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Mujizah EY, Kuwana S, Matsumoto K, Gushiken T, Aoyama N, Ishikawa HO, Sasamura T, Umetsu D, Inaki M, Yamakawa T, Baron M, Matsuno K. Numb Suppresses Notch-Dependent Activation of Enhancer of split during Lateral Inhibition in the Drosophila Embryonic Nervous System. Biomolecules 2024; 14:1062. [PMID: 39334829 PMCID: PMC11429637 DOI: 10.3390/biom14091062] [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: 06/17/2024] [Revised: 08/07/2024] [Accepted: 08/14/2024] [Indexed: 09/30/2024] Open
Abstract
The role of Drosophila numb in regulating Notch signaling and neurogenesis has been extensively studied, with a particular focus on its effects on the peripheral nervous system (PNS). Previous studies based on a single loss-of-function allele of numb, numb1, showed an antineurogenic effect on the peripheral nervous system (PNS), which revealed that the wild-type numb suppresses Notch signaling. In the current study, we examined whether this phenotype is consistently observed in loss-of-function mutations of numb. Two more numb alleles, numbEY03840 and numbEY03852, were shown to have an antineurogenic phenotype in the PNS. We also found that introducing a wild-type numb genomic fragment into numb1 homozygotes rescued their antineurogenic phenotype. These results demonstrated that loss-of-function mutations of numb universally induce this phenotype. Many components of Notch signaling are encoded by maternal effect genes, but no maternal effect of numb was observed in this study. The antineurogenic phenotype of numb was found to be dependent on the Enhancer of split (E(spl)), a downstream gene of Notch signaling. We found that the combination of E(spl) homozygous and numb1 homozygous suppressed the neurogenic phenotype of the embryonic central nervous system (CNS) associated with the E(spl) mutation. In the E(spl) allele, genes encoding basic helix-loop-helix proteins, such as m5, m6, m7, and m8, remain. Thus, in the E(spl) allele, derepression of Notch activity by numb mutation can rescue the neurogenic phenotype by increasing the expression of the remaining genes in the E(spl) complex. We also uncovered a role for numb in regulating neuronal projections. Our results further support an important role for numb in the suppression of Notch signaling during embryonic nervous system development.
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Affiliation(s)
- Elzava Yuslimatin Mujizah
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan; (E.Y.M.)
| | - Satoshi Kuwana
- Graduate School of Arts and Sciences, University of Tokyo, Meguro 153-8902, Japan
| | - Kenjiroo Matsumoto
- Institute for Glyco-Core Research, Gifu University, Gifu 501-1193, Japan
| | - Takuma Gushiken
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan; (E.Y.M.)
| | - Naoki Aoyama
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan; (E.Y.M.)
| | | | - Takeshi Sasamura
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan; (E.Y.M.)
| | - Daiki Umetsu
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan; (E.Y.M.)
| | - Mikiko Inaki
- School of Science, Graduate School of Science, University of Hyogo, Ako 678-1297, Japan;
| | - Tomoko Yamakawa
- Department of Industrial Engineering, Chemistry, Bioengineering and Environmental Science Course, National Institute of Technology, Ibaraki College, Hitachinaka 312-8508, Japan
| | - Martin Baron
- School of Biological Sciences, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9PL, UK
| | - Kenji Matsuno
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan; (E.Y.M.)
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Yamakawa T, Yuslimatin Mujizah E, Matsuno K. Notch Signalling Under Maternal-to-Zygotic Transition. Fly (Austin) 2022; 16:347-359. [PMID: 36346359 PMCID: PMC9645253 DOI: 10.1080/19336934.2022.2139981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The development of all animal embryos is initially directed by the gene products supplied by their mothers. With the progression of embryogenesis, the embryo's genome is activated to command subsequent developments. This transition, which has been studied in many model animals, is referred to as the Maternal-to-Zygotic Transition (MZT). In many organisms, including flies, nematodes, and sea urchins, genes involved in Notch signaling are extensively influenced by the MZT. This signaling pathway is highly conserved across metazoans; moreover, it regulates various developmental processes. Notch signaling defects are commonly associated with various human diseases. The maternal contribution of its factors was first discovered in flies. Subsequently, several genes were identified from mutant embryos with a phenotype similar to Notch mutants only upon the removal of the maternal contributions. Studies on these maternal genes have revealed various novel steps in the cascade of Notch signal transduction. Among these genes, pecanex and almondex have been functionally characterized in recent studies. Therefore, in this review, we will focus on the roles of these two maternal genes in Notch signaling and discuss future research directions on its maternal function.
