RNPC1, an RNA-binding protein and a target of the p53 family, is required for maintaining the stability of the basal and stress-induced p21 transcript

Cells form a bipolar spindle during mitosis to ensure accurate chromosome segregation. Proper spindle architecture is established by a set of kinesin motors and microtubule-associated proteins. In most eukaryotes, kinesin-5 motors are essential for this process, and genetic or chemical inhibition of their activity leads to the emergence of monopolar spindles and cell death. However, these deficiencies can be rescued by simultaneous inactivation of kinesin-14 motors, as they counteract kinesin-5. We conducted detailed genetic analyses in fission yeast to understand the mechanisms driving spindle assembly in the absence of kinesin-5. Here we show that deletion of the nrp1 gene, which encodes a putative RNA-binding protein with unknown function, can rescue temperature sensitivity caused by cut7-22, a fission yeast kinesin-5 mutant. Interestingly, kinesin-14/Klp2 levels on the spindles in the cut7 mutants were significantly reduced by the nrp1 deletion, although the total levels of Klp2 and the stability of spindle microtubules remained unaffected. Moreover, RNA-binding motifs of Nrp1 are essential for its cytoplasmic localization and function. We have also found that a portion of Nrp1 is spatially and functionally sequestered by chaperone-based protein aggregates upon mild heat stress and limits cell division at high temperatures. We propose that Nrp1 might be involved in post-transcriptional regulation through its RNA-binding ability to promote the loading of Klp2 on the spindle microtubules.

Download Full-text

Polyamines Regulate the Stability of Activating Transcription Factor-2 mRNA through RNA-binding Protein HuR in Intestinal Epithelial Cells

Molecular Biology of the Cell ◽

10.1091/mbc.e07-07-0675 ◽

2007 ◽

Vol 18 (11) ◽

pp. 4579-4590 ◽

Cited By ~ 55

Author(s):

Lan Xiao ◽

Jaladanki N. Rao ◽

Tongtong Zou ◽

Lan Liu ◽

Bernard S. Marasa ◽

...

Keyword(s):

Transcription Factor ◽

Rna Binding ◽

Binding Protein ◽

Critical Role ◽

Rna Binding Protein ◽

Gene Promoter ◽

Protein Levels ◽

Ribonucleoprotein Complexes ◽

Activating Transcription Factor ◽

The Stability

Maintenance of intestinal mucosal epithelial integrity requires polyamines that modulate the expression of various genes involved in cell proliferation and apoptosis. Recently, polyamines were shown to regulate the subcellular localization of the RNA-binding protein HuR, which stabilizes its target transcripts such as nucleophosmin and p53 mRNAs. The activating transcription factor-2 (ATF-2) mRNA encodes a member of the ATF/CRE-binding protein family of transcription factors and was computationally predicted to be a target of HuR. Here, we show that polyamines negatively regulate ATF-2 expression posttranscriptionally and that polyamine depletion stabilizes ATF-2 mRNA by enhancing the interaction of the 3′-untranslated region (UTR) of ATF-2 with cytoplasmic HuR. Decreasing cellular polyamines by inhibiting ornithine decarboxylase (ODC) with α-difluoromethylornithine increased the levels of ATF-2 mRNA and protein, whereas increasing polyamines by ectopic ODC overexpression repressed ATF-2 expression. Polyamine depletion did not alter transcription via the ATF-2 gene promoter but increased the stability of ATF-2 mRNA. Increased cytoplasmic HuR in polyamine-deficient cells formed ribonucleoprotein complexes with the endogenous ATF-2 mRNA and specifically bound to 3′-UTR of ATF-2 mRNA on multiple nonoverlapping 3′-UTR segments. Adenovirus-mediated HuR overexpression elevated ATF-2 mRNA and protein levels, whereas HuR silencing rendered the ATF-2 mRNA unstable and prevented increases in ATF-2 mRNA and protein. Furthermore, inhibition of ATF-2 expression prevented the increased resistance of polyamine-deficient cells to apoptosis induced by treatment with tumor necrosis factor-α and cycloheximide. These results indicate that polyamines modulate the stability of ATF-2 mRNA by altering cytoplasmic HuR levels and that polyamine-modulated ATF-2 expression plays a critical role in regulating epithelial apoptosis.

Download Full-text

Hypoxia-inducible factor 1 alpha is regulated by RBM38, a RNA-binding protein and a p53 family target, via mRNA translation

Oncotarget ◽

10.18632/oncotarget.2786 ◽

2014 ◽

Vol 6 (1) ◽

pp. 305-316 ◽

Cited By ~ 14

Author(s):

Seong-Jun Cho ◽

I-Fang Teng ◽

Min Zhang ◽

Tiffany Yin ◽

Yong-Sam Jung ◽

...

