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Ai N, Yu Z, Xu X, Liufu S, Wang K, Huang S, Li X, Liu X, Chen B, Ma H, Yin Y. Circular Intronic RNA circTTN Inhibits Host Gene Transcription and Myogenesis by Recruiting PURB Proteins to form Heterotypic Complexes. Int J Mol Sci 2023; 24:9859. [PMID: 37373006 DOI: 10.3390/ijms24129859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 05/24/2023] [Accepted: 06/05/2023] [Indexed: 06/29/2023] Open
Abstract
Muscle cell growth plays an important role in skeletal muscle development. Circular RNAs (circRNAs) have been proven to be involved in the regulation of skeletal muscle growth and development. In this study, we explored the effect of circTTN on myoblast growth and its possible molecular mechanism. Using C2C12 cells as a functional model, the authenticity of circTTN was confirmed by RNase R digestion and Sanger sequencing. Previous functional studies have showed that the overexpression of circTTN inhibits myoblast proliferation and differentiation. Mechanistically, circTTN recruits the PURB protein on the Titin (TTN) promoter to inhibit the expression of the TTN gene. Moreover, PURB inhibits myoblast proliferation and differentiation, which is consistent with circTTN function. In summary, our results indicate that circTTN inhibits the transcription and myogenesis of the host gene TTN by recruiting PURB proteins to form heterotypic complexes. This work may act as a reference for further research on the role of circRNA in skeletal muscle growth and development.
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Affiliation(s)
- Nini Ai
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Zonggang Yu
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Xueli Xu
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Sui Liufu
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Kaiming Wang
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Shengqiang Huang
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Xintong Li
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Xiaolin Liu
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Bohe Chen
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Haiming Ma
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Yulong Yin
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
- Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China
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2
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Scalable multiplex co-fractionation/mass spectrometry platform for accelerated protein interactome discovery. Nat Commun 2022; 13:4043. [PMID: 35831314 PMCID: PMC9279285 DOI: 10.1038/s41467-022-31809-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 06/29/2022] [Indexed: 12/14/2022] Open
Abstract
Co-fractionation/mass spectrometry (CF/MS) enables the mapping of endogenous macromolecular networks on a proteome scale, but current methods are experimentally laborious, resource intensive and afford lesser quantitative accuracy. Here, we present a technically efficient, cost-effective and reproducible multiplex CF/MS (mCF/MS) platform for measuring and comparing, simultaneously, multi-protein assemblies across different experimental samples at a rate that is up to an order of magnitude faster than previous approaches. We apply mCF/MS to map the protein interaction landscape of non-transformed mammary epithelia versus breast cancer cells in parallel, revealing large-scale differences in protein-protein interactions and the relative abundance of associated macromolecules connected with cancer-related pathways and altered cellular processes. The integration of multiplexing capability within an optimized workflow renders mCF/MS as a powerful tool for systematically exploring physical interaction networks in a comparative manner. Co-fractionation/mass spectrometry (CF/MS) allows mapping protein interactomes but efficiency and quantitative accuracy are limited. Here, the authors develop a reproducible multiplexed CF/MS method and apply it to characterize interactome rewiring in breast cancer cells.
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García-Padilla C, Muñoz-Gallardo MDM, Lozano-Velasco E, Castillo-Casas JM, Caño-Carrillo S, García-López V, Aránega A, Franco D, García-Martínez V, López-Sánchez C. New Insights into the Roles of lncRNAs as Modulators of Cytoskeleton Architecture and Their Implications in Cellular Homeostasis and in Tumorigenesis. Noncoding RNA 2022; 8:ncrna8020028. [PMID: 35447891 PMCID: PMC9033079 DOI: 10.3390/ncrna8020028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 03/31/2022] [Accepted: 04/09/2022] [Indexed: 11/20/2022] Open
Abstract
The importance of the cytoskeleton not only in cell architecture but also as a pivotal element in the transduction of signals that mediate multiple biological processes has recently been highlighted. Broadly, the cytoskeleton consists of three types of structural proteins: (1) actin filaments, involved in establishing and maintaining cell shape and movement; (2) microtubules, necessary to support the different organelles and distribution of chromosomes during cell cycle; and (3) intermediate filaments, which have a mainly structural function showing specificity for the cell type where they are expressed. Interaction between these protein structures is essential for the cytoskeletal mesh to be functional. Furthermore, the cytoskeleton is subject to intense spatio-temporal regulation mediated by the assembly and disassembly of its components. Loss of cytoskeleton homeostasis and integrity of cell focal adhesion are hallmarks of several cancer types. Recently, many reports have pointed out that lncRNAs could be critical mediators in cellular homeostasis controlling dynamic structure and stability of the network formed by cytoskeletal structures, specifically in different types of carcinomas. In this review, we summarize current information available about the roles of lncRNAs as modulators of actin dependent cytoskeleton and their impact on cancer pathogenesis. Finally, we explore other examples of cytoskeletal lncRNAs currently unrelated to tumorigenesis, to illustrate knowledge about them.