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Affiliation(s)
- Tomoko Yamakawa
- Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka, Japan,CONTACT Tomoko Yamakawa Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka, Japan
| | | | - Kenji Matsuno
- Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka, Japan
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Chen Y, Sun Y, Xu Y, Lin WW, Luo Z, Han Z, Liu S, Qi B, Sun C, Go K, Kang XR, Chen J. Single-Cell Integration Analysis of Heterotopic Ossification and Fibrocartilage Developmental Lineage: Endoplasmic Reticulum Stress Effector Xbp1 Transcriptionally Regulates the Notch Signaling Pathway to Mediate Fibrocartilage Differentiation. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2021:7663366. [PMID: 34737845 PMCID: PMC8563124 DOI: 10.1155/2021/7663366] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 09/21/2021] [Accepted: 10/01/2021] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Regeneration of fibrochondrocytes is essential for the healing of the tendon-bone interface (TBI), which is similar to the formation of neurogenic heterotopic ossification (HO). Through single-cell integrative analysis, this study explored the homogeneity of HO cells and fibrochondrocytes. METHODS This study integrated six datasets, namely, GSE94683, GSE144306, GSE168153, GSE138515, GSE102929, and GSE110993. The differentiation trajectory and key transcription factors (TFs) for HO occurrence were systematically analyzed by integrating single-cell RNA (scRNA) sequencing, bulk RNA sequencing, and assay of transposase accessible chromatin seq. The differential expression and enrichment pathways of TFs in heterotopically ossified tissues were identified. RESULTS HO that mimicked pathological cells was classified into HO1 and HO2 cell subsets. Results of the pseudo-temporal sequence analysis suggested that HO2 is a differentiated precursor cell of HO1. The analysis of integrated scRNA data revealed that ectopically ossified cells have similar transcriptional characteristics to cells in the fibrocartilaginous zone of tendons. The modified SCENIC method was used to identify specific transcriptional regulators associated with ectopic ossification. Xbp1 was defined as a common key transcriptional regulator of ectopically ossified tissues and the fibrocartilaginous zone of tendons. Subsequently, the CellPhoneDB database was completed for the cellular ligand-receptor analysis. With further pathway screening, this study is the first to propose that Xbp1 may upregulate the Notch signaling pathway through Jag1 transcription. Twenty-four microRNAs were screened and were found to be potentially associated with upregulation of XBP1 expression after acute ischemic stroke. CONCLUSION A systematic analysis of the differentiation landscape and cellular homogeneity facilitated a molecular understanding of the phenotypic similarities between cells in the fibrocartilaginous region of tendon and HO cells. Furthermore, by identifying Xbp1 as a hub regulator and by conducting a ligand-receptor analysis, we propose a potential Xbp1/Jag1/Notch signaling pathway.
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Affiliation(s)
- Yisheng Chen
- Department of Orthopedics, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai 200080, China
- Department of Sports Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Yaying Sun
- Department of Sports Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Yuzhen Xu
- Department of Rehabilitation, The Second Affiliated Hospital of Shandong First Medical University, Taian, Shandong Province 271000, China
| | - Wei-Wei Lin
- Department of Neurosurgery, Second Affiliated Hospital of Zhejiang University School of Medicine, Zhejiang University, 88 Jiefang Road, Hangzhou, 310009 Zhejiang, China
| | - Zhiwen Luo
- Department of Sports Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Zhihua Han
- Department of Orthopedics, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai 200080, China
| | - Shaohua Liu
- Department of Sports Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Beijie Qi
- Department of Sports Medicine, Huashan Hospital, Fudan University, Shanghai, China
| | - Chenyu Sun
- Internal Medicine, AMITA Health Saint Joseph Hospital Chicago, 2900 N. Lake Shore Drive, Chicago, 60657 Illinois, USA
| | - Ken Go
- Department of Clinical Training Centre, St. Marianna Hospital, Tokyo, Japan
| | - x.-R. Kang
- Shanghai Jiao Tong University, Shanghai 200080, China
| | - Jiwu Chen
- Department of Orthopedics, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai 200080, China
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Singh R, Smit RB, Wang X, Wang C, Racher H, Hansen D. Reduction of Derlin activity suppresses Notch-dependent tumours in the C. elegans germ line. PLoS Genet 2021; 17:e1009687. [PMID: 34555015 PMCID: PMC8491880 DOI: 10.1371/journal.pgen.1009687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 10/05/2021] [Accepted: 09/08/2021] [Indexed: 11/19/2022] Open
Abstract
Regulating the balance between self-renewal (proliferation) and differentiation is key to the long-term functioning of all stem cell pools. In the Caenorhabditis elegans germline, the primary signal controlling this balance is the conserved Notch signaling pathway. Gain-of-function mutations in the GLP-1/Notch receptor cause increased stem cell self-renewal, resulting in a tumour of proliferating germline stem cells. Notch gain-of-function mutations activate the receptor, even in the presence of little or no ligand, and have been associated with many human diseases, including cancers. We demonstrate that reduction in CUP-2 and DER-2 function, which are Derlin family proteins that function in endoplasmic reticulum-associated degradation (ERAD), suppresses the C. elegans germline over-proliferation phenotype associated with glp-1(gain-of-function) mutations. We further demonstrate that their reduction does not suppress other mutations that cause over-proliferation, suggesting that over-proliferation suppression due to loss of Derlin activity is specific to glp-1/Notch (gain-of-function) mutations. Reduction of CUP-2 Derlin activity reduces the expression of a read-out of GLP-1/Notch signaling, suggesting that the suppression of over-proliferation in Derlin loss-of-function mutants is due to a reduction in the activity of the mutated GLP-1/Notch(GF) receptor. Over-proliferation suppression in cup-2 mutants is only seen when the Unfolded Protein Response (UPR) is functioning properly, suggesting that the suppression, and reduction in GLP-1/Notch signaling levels, observed in Derlin mutants may be the result of activation of the UPR. Chemically inducing ER stress also suppress glp-1(gf) over-proliferation but not other mutations that cause over-proliferation. Therefore, ER stress and activation of the UPR may help correct for increased GLP-1/Notch signaling levels, and associated over-proliferation, in the C. elegans germline. Notch signaling is a highly conserved signaling pathway that is utilized in many cell fate decisions in many organisms. In the C. elegans germline, Notch signaling is the primary signal that regulates the balance between stem cell proliferation and differentiation. Notch gain-of-function mutations cause the receptor to be active, even when a signal that is normally needed to activate the receptor is absent. In the germline of C. elegans, gain-of-function mutations in GLP-1, a Notch receptor, results in over-proliferation of the stem cells and tumour formation. Here we demonstrate that a reduction or loss of Derlin activity, which is a conserved family of proteins involved in endoplasmic reticulum-associated degradation (ERAD), suppresses over-proliferation due to GLP-1/Notch gain-of-function mutations. Furthermore, we demonstrate that a surveillance mechanism utilized in cells to monitor and react to proteins that are not folded properly (Unfolded Protein Response-UPR) must be functioning well in order for the loss of Derlin activity to supress over-proliferation caused by glp-1/Notch gain-of-function mutations. This suggests that activation of the UPR may be the mechanism at work for suppressing this type of over-proliferation, when Derlin activity is reduced. Therefore, decreasing Derlin activity may be a means of reducing the impact of phenotypes and diseases due to certain Notch gain-of-function mutations.
