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Lai CC, Chiu WY, Chen YT, Wu CL, Lee FJS. The SNARE-associated protein Sft2 functions in Imh1-mediated SNARE recycling transport upon ER stress. Mol Biol Cell 2023; 34:ar112. [PMID: 37610835 PMCID: PMC10559307 DOI: 10.1091/mbc.e23-01-0019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 08/07/2023] [Accepted: 08/15/2023] [Indexed: 08/25/2023] Open
Abstract
Vesicular trafficking involving SNARE proteins play a crucial role in the delivery of cargo to the target membrane. Arf-like protein 1 (Arl1) is an important regulator of the endosomal trans-Golgi network (TGN) and secretory trafficking. In yeast, ER stress-enhances Arl1 activation and Golgin Imh1 recruitment to the late-Golgi. Although Arl1 and Imh1 are critical for GARP-mediated endosomal SNARE-recycling transport in response to ER stress, their downstream effectors are unknown. Here, we report that the SNARE-associated protein Sft2 acts downstream of the Arl1-Imh1 axis to regulate SNARE recycling upon ER stress. We first demonstrated that Sft2 is required for Tlg1/Snc1 SNARE-recycling transport under tunicamycin-induced ER stress. Interestingly, we found that Imh1 regulates Tlg2 retrograde transport to the late-Golgi under ER stress, which in turn is required for Sft2 targeting to the late-Golgi. We further showed that Sft2 with 40 amino acids deleted from the N-terminus exhibits defective mediation of SNARE recycling and decreased association with Tlg1 under ER stress. Finally, we demonstrated that Sft2 is required for GARP-dependent endosome-to-Golgi transport in the absence of Rab protein Ypt6. This study highlights Sft2 as a critical downstream effector of the Arl1-Imh1 axis, mediating the endosome-to-Golgi transport of SNAREs.
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Affiliation(s)
- Chun-Chi Lai
- Institute of Molecular Medicine, National Taiwan University, Taipei 10002, Taiwan
- Center of Precision Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | - Wan-Yun Chiu
- Institute of Molecular Medicine, National Taiwan University, Taipei 10002, Taiwan
- Center of Precision Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | - Yan-Ting Chen
- Institute of Molecular Medicine, National Taiwan University, Taipei 10002, Taiwan
- Center of Precision Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | - Chia-Lu Wu
- Institute of Molecular Medicine, National Taiwan University, Taipei 10002, Taiwan
- Center of Precision Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | - Fang-Jen S. Lee
- Institute of Molecular Medicine, National Taiwan University, Taipei 10002, Taiwan
- Center of Precision Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
- Department of Medical Research, National Taiwan University Hospital, Taipei 100, Taiwan
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Muse O, Patell R, Peters CG, Yang M, El-Darzi E, Schulman S, Falanga A, Marchetti M, Russo L, Zwicker JI, Flaumenhaft R. The unfolded protein response links ER stress to cancer-associated thrombosis. JCI Insight 2023; 8:e170148. [PMID: 37651191 PMCID: PMC10629814 DOI: 10.1172/jci.insight.170148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 08/29/2023] [Indexed: 09/02/2023] Open
Abstract
Thrombosis is a common complication of advanced cancer, yet the cellular mechanisms linking malignancy to thrombosis are poorly understood. The unfolded protein response (UPR) is an ER stress response associated with advanced cancers. A proteomic evaluation of plasma from patients with gastric and non-small cell lung cancer who were monitored prospectively for venous thromboembolism demonstrated increased levels of UPR-related markers in plasma of patients who developed clots compared with those who did not. Release of procoagulant activity into supernatants of gastric, lung, and pancreatic cancer cells was enhanced by UPR induction and blocked by antagonists of the UPR receptors inositol-requiring enzyme 1α (IRE1α) and protein kinase RNA-like endoplasmic reticulum kinase (PERK). Release of extracellular vesicles bearing tissue factor (EVTFs) from pancreatic cancer cells was inhibited by siRNA-mediated knockdown of IRE1α/XBP1 or PERK pathways. Induction of UPR did not increase tissue factor (TF) synthesis, but rather stimulated localization of TF to the cell surface. UPR-induced TF delivery to EVTFs was inhibited by ADP-ribosylation factor 1 knockdown or GBF1 antagonism, verifying the role of vesicular trafficking. Our findings show that UPR activation resulted in increased vesicular trafficking leading to release of prothrombotic EVTFs, thus providing a mechanistic link between ER stress and cancer-associated thrombosis.
