The eIF4E-binding protein Eap1 has similar but independent roles in cell growth and gene expression with the cytoplasmic deadenylase Ccr4

Abstract eIF4E-binding proteins (4E-BPs) are translational repressors that compete with eIF4G for binding to eIF4E. Here we investigated the roles of yeast 4E-BPs, Eap1 and Caf20, in cell wall integrity pathway and gene expression. We found that eap1∆ mutation, but not caf20∆ mutation, showed synthetic growth defect with mutation in ROM2 gene encoding Rho1 GEF. The eap1∆ mutation also showed synthetic lethality with mutation in CCR4 gene encoding cytoplasmic deadenylase. Ccr4 functions in degradation of LRG1 mRNA encoding Rho1 GAP. Eap1-Y109A L114A, which could not bind to eIF4E, did not suppress the synthetic lethality of eap1∆ ccr4∆ mutant, suggesting that 4E-binding of Eap1 is important for its function. We also found that eap1∆ mutant showed derepression of stress response gene HSP12. 4E-binding of Eap1 was also required for repression of HSP12 expression. Our results indicate that Eap1 has similar but independent roles in cell growth and gene expression with Ccr4.

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Pbp1 Is Involved in Ccr4- and Khd1-Mediated Regulation of Cell Growth through Association with Ribosomal Proteins Rpl12a and Rpl12b

Eukaryotic Cell ◽

10.1128/ec.00370-12 ◽

2013 ◽

Vol 12 (6) ◽

pp. 864-874 ◽

Cited By ~ 12

Author(s):

Yuichi Kimura ◽

Kaoru Irie ◽

Kenji Irie

Keyword(s):

Cell Growth ◽

Ribosomal Proteins ◽

Rna Binding ◽

Binding Protein ◽

Growth Defect ◽

Gene Encoding ◽

Obvious Effect ◽

Content Type ◽

Double Deletion ◽

Cell Wall Integrity Pathway

ABSTRACT The Saccharomyces cerevisiae Pbp1 [poly(A)-binding protein (Pab1)-binding protein] is believed to be involved in RNA metabolism and regulation of translation, since Pbp1 regulates a length of poly(A) tail and is involved in stress granule (SG) formation. However, a physiological function of Pbp1 remains unclear, since the pbp1 Δ mutation has no obvious effect on cell growth. In this study, we showed that PBP1 genetically interacts with CCR4 and KHD1 , which encode a cytoplasmic deadenylase and an RNA-binding protein, respectively. Ccr4 and Khd1 modulate a signal from Rho1 in the cell wall integrity pathway by regulating the expression of RhoGEF and RhoGAP, and the double deletion of CCR4 and KHD1 confers a severe growth defect displaying cell lysis. We found that the pbp1 Δ mutation suppressed the growth defect caused by the ccr4Δ khd1 Δ mutation. The pbp1 Δ mutation also suppressed the growth defect caused by double deletion of POP2 , encoding another cytoplasmic deadenylase, and KHD1 . Deletion of the gene encoding previously known Pbp1-interacting factor Lsm12, Pbp4, or Mkt1 did not suppress the growth defect of the ccr4Δ khd1 Δ mutant, suggesting that Pbp1 acts independently of these factors in this process. We then screened novel Pbp1-interacting factors and found that Pbp1 interacts with ribosomal proteins Rpl12a and Rpl12b. Similarly to the pbp1 Δ mutation, the rpl12a Δ and rpl12b Δ mutations also suppressed the growth defect caused by the ccr4Δ khd1 Δ mutation. Our results suggest that Pbp1 is involved in the Ccr4- and Khd1-mediated regulation of cell growth through the association with Rpl12a and Rpl12b.

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Deuterium Oxide (D2O) Induces Early Stress Response Gene Expression and Impairs Growth and Metastasis of Experimental Malignant Melanoma

Cancers ◽

10.3390/cancers13040605 ◽

2021 ◽

Vol 13 (4) ◽

pp. 605

Author(s):

Jana Jandova ◽

Anh B. Hua ◽

Jocelyn Fimbres ◽

Georg T. Wondrak

Keyword(s):