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Affiliation(s)
- Ramya Singh
- Department of Biological Sciences, University of Calgary, Calgary, Canada
| | - Ryan B. Smit
- Department of Biological Sciences, University of Calgary, Calgary, Canada
| | - Xin Wang
- Department of Biological Sciences, University of Calgary, Calgary, Canada
| | - Chris Wang
- Department of Biological Sciences, University of Calgary, Calgary, Canada
| | - Hilary Racher
- Department of Biological Sciences, University of Calgary, Calgary, Canada
| | - Dave Hansen
- Department of Biological Sciences, University of Calgary, Calgary, Canada
- * E-mail:
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Sun P, Fan X, Hu X, Fu X, Wei Q, Zang Y. circPCNX and Pecanex Promote Hepatocellular Carcinoma Cell Viability by Inhibiting miR-506. Cancer Manag Res 2019; 11:10957-10967. [PMID: 32099459 PMCID: PMC6997225 DOI: 10.2147/cmar.s232940] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 12/18/2019] [Indexed: 01/08/2023] Open
Abstract
Introduction Hepatocellular carcinoma (HCC) is one of the most common malignant cancers, while the molecular mechanism is not clear. Circular RNAs (circRNAs) are a class of naturally occurring endogenous noncoding RNAs that prove to play important roles in the occurrence, development and prognosis of HCC. In this study, we focused on an abnormally expressed circular RNA-circPCNX in HCC and study the function of circPCNX and Pecanex (PCNX) in HCC. Methods Circular RNA sequencing was used to find the abnormally expressed circRNAs and qRT-PCR was used to verify it. CCK8 assay, colony formation assay and cell apoptosis assay were used to study biological functions, and Luciferase reporter assay and Western blot analysis were used to study the mechanism. Results We observed that circPCNX and Pecanex were significantly upregulated in tumor tissues of patients with HCC and correlated with clinicopathological variables or prognosis of HCC patients. Functional investigations showed circPCNX and Pecanex could promote the viability of HCC cells. Mechanistic investigations suggested that both circPCNX and Pecanex 3'UTR could bind to miR-506 and subsequently inhibited the miR-506-induced anticarcinogenic effect in HCC. Conclusion Our study revealed the function of circPCNX and Pecanex in promoting HCC progression and acting as biomarkers in the clinical estimate and treatment of HCC.
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Affiliation(s)
- Peng Sun
- Department of Liver Transplantation, The Affiliated Hospital of Qingdao University, Qingdao 266003, People's Republic of China
| | - Xinyi Fan
- Intensive Care Unit, the Affiliated Hospital of Qingdao University, Qingdao 266003, People's Republic of China
| | - Xiao Hu
- Department of Hepatobiliary and Pancreatic Surgery, The Affiliated Hospital of Qingdao University, Qingdao 266003, People's Republic of China
| | - Xiaoyue Fu
- Department of Liver Transplantation, The Affiliated Hospital of Qingdao University, Qingdao 266003, People's Republic of China
| | - Qian Wei
- Department of Hepatobiliary and Pancreatic Surgery, The Affiliated Hospital of Qingdao University, Qingdao 266003, People's Republic of China
| | - Yunjin Zang
- Department of Liver Transplantation, The Affiliated Hospital of Qingdao University, Qingdao 266003, People's Republic of China
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Al Amri WS, Allinson LM, Baxter DE, Bell SM, Hanby AM, Jones SJ, Shaaban AM, Stead LF, Verghese ET, Hughes TA. Genomic and Expression Analyses Define MUC17 and PCNX1 as Predictors of Chemotherapy Response in Breast Cancer. Mol Cancer Ther 2019; 19:945-955. [PMID: 31879365 DOI: 10.1158/1535-7163.mct-19-0940] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 11/12/2019] [Accepted: 12/17/2019] [Indexed: 12/24/2022]
Abstract
Poor-prognosis breast cancers are treated with cytotoxic chemotherapy, but often without any guidance from therapy predictive markers because universally accepted markers are not currently available. Treatment failure, in the form of recurrences, is relatively common. We aimed to identify chemotherapy predictive markers and resistance pathways in breast cancer. Our hypothesis was that tumor cells remaining after neoadjuvant chemotherapy (NAC) contain somatic variants causing therapy resistance, while variants present pre-NAC but lost post-NAC cause sensitivity. Whole-exome sequencing was performed on matched pre- and post-NAC cancer cells, which were isolated by laser microdissection, from 6 cancer cases, and somatic variants selected for or against by NAC were identified. Somatic variant diversity was significantly reduced after therapy (P < 0.05). MUC17 variants were identified in 3 tumors and were selected against by NAC in each case, while PCNX1 variants were identified in 2 tumors and were selected for in both cases, implicating the function of these genes in defining chemoresponse. In vitro knockdown of MUC17 or PCNX1 was associated with significantly increased or decreased chemotherapy sensitivity, respectively (P < 0.05), further supporting their roles in chemotherapy response. Expression was tested for predictive value in two independent cohorts of chemotherapy-treated breast cancers (n = 53, n = 303). Kaplan-Meier analyses revealed that low MUC17 expression was significantly associated with longer survival after chemotherapy, whereas low PCNX1 was significantly associated with reduced survival. We concluded that therapy-driven selection of somatic variants allows identification of chemotherapy response genes. With respect to MUC17 and PCNX1, therapy-driven selection acting on somatic variants, in vitro knockdown data concerning drug sensitivity, and survival analysis of expression levels in patient cohorts all define the genes as mediators of and predictive markers for chemotherapy response in breast cancer.