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Affiliation(s)
- Oluwatoyosi Muse
- Division of Hemostasis and Thrombosis, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Rushad Patell
- Division of Hemostasis and Thrombosis, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Christian G. Peters
- Division of Hemostasis and Thrombosis, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Moua Yang
- Division of Hemostasis and Thrombosis, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Emale El-Darzi
- Division of Hemostasis and Thrombosis, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Sol Schulman
- Division of Hemostasis and Thrombosis, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Anna Falanga
- Immunohematology and Transfusion Medicine, ASST Papa Giovanni XXIII, Bergamo, Italy
| | - Marina Marchetti
- Immunohematology and Transfusion Medicine, ASST Papa Giovanni XXIII, Bergamo, Italy
| | - Laura Russo
- Immunohematology and Transfusion Medicine, ASST Papa Giovanni XXIII, Bergamo, Italy
| | - Jeffrey I. Zwicker
- Hematology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Robert Flaumenhaft
- Division of Hemostasis and Thrombosis, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
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Chen N, Yang S, You D, Shen J, Ruan B, Wu M, Zhang J, Luo X, Tang H. Systematic genetic modifications of cell wall biosynthesis enhanced the secretion and surface-display of polysaccharide degrading enzymes in Saccharomyces cerevisiae. Metab Eng 2023; 77:273-282. [PMID: 37100192 DOI: 10.1016/j.ymben.2023.04.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 03/31/2023] [Accepted: 04/15/2023] [Indexed: 04/28/2023]
Abstract
Saccharomyces cerevisiae is a robust cell factory to secrete or surface-display cellulase and amylase for the conversion of agricultural residues into valuable chemicals. Engineering the secretory pathway is a well-known strategy for overproducing these enzymes. Although cell wall biosynthesis can be tightly linked to the secretory pathway by regulation of all involved processes, the effect of its modifications on protein production has not been extensively studied. In this study, we systematically studied the effect of engineering cell wall biosynthesis on the activity of cellulolytic enzyme β-glucosidase (BGL1) by comparing seventy-nine gene knockout S. cerevisiae strains and newly identified that inactivation of DFG5, YPK1, FYV5, CCW12 and KRE1 obviously improved BGL1 secretion and surface-display. Combinatorial modifications of these genes, particularly double deletion of FVY5 and CCW12, along with the use of rich medium, increased the activity of secreted and surface-displayed BGL1 by 6.13-fold and 7.99-fold, respectively. Additionally, we applied this strategy to improve the activity of the cellulolytic cellobiohydrolase and amylolytic α-amylase. Through proteomic analysis coupled with reverse engineering, we found that in addition to the secretory pathway, regulation of translation processes may also involve in improving enzyme activity by engineering cell wall biosynthesis. Our work provides new insight into the construction of a yeast cell factory for efficient production of polysaccharide degrading enzymes.