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Affiliation(s)
- Carlos García-Padilla
- Department of Human Anatomy and Embryology, Faculty of Medicine, Institute of Molecular Pathology Biomarkers, University of Extremadura, 06006 Badajoz, Spain; (E.L.-V.); (V.G.-L.); (V.G.-M.)
- Department of Experimental Biology, University of Jaen, 23071 Jaen, Spain; (M.d.M.M.-G.); (J.M.C.-C.); (S.C.-C.); (A.A.); (D.F.)
- Correspondence: (C.G.-P.); (C.L.-S.)
| | - María del Mar Muñoz-Gallardo
- Department of Experimental Biology, University of Jaen, 23071 Jaen, Spain; (M.d.M.M.-G.); (J.M.C.-C.); (S.C.-C.); (A.A.); (D.F.)
| | - Estefanía Lozano-Velasco
- Department of Human Anatomy and Embryology, Faculty of Medicine, Institute of Molecular Pathology Biomarkers, University of Extremadura, 06006 Badajoz, Spain; (E.L.-V.); (V.G.-L.); (V.G.-M.)
- Department of Experimental Biology, University of Jaen, 23071 Jaen, Spain; (M.d.M.M.-G.); (J.M.C.-C.); (S.C.-C.); (A.A.); (D.F.)
- Fundación Medina, 18016 Granada, Spain
| | - Juan Manuel Castillo-Casas
- Department of Experimental Biology, University of Jaen, 23071 Jaen, Spain; (M.d.M.M.-G.); (J.M.C.-C.); (S.C.-C.); (A.A.); (D.F.)
| | - Sheila Caño-Carrillo
- Department of Experimental Biology, University of Jaen, 23071 Jaen, Spain; (M.d.M.M.-G.); (J.M.C.-C.); (S.C.-C.); (A.A.); (D.F.)
| | - Virginio García-López
- Department of Human Anatomy and Embryology, Faculty of Medicine, Institute of Molecular Pathology Biomarkers, University of Extremadura, 06006 Badajoz, Spain; (E.L.-V.); (V.G.-L.); (V.G.-M.)
| | - Amelia Aránega
- Department of Experimental Biology, University of Jaen, 23071 Jaen, Spain; (M.d.M.M.-G.); (J.M.C.-C.); (S.C.-C.); (A.A.); (D.F.)
- Fundación Medina, 18016 Granada, Spain
| | - Diego Franco
- Department of Experimental Biology, University of Jaen, 23071 Jaen, Spain; (M.d.M.M.-G.); (J.M.C.-C.); (S.C.-C.); (A.A.); (D.F.)
- Fundación Medina, 18016 Granada, Spain
| | - Virginio García-Martínez
- Department of Human Anatomy and Embryology, Faculty of Medicine, Institute of Molecular Pathology Biomarkers, University of Extremadura, 06006 Badajoz, Spain; (E.L.-V.); (V.G.-L.); (V.G.-M.)
| | - Carmen López-Sánchez
- Department of Human Anatomy and Embryology, Faculty of Medicine, Institute of Molecular Pathology Biomarkers, University of Extremadura, 06006 Badajoz, Spain; (E.L.-V.); (V.G.-L.); (V.G.-M.)
- Correspondence: (C.G.-P.); (C.L.-S.)