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Affiliation(s)
- Waleed S Al Amri
- School of Medicine, University of Leeds, Leeds, United Kingdom.,Department of Histopathology and Cytopathology, The Royal Hospital, Muscat, Oman
| | - Lisa M Allinson
- School of Medicine, University of Leeds, Leeds, United Kingdom
| | - Diana E Baxter
- School of Medicine, University of Leeds, Leeds, United Kingdom
| | - Sandra M Bell
- School of Medicine, University of Leeds, Leeds, United Kingdom
| | - Andrew M Hanby
- School of Medicine, University of Leeds, Leeds, United Kingdom.,Department of Histopathology, St. James's University Hospital, Leeds, United Kingdom
| | - Stacey J Jones
- Department of Breast Surgery, Leeds Teaching Hospitals NHS Trust, Leeds, United Kingdom
| | - Abeer M Shaaban
- Histopathology and Cancer Sciences, Queen Elizabeth Hospital Birmingham and University of Birmingham, Birmingham, United Kingdom
| | - Lucy F Stead
- School of Medicine, University of Leeds, Leeds, United Kingdom
| | - Eldo T Verghese
- Department of Histopathology, St. James's University Hospital, Leeds, United Kingdom
| | - Thomas A Hughes
- School of Medicine, University of Leeds, Leeds, United Kingdom.
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7
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Das P, Salazar JL, Li-Kroeger D, Yamamoto S, Nakamura M, Sasamura T, Inaki M, Masuda W, Kitagawa M, Yamakawa T, Matsuno K. Maternal almondex, a neurogenic gene, is required for proper subcellular Notch distribution in early Drosophila embryogenesis. Dev Growth Differ 2019; 62:80-93. [PMID: 31782145 DOI: 10.1111/dgd.12639] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 10/08/2019] [Indexed: 01/03/2023]
Abstract
Notch signaling plays crucial roles in the control of cell fate and physiology through local cell-cell interactions. The core processes of Notch signal transduction are well established, but the mechanisms that fine-tune the pathway in various developmental and post-developmental contexts are less clear. Drosophila almondex, which encodes an evolutionarily conserved double-pass transmembrane protein, was identified in the 1970s as a maternal-effect gene that regulates Notch signaling in certain contexts, but its mechanistic function remains obscure. In this study, we examined the role of almondex in Notch signaling during early Drosophila embryogenesis. We found that in addition to being required for lateral inhibition in the neuroectoderm, almondex is also partially required for Notch signaling-dependent single-minded expression in the mesectoderm. Furthermore, we found that almondex is required for proper subcellular Notch receptor distribution in the neuroectoderm, specifically during mid-stage 5 development. The absence of maternal almondex during this critical window of time caused Notch to accumulate abnormally in cells in a mesh-like pattern. This phenotype did not include any obvious change in subcellular Delta ligand distribution, suggesting that it does not result from a general vesicular-trafficking defect. Considering that dynamic Notch trafficking regulates signal output to fit the specific context, we speculate that almondex may facilitate Notch activation by regulating intracellular Notch receptor distribution during early embryogenesis.