Gene Expression ◽

Stress Response ◽

Malignant Melanoma ◽

Tumor Growth ◽

Deuterium Oxide ◽

Human Melanoma ◽

Pharmacological Intervention ◽

Melanoma Metastasis ◽

Response Gene ◽

Stress Response Gene

There are two stable isotopes of hydrogen, protium (1H) and deuterium (2H; D). Cellular stress response dysregulation in cancer represents both a major pathological driving force and a promising therapeutic target, but the molecular consequences and potential therapeutic impact of deuterium (2H)-stress on cancer cells remain largely unexplored. We have examined the anti-proliferative and apoptogenic effects of deuterium oxide (D2O; ‘heavy water’) together with stress response gene expression profiling in panels of malignant melanoma (A375V600E, A375NRAS, G361, LOX-IMVI), and pancreatic ductal adenocarcinoma (PANC-1, Capan-2, or MIA PaCa-2) cells with inclusion of human diploid Hs27 skin fibroblasts. Moreover, we have examined the efficacy of D2O-based pharmacological intervention in murine models of human melanoma tumor growth and metastasis. D2O-induction of apoptosis was substantiated by AV-PI flow cytometry, immunodetection of PARP-1, and pro-caspase 3 cleavage, and rescue by pan-caspase inhibition. Differential array analysis revealed early modulation of stress response gene expression in both A375 melanoma and PANC-1 adenocarcinoma cells elicited by D2O (90%; ≤6 h) (upregulated: CDKN1A, DDIT3, EGR1, GADD45A, HMOX1, NFKBIA, or SOD2 (up to 9-fold; p < 0.01)) confirmed by independent RT-qPCR analysis. Immunoblot analysis revealed rapid onset of D2O-induced stress response phospho-protein activation (p-ERK, p-JNK, p-eIF2α, or p-H2AX) or attenuation (p-AKT). Feasibility of D2O-based chemotherapeutic intervention (drinking water (30% w/w)) was demonstrated in a severe combined immunodeficiency (SCID) mouse melanoma metastasis model using luciferase-expressing A375-Luc2 cells. Lung tumor burden (visualized by bioluminescence imaging) was attenuated by D2O, and inhibition of invasiveness was also confirmed in an in vitro Matrigel transwell invasion assay. D2O supplementation also suppressed tumor growth in a murine xenograft model of human melanoma, and median survival was significantly increased without causing adverse effects. These data demonstrate for the first time that systemic D2O administration impairs growth and metastasis of malignant melanoma through the pharmacological induction of deuterium (2H)-stress.

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Solar simulated ultraviolet radiation inactivates HCoV-NL63 and SARS-CoV-2 coronaviruses at environmentally relevant doses

10.1101/2021.06.25.449831 ◽

2021 ◽

Author(s):

Georg T. Wondrak ◽

Jana Jandova ◽

Spencer J. Williams ◽

Dominik Schenten

Keyword(s):

Gene Expression ◽

Stress Response ◽

Uv Light ◽

Gene Expression Array ◽

Array Analysis ◽

Expression Array ◽

Response Gene ◽

Full Spectrum ◽

Solar Uv ◽

Stress Response Gene

The germicidal properties of short wavelength ultraviolet C (UVC) light are well established and used to inactivate many viruses and other microbes. However, much less is known about germicidal effects of terrestrial solar UV light, confined exclusively to wavelengths in the UVA and UVB regions. Here, we have explored the sensitivity of the human coronaviruses HCoV-NL63 and SARS-CoV-2 to solar-simulated full spectrum ultraviolet light (sUV) delivered at environmentally relevant doses. First, HCoV-NL63 coronavirus inactivation by sUV-exposure was confirmed employing (i) viral plaque assays, (ii) RT-qPCR detection of viral genome replication, and (iii) infection-induced stress response gene expression array analysis. Next, a detailed dose-response relationship of SARS-CoV-2 coronavirus inactivation by sUV was elucidated, suggesting a half maximal suppression of viral infectivity at low sUV doses. Likewise, extended sUV exposure of SARS-CoV-2 blocked cellular infection as revealed by plaque assay and stress response gene expression array analysis. Moreover, comparative (HCoV-NL63 versus SARS-CoV-2) single gene expression analysis by RT-qPCR confirmed that sUV exposure blocks coronavirus-induced redox, inflammatory, and proteotoxic stress responses. Based on our findings, we estimate that solar ground level full spectrum UV light impairs coronavirus infectivity at environmentally relevant doses. Given the urgency and global scale of the unfolding SARS-CoV-2 pandemic, these prototype data suggest feasibility of solar UV-induced viral inactivation, an observation deserving further molecular exploration in more relevant exposure models.