Keyword(s):

Rna Binding ◽

Binding Protein ◽

Hypoxia Inducible Factor ◽

Rna Binding Protein ◽

Mrna Translation ◽

P53 Family ◽

Hypoxia Inducible Factor 1

Download Full-text

S1764 Polyamines Regulate the Stability and Translation of MEK-1 mRNA Through RNA-Binding Protein HuR Modulating Apoptosis in Intestinal Epithelial Cells

Gastroenterology ◽

10.1016/s0016-5085(09)61207-5 ◽

2009 ◽

Vol 136 (5) ◽

pp. A-265

Author(s):

Pengyuan Wang ◽

Rao N. Jaladanki ◽

Tongtong Zou ◽

Lan Liu ◽

Lan Xiao ◽

...

Keyword(s):

Epithelial Cells ◽

Rna Binding ◽

Intestinal Epithelial Cells ◽

Binding Protein ◽

Rna Binding Protein ◽

Intestinal Epithelial ◽

The Stability

Download Full-text

RNPC1, an RNA-binding protein and a target of the p53 family, regulates p63 expression through mRNA stability

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.0912594107 ◽

2010 ◽

Vol 107 (21) ◽

pp. 9614-9619 ◽

Cited By ~ 55

Author(s):

J. Zhang ◽

S. Jun Cho ◽

X. Chen

Keyword(s):

Mrna Stability ◽

Rna Binding ◽

Binding Protein ◽

Rna Binding Protein ◽

P53 Family

Download Full-text

The Putative RNA-Binding Protein Dri1 Promotes the Loading of Kinesin-14/Klp2 to the Mitotic Spindle and Is Sequestered into Heat-Induced Protein Aggregates in Fission Yeast

International Journal of Molecular Sciences ◽

10.3390/ijms22094795 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4795

Author(s):

Masashi Yukawa ◽

Mitsuki Ohishi ◽

Yusuke Yamada ◽

Takashi Toda

Keyword(s):

Fission Yeast ◽

Rna Binding ◽

Binding Protein ◽

Rna Binding Protein ◽

Protein Aggregates ◽

Associated Proteins ◽

Spindle Microtubules ◽

The Stability ◽

And Function ◽

Post Transcriptional Regulation

Cells form a bipolar spindle during mitosis to ensure accurate chromosome segregation. Proper spindle architecture is established by a set of kinesin motors and microtubule-associated proteins. In most eukaryotes, kinesin-5 motors are essential for this process, and genetic or chemical inhibition of their activity leads to the emergence of monopolar spindles and cell death. However, these deficiencies can be rescued by simultaneous inactivation of kinesin-14 motors, as they counteract kinesin-5. We conducted detailed genetic analyses in fission yeast to understand the mechanisms driving spindle assembly in the absence of kinesin-5. Here, we show that deletion of the dri1 gene, which encodes a putative RNA-binding protein, can rescue temperature sensitivity caused by cut7-22, a fission yeast kinesin-5 mutant. Interestingly, kinesin-14/Klp2 levels on the spindles in the cut7 mutants were significantly reduced by the dri1 deletion, although the total levels of Klp2 and the stability of spindle microtubules remained unaffected. Moreover, RNA-binding motifs of Dri1 are essential for its cytoplasmic localization and function. We have also found that a portion of Dri1 is spatially and functionally sequestered by chaperone-based protein aggregates upon mild heat stress and limits cell division at high temperatures. We propose that Dri1 might be involved in post-transcriptional regulation through its RNA-binding ability to promote the loading of Klp2 on the spindle microtubules.

Download Full-text

RBP38, a Novel RNA-Binding Protein from Trypanosomatid Mitochondria, Modulates RNA Stability

Eukaryotic Cell ◽

10.1128/ec.2.3.560-568.2003 ◽

2003 ◽

Vol 2 (3) ◽

pp. 560-568 ◽

Cited By ~ 27

Author(s):

Sandro Sbicego ◽

Juan D. Alfonzo ◽

Antonio M. Estévez ◽

Mary Anne T. Rubio ◽

Xuedong Kang ◽

...

Keyword(s):

Rna Binding ◽

Dissociation Constants ◽

Binding Protein ◽

Rna Stability ◽

Rna Binding Protein ◽

Homologous Gene ◽

Mitochondrial Rna ◽

Isolation And Characterization ◽

Labeled Rna ◽

The Stability

ABSTRACT We describe here the isolation and characterization of a novel RNA-binding protein, RBP38, from Leishmania tarentolae mitochondria. This protein does not contain any known RNA-binding motifs and is highly conserved among the trypanosomatids, but no homologues were found in other organisms. Recombinant LtRBP38 binds single and double-stranded (ds) RNA substrates with dissociation constants in the 100 nM range, as determined by fluorescence polarization analysis. Downregulation of expression of the homologous gene, TbRBP38, in procyclic Trypanosoma brucei by using conditional dsRNA interference resulted in 80% reduction of steady-state levels of RNAs transcribed from both maxicircle and minicircle DNA. In organello pulse-chase labeling experiments were used to determine the stability of RNAs in mitochondria that were depleted of TbRBP38. The half-life of metabolically labeled RNA decreased from ∼160 to ∼60 min after depletion. In contrast, there was no change in transcriptional activity. These observations suggest a role of RBP38 in stabilizing mitochondrial RNA.