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Affiliation(s)
- Puspa Das
- Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka, Japan
| | - Jose L Salazar
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - David Li-Kroeger
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Shinya Yamamoto
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.,Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, USA
| | - Mitsutoshi Nakamura
- Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka, Japan
| | - Takeshi Sasamura
- Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka, Japan
| | - Mikiko Inaki
- Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka, Japan
| | - Wataru Masuda
- Department of Pathology, Saitama Medical Center, Saitama Medical University, Saitama, Japan
| | - Motoo Kitagawa
- Department of Biochemistry, International University of Health and Welfare, School of Medicine, Chiba, Japan
| | - Tomoko Yamakawa
- Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka, Japan
| | - Kenji Matsuno
- Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka, Japan
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Naveed M, Imran K, Mushtaq A, Mumtaz AS, Janjua HA, Khalid N. In silico functional and tumor suppressor role of hypothetical protein PCNXL2 with regulation of the Notch signaling pathway. RSC Adv 2018; 8:21414-21430. [PMID: 35539910 PMCID: PMC9080940 DOI: 10.1039/c8ra00589c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Accepted: 05/31/2018] [Indexed: 12/21/2022] Open
Abstract
Since the last decade, various genome sequencing projects have led to the accumulation of an enormous set of genomic data; however, numerous protein-coding genes still need to be functionally characterized. These gene products are called "hypothetical proteins". The hypothetical protein pecanex-like protein 2 Homo sapiens (PCNXL2) is found to be mutated in colorectal carcinoma with microsatellite instability; therefore, annotation of the function of PCNXL2 in tumorigenesis is very important. In the present study, bioinformatics analysis of PCNXL2 was performed at the molecular level to assess its role in the progression of cancer for designing new anti-cancer drugs. The retrieved sequence of PCNXL2 was functionally and structurally characterized through the web tools Pfam, Batch CD (conserved domain) search, ExPASy, COACH and I-TASSER directed for pathway analysis and design to explore the intercellular interactions of PCNXL2 involved in cancer development. The present study has shown that PCNXL2 encodes multi-pass transmembrane proteins whose tumor suppressor function may involve regulating Notch signaling by transporting protons across the membrane to provide suitable membrane potential for γ secretase function, which may liberate the Notch intracellular domain NICD from the receptor to inside the cell. Furthermore, domain A of PCNXL2 may exhibit nuclear transport activity of NICD from the cytoplasm to the nucleus through interaction with a nuclear localization signal that may act as an activator for Notch signaling in the nucleus. Conclusively, the tumor suppressor role of PCNXL2 by regulation of the Notch signaling pathway and its functional and structural characteristics are important findings. However, further studies are required to validate the putative role of PCNXL2 as a cancer biomarker in cancer development.
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Affiliation(s)
- Muhammad Naveed
- Department of Biotechnology, Faculty of Life Sciences, University of Central Punjab Lahore 5400 Pakistan +92 301 5524624
- Department of Biotechnology and Biochemistry, University of Gujrat Gujrat 50700 Pakistan
| | - Komal Imran
- Department of Biotechnology and Biochemistry, University of Gujrat Gujrat 50700 Pakistan
| | - Ayesha Mushtaq
- Department of Biotechnology and Biochemistry, University of Gujrat Gujrat 50700 Pakistan
| | - Abdul Samad Mumtaz
- Department of Plant Sciences, Quaid-i-Azam University Islamabad 44500 Pakistan
| | - Hussnain A Janjua
- Department of Industrial Biotechnology, Att-Ur-Rahman School of Applied Biosciences, National University of Sciences and Technology H-12 Islamabad Pakistan
| | - Nauman Khalid
- School of Food and Agricultural Sciences, University of Management and Technology Lahore 54000 Pakistan +92 42 3518478 +92 333 5278329
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Insight into Notch Signaling Steps That Involve pecanex from Dominant-Modifier Screens in Drosophila. Genetics 2018; 209:1099-1119. [PMID: 29853475 DOI: 10.1534/genetics.118.300935] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 05/22/2018] [Indexed: 12/14/2022] Open
Abstract
Notch signaling plays crucial roles in intercellular communications. In Drosophila, the pecanex (pcx) gene, which encodes an evolutionarily conserved multi-pass transmembrane protein, appears to be required to activate Notch signaling in some contexts, especially during neuroblast segregation in the neuroectoderm. Although Pcx has been suggested to contribute to endoplasmic reticulum homeostasis, its functions remain unknown. Here, to elucidate these roles, we performed genetic modifier screens of pcx We found that pcx heterozygotes lacking its maternal contribution exhibit cold-sensitive lethality, which is attributed to a reduction in Notch signaling at decreased temperatures. Using sets of deletions that uncover most of the second and third chromosomes, we identified four enhancers and two suppressors of the pcx cold-sensitive lethality. Among these, five genes encode known Notch-signaling components: big brain, Delta (Dl), neuralized (neur), Brother of Bearded A (BobA), a member of the Bearded (Brd) family, and N-ethylmaleimide-sensitive factor 2 (Nsf2). We showed that BobA suppresses Dl endocytosis during neuroblast segregation in the neuroectoderm, as Brd family genes reportedly do in the mesoderm for mesectoderm specification. Analyses of Nsf2, a key regulator of vesicular fusion, suggested a novel role in neuroblast segregation, which is distinct from Nsf2's previously reported role in imaginal tissues. Finally, jim lovell, which encodes a potential transcription factor, may play a role in Notch signaling during neuroblast segregation. These results reveal new research avenues for Pcx functions and Notch signaling.
