Dataset Information

Mechanisms Regulating the Function of Spliceosome-Associated Factor Nrl1 of the Fission Yeast Schizosaccharomyces pombe

ABSTRACT: Pre-mRNA splicing is a key process in the regulation of gene expression as reflected by its disruption in various diseases. Previously, we have demonstrated that the spliceosome-associated factor Nrl1 of the fission yeast S. pombe, except of its role in suppression of accumulation of genome-threatening R-loops, also affects splicing and expression of several genes and non-coding RNAs. To uncover the molecular mechanisms regulating the function of Nrl1, we performed here the systematic analysis of its protein-protein interactions at the domain level. We found that N-terminal region of Nrl1 secures the interaction of Nrl1 with ATP-dependent RNA helicase Mtl1 but is incapable of docking of Nrl1 into the spliceosome. Contrary, the C-terminal region of Nrl1 was found to be critical for the interactions of Nrl1 with other splicing factors and the stable binding of Nrl1 into the spliceosome. Importantly, we showed that splicing function of Nrl1 depends on its phosphorylation. Additionally, we identified two amino acid residues of Nrl1, namely S122 and S131, which are directly phosphorylated by Cka1 protein kinase. Together, our results indicate the novel features involved in the regulation of spliceosome-associated factor Nrl1, defined by its domain-dependent interactions and by the CKII-dependent phosphorylation.

INSTRUMENT(S): LTQ Orbitrap Elite

ORGANISM(S): Schizosaccharomyces Pombe 927

SUBMITTER: Peter Barath

LAB HEAD: Peter Barath

PROVIDER: PXD026669 | Pride | 2021-07-12

REPOSITORIES: Pride

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Publications

Identification of Nrl1 Domains Responsible for Interactions with RNA-Processing Factors and Regulation of Nrl1 Function by Phosphorylation.

Mikolaskova Barbora B Jurcik Matus M Cipakova Ingrid I Selicky Tomas T Jurcik Jan J Polakova Silvia Bagelova SB Stupenova Erika E Dudas Andrej A Sivakova Barbara B Bellova Jana J Barath Peter P Aronica Lucia L Gregan Juraj J Cipak Lubos L

International journal of molecular sciences 20210629 13

Pre-mRNA splicing is a key process in the regulation of gene expression. In the fission yeast <i>Schizosaccharomyces pombe</i>, Nrl1 regulates splicing and expression of several genes and non-coding RNAs, and also suppresses the accumulation of R-loops. Here, we report analysis of interactions between Nrl1 and selected RNA-processing proteins and regulation of Nrl1 function by phosphorylation. Bacterial two-hybrid system (BACTH) assays revealed that the N-terminal region of Nrl1 is important for ...[more]

PMID: 34209806

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	161008_IP_Nrl1_01.raw	Raw
	161008_IP_Nrl1_02.raw	Raw
	200205_S5_01.raw	Raw
	200205_S5_02.raw	Raw
	201120_S30_01.raw	Raw