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4
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Pan J, Cai X, Zheng X, Zhu X, Feng J, Wang X. Luteolin inhibits viability, migration, angiogenesis and invasion of non-small cell lung cancer vascular endothelial cells via miR-133a-3p/purine rich element binding protein B-mediated MAPK and PI3K/Akt signaling pathways. Tissue Cell 2022; 75:101740. [PMID: 35101688 DOI: 10.1016/j.tice.2022.101740] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 01/03/2022] [Accepted: 01/17/2022] [Indexed: 12/27/2022]
Abstract
Luteolin inhibits tumorigenesis of non-small cell lung cancer (NSCLC), but its mechanism still needs to be clarified. We hereby explored the effects of luteolin in vascular endothelial cells of NSCLC (NSCLC-VECs). After extraction and identification of NSCLC-VECs, cells were treated with luteolin and transfected. The viability, migration, angiogenesis and invasion of the cells were measured. The levels of miR-133a-3p, purine rich element binding protein B (PURB), vascular endothelial growth factor (VEGF), phosphatidylinositol 3-kinase (PI3K), Akt, mitogen-activated protein kinases (MAPK), matrix metalloproteinase (MMP)-2/-9 were determined. The interaction relationship of miR-133a-3p and PURB was identified. Luteolin inhibited the viability, migration, angiogenesis and invasion of NSCLC-VECs yet up-regulated miR-133a-3p level, while miR-133a-3p inhibitor counteracted the repressive effect of luteolin on the viability, migration, angiogenesis, and invasion in NSCLC-VECs. Luteolin inhibited the expressions of migration- and invasion-associated proteins (VEGF, MMP-2 and MMP-9), PI3K/Akt and MAPK signaling pathways-related factors, while miR-133a-3p inhibitor reversed the inhibitory effect of Luteolin on NSCLC-VECs. Luteolin decreased the level of PURB, which was targeted by miR-133a-3p. ShPURB promoted miR-133a-3p level in NSCLC-VECs, while reversing the promoting effects of miR-133a-3p inhibitor on the migration, invasion, and levels of migration- and invasion-associated proteins, PI3K/Akt and MAPK pathways-associated factors in NSCLC-VECs. Collectively speaking, luteolin inhibits the migration and invasion of NSCLC-VECs via miR-133a-3p/PURB- mediated MAPK and PI3K/Akt pathways.
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Affiliation(s)
- Jie Pan
- Department of General Medicine, Lishui City People's Hospital, The Sixth Affiliated Hospital of Wenzhou Medical University, The First Affiliated Hospital of Lishui University, China
| | - Xiaoping Cai
- Department of Respiratory Medicine, Lishui City People's Hospital, The Sixth Affiliated Hospital of Wenzhou Medical University, The First Affiliated Hospital of Lishui University, China
| | - Xiao Zheng
- Department of Respiratory Medicine, Suichang County People's Hospital, China
| | - Xiaoyu Zhu
- Department of General Surgery, Lishui City People's Hospital, China
| | - Jihong Feng
- Department of Oncology, Lishui City People's Hospital, The Sixth Affiliated Hospital of Wenzhou Medical University, The First Affiliated Hospital of Lishui University, China
| | - Xiaoqiu Wang
- Department of Oncology, Lishui City People's Hospital, The Sixth Affiliated Hospital of Wenzhou Medical University, The First Affiliated Hospital of Lishui University, China.
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5
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Lymphoid Organ Proteomes Identify Therapeutic Efficacy Biomarkers Following the Intracavitary Administration of Curcumin in a Highly Invasive Rat Model of Peritoneal Mesothelioma. Int J Mol Sci 2021; 22:ijms22168566. [PMID: 34445271 PMCID: PMC8395293 DOI: 10.3390/ijms22168566] [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: 06/10/2021] [Revised: 07/30/2021] [Accepted: 08/05/2021] [Indexed: 12/16/2022] Open
Abstract
This study aimed to identify the proteomic changes produced by curcumin treatment following stimulation of the host immune system in a rat model of malignant mesothelioma. We analyzed the proteomes of secondary lymphoid organs from four normal rats, four untreated tumor-bearing rats, and four tumor-bearing rats receiving repeated intraperitoneal administrations of curcumin. Cross-comparing proteome analyses of histological sections of the spleen from the three groups first identified a list of eighty-three biomarkers of interest, thirteen of which corresponded to proteins already reported in the literature and involved in the anticancer therapeutic effects of curcumin. In a second step, comparing these data with proteomic analyses of histological sections of mesenteric lymph nodes revealed eight common biomarkers showing a similar pattern of changes in both lymphoid organs. Additional findings included a partial reduction of the increase in spleen-circulating biomarkers, a decrease in C-reactive protein and complement C3 in the spleen and lymph nodes, and an increase in lymph node purine nucleoside phosphorylase previously associated with liver immunodeficiency. Our results suggest some protein abundance changes could be related to the systemic, distant non-target antitumor effects produced by this phytochemical.
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Chang KC, Diermeier SD, Yu AT, Brine LD, Russo S, Bhatia S, Alsudani H, Kostroff K, Bhuiya T, Brogi E, Pappin DJ, Bennett CF, Rigo F, Spector DL. MaTAR25 lncRNA regulates the Tensin1 gene to impact breast cancer progression. Nat Commun 2020; 11:6438. [PMID: 33353933 PMCID: PMC7755919 DOI: 10.1038/s41467-020-20207-y] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 11/20/2020] [Indexed: 12/31/2022] Open
Abstract
Misregulation of long non-coding RNA (lncRNA) genes has been linked to a wide variety of cancer types. Here we report on Mammary Tumor Associated RNA 25 (MaTAR25), a nuclear enriched and chromatin associated lncRNA that plays a role in mammary tumor cell proliferation, migration, and invasion, both in vitro and in vivo. MaTAR25 functions by interacting with purine rich element binding protein B (PURB), and associating with a major downstream target gene Tensin1 (Tns1) to regulate its expression in trans. The Tns1 protein product is a critical component of focal adhesions linking signaling between the extracellular matrix and the actin cytoskeleton. Knockout of MaTAR25 results in down-regulation of Tns1 leading to a reorganization of the actin cytoskeleton, and a reduction of focal adhesions and microvilli. We identify LINC01271 as the human ortholog of MaTAR25, and importantly, increased expression of LINC01271 is associated with poor patient prognosis and metastasis. Our findings demonstrate that LINC01271 represents a potential therapeutic target to alter breast cancer progression.