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10
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Li J, Tian H, Pan J, Jiang N, Yang J, Zhou C, Xu D, Meng X, Gong Z. Pecanex functions as a competitive endogenous RNA of S-phase kinase associated protein 2 in lung cancer. Cancer Lett 2017; 406:36-46. [DOI: 10.1016/j.canlet.2017.07.030] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 07/20/2017] [Accepted: 07/30/2017] [Indexed: 01/29/2023]
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11
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Liu C, Liang X, Wang J, Zheng Q, Zhao Y, Khan MN, Liu S, Yan Q. Protein O-fucosyltransferase 1 promotes trophoblast cell proliferation through activation of MAPK and PI3K/Akt signaling pathways. Biomed Pharmacother 2017; 88:95-101. [PMID: 28103512 DOI: 10.1016/j.biopha.2017.01.026] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 12/28/2016] [Accepted: 01/03/2017] [Indexed: 12/12/2022] Open
Abstract
Protein O-fucosylation is an important glycosylation modification and plays an important role in embryonic development. Protein O-fucosyltransferase 1 (poFUT1) is an essential enzyme that catalyzes the synthesis of protein O-fucosylation. Our previous studies showed that poFUT1 promoted trophoblast cell migration and invasion at the fetal-maternal interface, but the role of poFUT1 in trophoblast cells proliferation remains unclear. Here, immunohistochemistry data showed that poFUT1 and PCNA levels were decreased in abortion patient's trophoblasts compared with women with normal pregnancies. Our results also showed that poFUT1 promoted trophoblast cell proliferation by CCK-8 assay and cell cycle analysis. PoFUT1 increased the phosphorylation of ERK1/2, p38 MAPK, and PI3K/Akt, while inhibitors of ERK1/2(PD98059), p38 MAPK(SB203580), and PI3K (LY294002) prevented ERK1/2, p38 MAPK, and Akt phosphorylation. Moreover, poFUT1 stimulation of trophoblast cells proliferation correlated with increased cell cycle progression by promoting cells into S-phase. The underlying mechanism involved increased cyclin D1, cyclin E, CDK 2, CDK 4, and pRb expression and decreased levels of the cyclin-dependent kinase inhibitors p21 and p27, which were blocked by inhibitors of the upstream signaling molecules MAPK and PI3K/Akt. In conclusion, poFUT1 promotes trophoblast cell proliferation by activating MAPK and PI3K/Akt signaling pathways.
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Affiliation(s)
- Chang Liu
- Institute of Anaesthesia, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191, People's Republic of China; Department of Biochemistry and Molecular Biology, Dalian Medical University, Liaoning Provincial Core Lab of Glycobiology and Glycoengineering, Dalian 116044, People's Republic of China
| | - Xiaohua Liang
- Dalian Blood Center, Dalian 116001, People's Republic of China
| | - Jiao Wang
- Department of Biochemistry and Molecular Biology, Dalian Medical University, Liaoning Provincial Core Lab of Glycobiology and Glycoengineering, Dalian 116044, People's Republic of China
| | - Qin Zheng
- Department of Biochemistry and Molecular Biology, Dalian Medical University, Liaoning Provincial Core Lab of Glycobiology and Glycoengineering, Dalian 116044, People's Republic of China
| | - Yue Zhao
- Department of Biochemistry and Molecular Biology, Dalian Medical University, Liaoning Provincial Core Lab of Glycobiology and Glycoengineering, Dalian 116044, People's Republic of China
| | - Muhammad Noman Khan
- Department of Biochemistry and Molecular Biology, Dalian Medical University, Liaoning Provincial Core Lab of Glycobiology and Glycoengineering, Dalian 116044, People's Republic of China
| | - Shuai Liu
- Department of Biochemistry and Molecular Biology, Dalian Medical University, Liaoning Provincial Core Lab of Glycobiology and Glycoengineering, Dalian 116044, People's Republic of China.
| | - Qiu Yan
- Department of Biochemistry and Molecular Biology, Dalian Medical University, Liaoning Provincial Core Lab of Glycobiology and Glycoengineering, Dalian 116044, People's Republic of China
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12
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Abstract
Endoplasmic Reticulum (ER) is an organelle where most secretory and membrane proteins are synthesized, folded, and undergo further maturation. As numerous conditions can perturb such ER function, eukaryotic cells are equipped with responsive signaling pathways, widely referred to as the Unfolded Protein Response (UPR). Chronic conditions of ER stress that cannot be fully resolved by UPR, or conditions that impair UPR signaling itself, are associated with many metabolic and degenerative diseases. In recent years, Drosophila has been actively employed to study such connections between UPR and disease. Notably, the UPR pathways are largely conserved between Drosophila and humans, and the mediating genes are essential for development in both organisms, indicating their requirement to resolve inherent stress. By now, many Drosophila mutations are known to impose stress in the ER, and a number of these appear similar to those that underlie human diseases. In addition, studies have employed the strategy of overexpressing human mutations in Drosophila tissues to perform genetic modifier screens. The fact that the basic UPR pathways are conserved, together with the availability of many human disease models in this organism, makes Drosophila a powerful tool for studying human disease mechanisms. [BMB Reports 2015; 48(8): 445-453]
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Affiliation(s)
- Hyung Don Ryoo
- Department of Cell Biology, New York University School of Medicine, New York, NY 10016, USA
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13
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Godin JD, Creppe C, Laguesse S, Nguyen L. Emerging Roles for the Unfolded Protein Response in the Developing Nervous System. Trends Neurosci 2016; 39:394-404. [PMID: 27130659 DOI: 10.1016/j.tins.2016.04.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 03/23/2016] [Accepted: 04/04/2016] [Indexed: 01/04/2023]
Abstract
The unfolded protein response (UPR) is a homeostatic signaling pathway triggered by protein misfolding in the endoplasmic reticulum (ER). Beyond its protective role, it plays important functions during normal development in response to elevated demand for protein folding. Several UPR effectors show dynamic temporal and spatial expression patterns that correlate with milestones of the central nervous system (CNS) development. Here, we discuss recent studies suggesting that a dynamic regulation of UPR supports generation, maturation, and maintenance of differentiated neurons in the CNS. We further highlight studies supporting a developmental vulnerability of CNS to UPR dysregulation, which underlies neurodevelopmental disorders. We believe that a better understanding of UPR functions may provide novel opportunities for therapeutic strategies to fight ER/UPR-associated human neurological disorders.