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Ezrin Inhibition Up-regulates Stress Response Gene Expression

Journal of Biological Chemistry ◽

10.1074/jbc.m116.718189 ◽

2016 ◽

Vol 291 (25) ◽

pp. 13257-13270 ◽

Cited By ~ 18

Author(s):

Haydar Çelik ◽

Gülay Bulut ◽

Jenny Han ◽

Garrett T. Graham ◽

Tsion Z. Minas ◽

...

Keyword(s):

Gene Expression ◽

Stress Response ◽

Response Gene ◽

Stress Response Gene

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Inflammation, signaling, DNA repair and stress response gene expression during placental development

Journal of Reproductive Immunology ◽

10.1016/j.jri.2006.08.043 ◽

2006 ◽

Vol 71 (2) ◽

pp. 159 ◽

Cited By ~ 1

Author(s):

M. Meller ◽

D. Abetew ◽

C. Qiu ◽

S. Vadachkoria ◽

D. Luthy ◽

...

Keyword(s):

Gene Expression ◽

Dna Repair ◽

Stress Response ◽

Placental Development ◽

Response Gene ◽

Stress Response Gene

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Endogenous rRNA Sequence Variation Can Regulate Stress Response Gene Expression and Phenotype

Cell Reports ◽

10.1016/j.celrep.2018.08.093 ◽

2018 ◽

Vol 25 (1) ◽

pp. 236-248.e6 ◽

Cited By ~ 29

Author(s):

Chad M. Kurylo ◽

Matthew M. Parks ◽

Manuel F. Juette ◽

Boris Zinshteyn ◽

Roger B. Altman ◽

...

Keyword(s):

Gene Expression ◽

Stress Response ◽

Sequence Variation ◽

Rrna Sequence ◽

Response Gene ◽

Stress Response Gene

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Abstract 211: ATF6 and the Adaptive ER Stress Response Enhances Proliferation and Viability in Mouse Cardiac Stem Cells

Circulation Research ◽

10.1161/res.119.suppl_1.211 ◽

2016 ◽

Vol 119 (suppl_1) ◽

Author(s):

Winston T Stauffer ◽

Shirin Doroudgar ◽

Haley N Stephens ◽

Brandi Bailey ◽

Christopher C Glembotski

Keyword(s):

Gene Expression ◽

Stem Cells ◽

Stress Response ◽

Er Stress ◽

Ischemic Heart ◽

Cardiac Stem Cells ◽

Response Gene ◽

Er Stress Response ◽

Chemical Inhibition ◽

Stress Response Gene

Rationale: Cardiac stem cells (CSCs) are beneficial when administered to infarcted mouse or rat hearts. Though the mechanism of these benefits is unknown, CSC vitality likely plays a major role. Thus, investigating the factors governing CSC survival in the ischemic heart may lead to more effective therapeutic strategies. Our previous studies showed that misfolded proteins accumulate in the sarco/endoplasmic reticulum (SR/ER) of the ischemic heart. The transcription factor, ATF6, is a key component of the adaptive ER stress response because it induces genes that reduce the accumulation of misfolded proteins, improving myocyte survival during ischemic stress. While our lab has shown that, in cardiac myocytes, ATF6 is cardioprotective in the ischemic heart, neither the ER stress response nor ATF6 have been examined in CSCs. We hypothesize that ATF6 and the adaptive ER stress response are critical for optimal survival of CSCs. Objective/Methods: To gauge the relevance of the ER stress response in CSCs, we used MTT assays to compare the viabilities of mouse CSCs to neonatal rat ventricular myocytes (NRVM) subjected to treatments that mimic ischemic ER stress in the heart. We also assessed the effect of inhibiting ATF6 on both the ER stress response and CSC viability by using chemical inhibition of ATF6 activation or siRNA-mediated ATF6 knock down. Results: We found that, compared to NRVM, CSCs exhibited lower levels of adaptive ER stress response gene expression and decreased viability in response to ER stress. Thus, relative to NRVM, the adaptive ER stress response is not fully developed in CSCs. We also found that either chemical inhibition of ATF6 activation or ATF6 knock down decreased adaptive ER stress response gene expression. Strikingly, ATF6 inhibition or knockdown decreased CSC viability and cell number by as much as 70%. Conclusions: Thus, compared to cardiac myocytes, CSCs exhibit a reduced adaptive ER stress response and are more sensitive to ER stress, suggesting that enhancement of the ATF6-mediated adaptive ER stress response in CSCs may be a viable therapeutic approach for enhancing stem cell-mediated myocardial repair.

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