Download Full-text

The RNA-Binding Protein Rasputin/G3BP Enhances the Stability and Translation of Its Target mRNAs

Cell Reports ◽

10.1016/j.celrep.2020.02.066 ◽

2020 ◽

Vol 30 (10) ◽

pp. 3353-3367.e7 ◽

Cited By ~ 4

Author(s):

John D. Laver ◽

Jimmy Ly ◽

Allison K. Winn ◽

Angelo Karaiskakis ◽

Sichun Lin ◽

...

Keyword(s):

Rna Binding ◽

Binding Protein ◽

Rna Binding Protein ◽

Target Mrnas ◽

The Stability

Download Full-text

The RNA-binding protein HuR is a novel target of Pirh2 E3 ubiquitin ligase

Cell Death and Disease ◽

10.1038/s41419-021-03871-w ◽

2021 ◽

Vol 12 (6) ◽

Author(s):

Alexandra Daks ◽

Alexey Petukhov ◽

Olga Fedorova ◽

Oleg Shuvalov ◽

Alena Kizenko ◽

...

Keyword(s):

Heat Shock ◽

Ubiquitin Ligase ◽

Rna Binding ◽

Binding Protein ◽

Rna Binding Protein ◽

E3 Ubiquitin Ligase ◽

Ring Finger ◽

P53 Family ◽

Associated Proteins ◽

Novel Target

AbstractThe RING-finger protein Pirh2 is a p53 family-specific E3 ubiquitin ligase. Pirh2 also ubiquitinates several other important cellular factors and is involved in carcinogenesis. However, its functional role in other cellular processes is poorly understood. To address this question, we performed a proteomic search for novel interacting partners of Pirh2. Using the GST-pulldown approach combined with LC-MS/MS, we revealed 225 proteins that interacted with Pirh2. We found that, according to the GO description, a large group of Pirh2-associated proteins belonged to the RNA metabolism group. Importantly, one of the identified proteins from that group was an RNA-binding protein ELAVL1 (HuR), which is involved in the regulation of splicing and protein stability of several oncogenic proteins. We demonstrated that Pirh2 ubiquitinated the HuR protein facilitating its proteasome-mediated degradation in cells. Importantly, the Pirh2-mediated degradation of HuR occurred in response to heat shock, thereby affecting the survival rate of HeLa cells under elevated temperature. Functionally, Pirh2-mediated degradation of HuR augmented the level of c-Myc expression, whose RNA level is otherwise attenuated by HuR. Taken together, our data indicate that HuR is a new target of Pirh2 and this functional interaction contributes to the heat-shock response of cancer cells affecting their survival.

Download Full-text

MAP kinase Slt2p attenuates cell wall mRNA decay by downregulating the RNA-binding protein Rbp1p in response to stress

10.1101/2020.09.30.319939 ◽

2020 ◽

Author(s):

Lin-Chun Chang ◽

Yu-Chieh Wu ◽

Yu-Yun Chang ◽

Fang-Jen Lee

Keyword(s):

Cell Wall ◽

Map Kinase ◽

Rna Binding ◽

Binding Protein ◽

Rna Binding Protein ◽

Wall Stress ◽

Cell Wall Integrity ◽

Signaling Cascade ◽

Cell Wall Stress ◽

The Stability

AbstractThe yeast cell wall integrity (CWI) MAPK pathway is a signaling cascade function in maintaining cell wall integrity under stressful environmental conditions. Recently, the activity and signaling of Slt2p (Mpk1p) MAP kinase has been shown to control assembly of the processing body (P-body) upon cell wall stresses, implicating its posttranscriptional role in decay of cell wall mRNAs. However, how Slt2p MAP kinase directly regulates the stability of cell wall transcripts during cell wall stress remains unclear. Here, we reported that the RNA-binding protein Rbp1p (Ngr1p) is a downstream effector and target of Slt2p MAP kinase during activation of the cell wall stress signaling cascade. In addition to the well-defined target mitochondrial porin mRNA, we found that Rbp1p also negatively regulates the stability of a subset of Slt2p-regulated cell wall transcripts. Deletion of RBP1 increases the level of cell wall transcripts and partially suppresses the hypersensitivity of the slt2Δ deletion strain to cell wall damage. Slt2p is necessary for cell wall stress-induced stabilization of cell wall transcripts. Deletion of RBP1 compromises the destabilization of cell wall transcripts in slt2Δ mutants under cell wall stress. Notably, C-terminal deleted Slt2p impairs its function in promoting turnover of the Rbp1p protein and fails to stabilize cell wall transcripts, although it can complement the growth defect of the slt2Δ strain upon cell wall stress. Altogether, our results demonstrate that MAP kinase Slt2p attenuates CWI mRNA decay in response to cell wall damage by downregulating the activity of the RNA-binding protein Rbp1p.

Download Full-text