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Affiliation(s)
- Juliette D Godin
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR7104, University of Strasbourg, Illkirch, France.
| | - Catherine Creppe
- GIGA-Neurosciences, University of Liège, C.H.U. Sart Tilman, Liège 4000, Belgium; Interdisciplinary Cluster for Applied Genoproteomics (GIGA-R), University of Liège, C.H.U. Sart Tilman, Liège 4000, Belgium
| | - Sophie Laguesse
- GIGA-Neurosciences, University of Liège, C.H.U. Sart Tilman, Liège 4000, Belgium; Interdisciplinary Cluster for Applied Genoproteomics (GIGA-R), University of Liège, C.H.U. Sart Tilman, Liège 4000, Belgium
| | - Laurent Nguyen
- GIGA-Neurosciences, University of Liège, C.H.U. Sart Tilman, Liège 4000, Belgium; Interdisciplinary Cluster for Applied Genoproteomics (GIGA-R), University of Liège, C.H.U. Sart Tilman, Liège 4000, Belgium; Walloon Excellence in Lifesciences and Biotechnology (WELBIO), University of Liège, C.H.U. Sart Tilman, Liège 4000, Belgium.
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14
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Ishio A, Sasamura T, Ayukawa T, Kuroda J, Ishikawa HO, Aoyama N, Matsumoto K, Gushiken T, Okajima T, Yamakawa T, Matsuno K. O-fucose monosaccharide of Drosophila Notch has a temperature-sensitive function and cooperates with O-glucose glycan in Notch transport and Notch signaling activation. J Biol Chem 2014; 290:505-19. [PMID: 25378397 DOI: 10.1074/jbc.m114.616847] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Notch (N) is a transmembrane receptor that mediates the cell-cell interactions necessary for many cell fate decisions. N has many epidermal growth factor-like repeats that are O-fucosylated by the protein O-fucosyltransferase 1 (O-Fut1), and the O-fut1 gene is essential for N signaling. However, the role of the monosaccharide O-fucose on N is unclear, because O-Fut1 also appears to have O-fucosyltransferase activity-independent functions, including as an N-specific chaperon. Such an enzymatic activity-independent function could account for the essential role of O-fut1 in N signaling. To evaluate the role of the monosaccharide O-fucose modification in N signaling, here we generated a knock-in mutant of O-fut1 (O-fut1(R245A knock-in)), which expresses a mutant protein that lacks O-fucosyltransferase activity but maintains the N-specific chaperon activity. Using O-fut1(R245A knock-in) and other gene mutations that abolish the O-fucosylation of N, we found that the monosaccharide O-fucose modification of N has a temperature-sensitive function that is essential for N signaling. The O-fucose monosaccharide and O-glucose glycan modification, catalyzed by Rumi, function redundantly in the activation of N signaling. We also showed that the redundant function of these two modifications is responsible for the presence of N at the cell surface. Our findings elucidate how different forms of glycosylation on a protein can influence the protein's functions.
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Affiliation(s)
- Akira Ishio
- From the Department of Biological Science and Technology, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo, 125-1500, the Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043
| | - Takeshi Sasamura
- the Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043
| | - Tomonori Ayukawa
- From the Department of Biological Science and Technology, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo, 125-1500
| | - Junpei Kuroda
- the Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043
| | - Hiroyuki O Ishikawa
- Genome and Drug Research Center, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba, 278-8510, the Graduate School of Science,Chiba University, 1-33 Yayoi, Inage, Chiba, and
| | - Naoki Aoyama
- From the Department of Biological Science and Technology, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo, 125-1500
| | - Kenjiroo Matsumoto
- the Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043
| | - Takuma Gushiken
- From the Department of Biological Science and Technology, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo, 125-1500, the Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043
| | - Tetsuya Okajima
- the Department of Biochemistry II, Nagoya University Graduate School of Medicine, Tsurumai, Showa-ku, Nagoya 466-0065, Japan
| | - Tomoko Yamakawa
- the Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043
| | - Kenji Matsuno
- the Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043,
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15
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LIF upregulates poFUT1 expression and promotes trophoblast cell migration and invasion at the fetal-maternal interface. Cell Death Dis 2014; 5:e1396. [PMID: 25165882 PMCID: PMC4454310 DOI: 10.1038/cddis.2014.335] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Revised: 07/02/2014] [Accepted: 07/03/2014] [Indexed: 12/22/2022]
Abstract
Trophoblast cell migration and invasion are crucial for the establishment of a successful pregnancy. Protein O-fucosyltransferases, such as poFUT1 and poFUT2, catalyze the O-fucosylation of proteins and have important roles in embryonic development. Leukemia inhibitory factor (LIF) is a critical cytokine in the regulation of embryonic development and implantation. However, the exact roles of poFUTs in embryo migration and invasion and the effects of LIF on the expression of poFUTs have not been studied in detail. In the current study, we showed that poFUT1 and LIF were highly expressed in human trophoblast cells and in the serum of women during the first trimester of a normal pregnancy. However, in patients with threatened abortion, poFUT1 and LIF levels were found to be reduced. There were no significant differences in the expression levels of poFUT2 between the two groups. The migration and invasion potential of trophoblasts in an explant culture and in an in vitro implantation model was decreased or increased upon altering poFUT1 expression levels by siRNA or cDNA transfection. Our results also revealed that LIF upregulated the expression of poFUT1. The upregulation of poFUT1 by LIF promoted trophoblast cell migration and invasion at the fetal–maternal interface by activating the PI3K/Akt signaling pathway. Taken together, these study findings suggest that poFUT1 may be used as a marker of embryo implantation.
