽

Carboxy Terminal ◽

Rna Polymerase Ii Ctd

The carboxy-terminal domain (CTD) of the largest subunit of RNA polymerase II (Pol II) consists of 26 and 52 heptad-repeats in yeast and mammals, respectively. Studies in yeast showed that the strong periodicity of the YSPTSPS heptads is dispensable for cell growth and that di-heptads interspersed by spacers can act as minimal functional units (MFUs) to fulfil all essential CTD functions. Here, we show that the MFU of mammalian cells is significantly larger than in yeast and consists of penta-heptads. We further show that the distance between two MFUs is critical for the functions of mammalian CTD. Our study suggests that the general structure of the CTD remained largely unchanged in yeast and mammals; however, besides the number of heptad-repeats, also the length of the MFU significantly increased in mammals.

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