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Affiliation(s)
- Nanzhu Chen
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Shuo Yang
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China; State Key Laboratory of Biobased Material and Green Papermaking, School of Bioengineering, Key Laboratory of Shandong Microbial Engineering, Qilu University of Technology, 3501 Daxue Road, Jinan, 250353, China
| | - Dawei You
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Junfeng Shen
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Banlai Ruan
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Mei Wu
- Synceres Biosciences (Shenzhen) Co., Ltd, Nanshan Medical Device Industrial Park, Nanhai Avenue, Shenzhen, 518067, China
| | - Jianzhi Zhang
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Xiaozhou Luo
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
| | - Hongting Tang
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
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Involvement of Sec71 and Ubp2 in tunicamycin-induced ER stress response in the fission yeast. Mol Biol Rep 2022; 49:4719-4726. [PMID: 35474054 DOI: 10.1007/s11033-022-07321-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 02/11/2022] [Accepted: 03/02/2022] [Indexed: 10/18/2022]
Abstract
BACKGROUND Accumulation of unfolded or misfolded proteins in the cellular environment result in ER stress and activates the unfolded protein response (UPR). The UPR alleviates ER stress and restores homeostasis, but it triggers cell death under prolonged stress. Here, we aimed to investigate the involvement of Sec71, an Arf-GEF involved in vesicular transport, in the tunicamycin-induced ER stress response. Since deubiquitinases and ER stress are known to be closely linked, we investigated this response by evaluating the potential role of Ubp2, a deubiquitinase, in the ER stress response in fission yeast. METHODS AND RESULTS Tunicamycin-induced ER stress responses were assessed by analyzing cell viability, apoptosis, intracellular oxidation levels, and proteasomal activities in sec71 and ubp2-deficient cells. The cell viability of Δsec71 and Δubp2 decreased after exposure to 0.5 µg/mL tunicamycin. Deleting either ubp2 or sec71 genes significantly decreased proteasomal activity and sensitized cells to ER stress, resulting in increased apoptosis compared with wild-type cells after tunicamycin treatment. DCFDA (2,7-dichlorodihydrofluorescein diacetate) reduction increased in correlation with apoptosis observed in the mutant cells, indicating higher levels of reactive oxygen species. CONCLUSIONS The results highlight the involvement of S. pombe Ubp2 in the known role of the ubiquitin-proteasome system in the ER stress response. We hypothesise that Sec71 is associated with ER homeostasis, and our findings on Sec71 provide new insight into the regulation of cell death mechanisms arising from the ER stress.
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Focus on the Small GTPase Rab1: A Key Player in the Pathogenesis of Parkinson's Disease. Int J Mol Sci 2021; 22:ijms222112087. [PMID: 34769517 PMCID: PMC8584362 DOI: 10.3390/ijms222112087] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/04/2021] [Accepted: 11/06/2021] [Indexed: 12/19/2022] Open
Abstract
Parkinson’s disease (PD) is the second most frequent neurodegenerative disease. It is characterized by the loss of dopaminergic neurons in the substantia nigra and the formation of large aggregates in the survival neurons called Lewy bodies, which mainly contain α-synuclein (α-syn). The cause of cell death is not known but could be due to mitochondrial dysfunction, protein homeostasis failure, and alterations in the secretory/endolysosomal/autophagic pathways. Survival nigral neurons overexpress the small GTPase Rab1. This protein is considered a housekeeping Rab that is necessary to support the secretory pathway, the maintenance of the Golgi complex structure, and the regulation of macroautophagy from yeast to humans. It is also involved in signaling, carcinogenesis, and infection for some pathogens. It has been shown that it is directly linked to the pathogenesis of PD and other neurodegenerative diseases. It has a protective effect against α–σψν toxicity and has recently been shown to be a substrate of LRRK2, which is the most common cause of familial PD and the risk of sporadic disease. In this review, we analyze the key aspects of Rab1 function in dopamine neurons and its implications in PD neurodegeneration/restauration. The results of the current and former research support the notion that this GTPase is a good candidate for therapeutic strategies.
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Halloran M, Ragagnin AMG, Vidal M, Parakh S, Yang S, Heng B, Grima N, Shahheydari H, Soo KY, Blair I, Guillemin GJ, Sundaramoorthy V, Atkin JD. Amyotrophic lateral sclerosis-linked UBQLN2 mutants inhibit endoplasmic reticulum to Golgi transport, leading to Golgi fragmentation and ER stress. Cell Mol Life Sci 2020; 77:3859-3873. [PMID: 31802140 PMCID: PMC11105036 DOI: 10.1007/s00018-019-03394-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 10/28/2019] [Accepted: 11/22/2019] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are fatal neurodegenerative diseases that are related genetically and pathologically. Mutations in the UBQLN2 gene, encoding the ubiquitin-like protein ubiquilin2, are associated with familial ALS/FTD, but the pathophysiological mechanisms remain unclear. Here, we demonstrate that ALS/FTD UBQLN2 mutants P497H and P506T inhibit protein transport from the endoplasmic reticulum (ER) to the Golgi apparatus in neuronal cells. In addition, we observed that Sec31-positive ER exit sites are clustered in UBQLN2T487I patient spinal cord tissues. Both the ER-Golgi intermediate (ERGIC) compartment and the Golgi become disorganised and fragmented. This activates ER stress and inhibits ER-associated degradation. Hence, this study highlights perturbations in secretory protein trafficking and ER homeostasis as pathogenic mechanisms associated with ALS/FTD-associated forms of UBQLN2.