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16
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Frankel WN, Mahaffey CL, McGarr TC, Beyer BJ, Letts VA. Unraveling genetic modifiers in the gria4 mouse model of absence epilepsy. PLoS Genet 2014; 10:e1004454. [PMID: 25010494 PMCID: PMC4091709 DOI: 10.1371/journal.pgen.1004454] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 05/07/2014] [Indexed: 12/24/2022] Open
Abstract
Absence epilepsy (AE) is a common type of genetic generalized epilepsy (GGE), particularly in children. AE and GGE are complex genetic diseases with few causal variants identified to date. Gria4 deficient mice provide a model of AE, one for which the common laboratory inbred strain C3H/HeJ (HeJ) harbors a natural IAP retrotransposon insertion in Gria4 that reduces its expression 8-fold. Between C3H and non-seizing strains such as C57BL/6, genetic modifiers alter disease severity. Even C3H substrains have surprising variation in the duration and incidence of spike-wave discharges (SWD), the characteristic electroencephalographic feature of absence seizures. Here we discovered extensive IAP retrotransposition in the C3H substrain, and identified a HeJ-private IAP in the Pcnxl2 gene, which encodes a putative multi-transmembrane protein of unknown function, resulting in decreased expression. By creating new Pcnxl2 frameshift alleles using TALEN mutagenesis, we show that Pcnxl2 deficiency is responsible for mitigating the seizure phenotype – making Pcnxl2 the first known modifier gene for absence seizures in any species. This finding gave us a handle on genetic complexity between strains, directing us to use another C3H substrain to map additional modifiers including validation of a Chr 15 locus that profoundly affects the severity of SWD episodes. Together these new findings expand our knowledge of how natural variation modulates seizures, and highlights the feasibility of characterizing and validating modifiers in mouse strains and substrains in the post-genome sequence era. Absence seizures - also known as “petit-mal” - define a common form of epilepsy most prevalent in children, but also seen at other ages, and in related diseases such as juvenile myoclonic epilepsy. Absence seizures cause brief periods of unconsciousness, and are accompanied by characteristic abnormal brain waves called “spike-wave discharges” (SWD) due to their appearance in the electroencephalogram (EEG). Although few genes are known for human absence seizures, perhaps because the underlying genetics are complex, several laboratory rodent models exist, including one caused by mutation of a gene called Gria4. While studying Gria4, we noticed that a mouse strain called C3H can suppress or enhance the frequency and severity of Gria4-associated SWD in a perplexing manner; such effects are generally attributed to “modifier” genes. Here we identify a novel modifier – called “pecanex-like 2”, or Pcnxl2 for short – that reduces the severity of SWD in the C3H substrain in which the Gria4 mutation originally arose. This finding directed us to use of related substrains to locate additional modifiers, one of which has an even more profound effect on SWD episodes. Modifier genes, nature's way of controlling seizure severity, are promising targets for better understanding seizure mechanisms and potential new therapies in the future.
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Affiliation(s)
- Wayne N. Frankel
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
- * E-mail:
| | | | - Tracy C. McGarr
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | - Barbara J. Beyer
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
| | - Verity A. Letts
- The Jackson Laboratory, Bar Harbor, Maine, United States of America
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17
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Liu M, Wang C, Li D, Liu Y, Sheng Q, Lv Z, Yu W, Wang D, Zhang Y, Nie Z. Cloning and expression characteristics of the notch-associated gene BmE(spl)mγ from silkworm, Bombyx mori. Appl Biochem Biotechnol 2014; 173:2065-75. [PMID: 24916802 DOI: 10.1007/s12010-014-1003-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 05/26/2014] [Indexed: 10/25/2022]
Abstract
The E(spl)mγ gene in Drosophila is a regulatory target gene downstream of the Notch pathway. BmE(spl)mγ (Bombyx mori, E(spl)mγ) is an ortholog of the Drosophila E(spl)mγ gene, and the gene encodes a protein with 248 amino acid residues. This gene was cloned and overexpressed in Escherichia coli BL21(DE3). The recombinant protein was purified and subsequently used to generate a rabbit polyclonal antibody. Western blotting analyses showed that BmE(spl)mγ expression is high in pupa and egg, and low in larva and moth. In the fifth instar larva, the protein levels are high in head, epidermis, sexual gland, trachea, and the fatbody and low in the Malpighian tubule, hemolymph, gut, and silk gland. The further immunohistochemical analyses also showed higher BmE(spl)mγ expression in the head of fifth instar larva and pupa. Of the four moth parts studied, the thorax had the highest expression level. Thus, BmE(spl)mγ might be associated with neurogenesis in silkworm. Furthermore, DAPT (a γ-secretase inhibitor and an indirect inhibitor of Notch) blocking experiments showed that higher concentrations of the blocking agent and a longer processing time reduce the transcription levels of the BmE(spl)mγ gene, demonstrating that the silkworm BmE(spl)mγ gene is associated with the Notch signal pathway. These findings suggest that the function of BmE(spl)mγ may be similar to that of its Drosophila homolog.
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Affiliation(s)
- Min Liu
- College of Life Sciences, Zhejiang Sci-Tech University, Hanghzou, 310018, China
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