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Affiliation(s)
- Mark Halloran
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Audrey M G Ragagnin
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Marta Vidal
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Sonam Parakh
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Shu Yang
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Benjamin Heng
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Natalie Grima
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Hamideh Shahheydari
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Kai-Ying Soo
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Ian Blair
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Gilles J Guillemin
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Vinod Sundaramoorthy
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Julie D Atkin
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia.
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Melbourne, Australia.
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Palma S, Raffa CI, Garcia-Fabiani MB, Ferretti VA, Zwenger A, Perez Verdera PV, Llontop A, Rojas Bilbao E, Cuartero V, Abba MC, Lacunza E. RHBDD2 overexpression promotes a chemoresistant and invasive phenotype to rectal cancer tumors via modulating UPR and focal adhesion genes. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165810. [PMID: 32339641 DOI: 10.1016/j.bbadis.2020.165810] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 04/07/2020] [Accepted: 04/19/2020] [Indexed: 12/29/2022]
Abstract
The current standard of care for locally advanced rectal cancer (RC) is neoadjuvant radio-chemotherapy (NRC) with 5-fluorouracil (5Fu) as the main drug, followed by surgery and adjuvant chemotherapy. While a group of patients will achieve a pathological complete response, a significant percentage will not respond to the treatment. The Unfolding Protein Response (UPR) pathway is generally activated in tumors and results in resistance to radio-chemotherapy. We previously showed that RHBDD2 gene is overexpressed in the advanced stages of colorectal cancer (CRC) and that it could modulate the UPR pathway. Moreover, RHBDD2 expression is induced by 5Fu. In this study, we demonstrate that the overexpression of RHBDD2 in CACO2 cell line confers resistance to 5Fu, favors cell migration, adhesion and proliferation and has a profound impact on the expression of both, the UPR genes BiP, PERK and CHOP, and on the cell adhesion genes FAK and PXN. We also determined that RHBDD2 binds to BiP protein, the master UPR regulator. Finally, we confirmed that a high expression of RHBDD2 in RC tumors after NRC treatment is associated with the development of local or distant metastases. The collected evidence positions RHBDD2 as a promising prognostic biomarker to predict the response to neoadjuvant therapy in patients with RC.
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Affiliation(s)
- S Palma
- Centro de Investigaciones Inmunológicas Básicas y Aplicadas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
| | - C I Raffa
- Gastroenterology and Proctology Department, Instituto de Oncología Angel H. Roffo, University of Buenos Aires, Buenos Aires, Argentina
| | - M B Garcia-Fabiani
- Instituto de Investigaciones Bioquímicas de La Plata Rodolfo R. Brenner, CONICET, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
| | - V A Ferretti
- Centro de Investigaciones Inmunológicas Básicas y Aplicadas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
| | - A Zwenger
- Grupo Oncológico Cooperativo del Sur (GOCS), Neuquén, Argentina
| | | | - A Llontop
- Pathology Department, Instituto de Oncología Angel H. Roffo, University of Buenos Aires, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - E Rojas Bilbao
- Pathology Department, Instituto de Oncología Angel H. Roffo, University of Buenos Aires, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - V Cuartero
- Clinic Oncology Department, Functional Unit of Digestive Tumors, Instituto de Oncología Angel H. Roffo, University of Buenos Aires, Buenos Aires, Argentina
| | - M C Abba
- Centro de Investigaciones Inmunológicas Básicas y Aplicadas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina
| | - E Lacunza
- Centro de Investigaciones Inmunológicas Básicas y Aplicadas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina.
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Splice switching an oncogenic ratio of SmgGDS isoforms as a strategy to diminish malignancy. Proc Natl Acad Sci U S A 2020; 117:3627-3636. [PMID: 32019878 DOI: 10.1073/pnas.1914153117] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The chaperone protein SmgGDS promotes cell-cycle progression and tumorigenesis in human breast and nonsmall cell lung cancer. Splice variants of SmgGDS, named SmgGDS-607 and SmgGDS-558, facilitate the activation of oncogenic members of the Ras and Rho families of small GTPases through membrane trafficking via regulation of the prenylation pathway. SmgGDS-607 interacts with newly synthesized preprenylated small GTPases, while SmgGDS-558 interacts with prenylated small GTPases. We determined that cancer cells have a high ratio of SmgGDS-607:SmgGDS-558 (607:558 ratio), and this elevated ratio is associated with reduced survival of breast cancer patients. These discoveries suggest that targeting SmgGDS splicing to lower the 607:558 ratio may be an effective strategy to inhibit the malignant phenotype generated by small GTPases. Here we report the development of a splice-switching oligonucleotide, named SSO Ex5, that lowers the 607:558 ratio by altering exon 5 inclusion in SmgGDS pre-mRNA (messenger RNA). Our results indicate that SSO Ex5 suppresses the prenylation of multiple small GTPases in the Ras, Rho, and Rab families and inhibits ERK activity, resulting in endoplasmic reticulum (ER) stress, the unfolded protein response, and ultimately apoptotic cell death in breast and lung cancer cell lines. Furthermore, intraperitoneal (i.p.) delivery of SSO Ex5 in MMTV-PyMT mice redirects SmgGDS splicing in the mammary gland and slows tumorigenesis in this aggressive model of breast cancer. Taken together, our results suggest that the high 607:558 ratio is required for optimal small GTPase prenylation, and validate this innovative approach of targeting SmgGDS splicing to diminish malignancy in breast and lung cancer.
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Manganese-induced cellular disturbance in the baker's yeast, Saccharomyces cerevisiae with putative implications in neuronal dysfunction. Sci Rep 2019; 9:6563. [PMID: 31024033 PMCID: PMC6484083 DOI: 10.1038/s41598-019-42907-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 04/09/2019] [Indexed: 12/24/2022] Open
Abstract
Manganese (Mn) is an essential element, but in humans, chronic and/or acute exposure to this metal can lead to neurotoxicity and neurodegenerative disorders including Parkinsonism and Parkinson’s Disease by unclear mechanisms. To better understand the effects that exposure to Mn2+ exert on eukaryotic cell biology, we exposed a non-essential deletion library of the yeast Saccharomyces cerevisiae to a sub-inhibitory concentration of Mn2+ followed by targeted functional analyses of the positive hits. This screen produced a set of 43 sensitive deletion mutants that were enriched for genes associated with protein biosynthesis. Our follow-up investigations demonstrated that Mn reduced total rRNA levels in a dose-dependent manner and decreased expression of a β-galactosidase reporter gene. This was subsequently supported by analysis of ribosome profiles that suggested Mn-induced toxicity was associated with a reduction in formation of active ribosomes on the mRNAs. Altogether, these findings contribute to the current understanding of the mechanism of Mn-triggered cytotoxicity. Lastly, using the Comparative Toxicogenomic Database, we revealed that Mn shared certain similarities in toxicological mechanisms with neurodegenerative disorders including amyotrophic lateral sclerosis, Alzheimer’s, Parkinson’s and Huntington’s diseases.
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Mateus D, Marini ES, Progida C, Bakke O. Rab7a modulates ER stress and ER morphology. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1865:781-793. [DOI: 10.1016/j.bbamcr.2018.02.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 02/15/2018] [Accepted: 02/28/2018] [Indexed: 02/08/2023]
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11
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Yu Q, Jia C, Dong Y, Zhang B, Xiao C, Chen Y, Wang Y, Li X, Wang L, Zhang B, Li M. Candida albicans autophagy, no longer a bystander: Its role in tolerance to ER stress-related antifungal drugs. Fungal Genet Biol 2015; 81:238-49. [DOI: 10.1016/j.fgb.2015.02.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Revised: 02/12/2015] [Accepted: 02/15/2015] [Indexed: 10/24/2022]
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