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Affiliation(s)
- Kung-Chi Chang
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, New York, USA
- Molecular and Cellular Biology Program, Stony Brook University, Stony Brook, NY, 11794, USA
| | - Sarah D Diermeier
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, New York, USA
- Department of Biochemistry, University of Otago, Dunedin, 9016, New Zealand
| | - Allen T Yu
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, New York, USA
- Genetics Program, Stony Brook University, Stony Brook, NY, 11794, USA
| | - Lily D Brine
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, New York, USA
| | - Suzanne Russo
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, New York, USA
| | - Sonam Bhatia
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, New York, USA
| | - Habeeb Alsudani
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, New York, USA
| | - Karen Kostroff
- Department of Surgical Oncology, Northwell Health, Lake Success, NY, 11042, USA
| | - Tawfiqul Bhuiya
- Department of Pathology, Northwell Health, Lake Success, NY, 11042, USA
| | - Edi Brogi
- Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Darryl J Pappin
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, New York, USA
| | | | - Frank Rigo
- Ionis Pharmaceuticals, Carlsbad, CA, 92010, USA
| | - David L Spector
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, 11724, New York, USA.
- Molecular and Cellular Biology Program, Stony Brook University, Stony Brook, NY, 11794, USA.
- Genetics Program, Stony Brook University, Stony Brook, NY, 11794, USA.
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Gao J, Tian L, Sun Y, Li W, Zhao L, Sun Y, Jing Z, Zhou L, Liu F, Zhao X. PURα mediates epithelial-mesenchymal transition to promote esophageal squamous cell carcinoma progression by regulating Snail2. Cancer Lett 2020; 498:98-110. [PMID: 33144099 DOI: 10.1016/j.canlet.2020.10.030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Revised: 10/17/2020] [Accepted: 10/21/2020] [Indexed: 01/04/2023]
Abstract
Esophageal squamous cell carcinoma (ESCC) is one of the most common lethal cancers in the world. Dysregulation of purine-rich element binding protein alpha (PURα), which contributes to the initiation of PURΑ syndrome, is reportedly involved in the progression of multiple cancers, but its function and underlying mechanisms in ESCC progression remain unclear. Here, we first demonstrated that PURα promoted cell growth, migration and invasion in ESCC both in vitro and in vivo. An immunohistochemistry assay was then performed on 225 ESCC tissues, showing that high PURα expression was positively associated with lymph node metastasis and the AJCC stage, and the ESCC patients with positive PURα expression had worse survival. In addition, RNA sequencing implied that PURα induced epithelial-mesenchymal transition (EMT) in ESCC, which was further confirmed by qPCR, Western blotting and immunofluorescence analyses. Mechanistically, PURα enhanced the transcription of Snail2 by binding to its promoter region. Knockdown of Snail2 reversed PURα-induced EMT and inhibited the migration and invasion of ESCC cells. In conclusion, this study indicated that PURα promotes Snail2 transcriptional activity to induce EMT during ESCC progression.
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Affiliation(s)
- Jiajia Gao
- State Key Laboratory of Molecular Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Lusong Tian
- State Key Laboratory of Molecular Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Yulin Sun
- State Key Laboratory of Molecular Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Wei Li
- State Key Laboratory of Molecular Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Lina Zhao
- State Key Laboratory of Molecular Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Yan Sun
- State Key Laboratory of Molecular Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Zongpan Jing
- State Key Laboratory of Molecular Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Lanping Zhou
- State Key Laboratory of Molecular Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Fang Liu
- State Key Laboratory of Molecular Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Xiaohang Zhao
- State Key Laboratory of Molecular Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
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Ferris LA, Kelm RJ. Structural and functional analysis of single-nucleotide polymorphic variants of purine-rich element-binding protein B. J Cell Biochem 2018; 120:5835-5851. [PMID: 30387171 DOI: 10.1002/jcb.27869] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 09/20/2018] [Indexed: 12/14/2022]
Abstract
Purine-rich element-binding protein B (Purβ) inhibits myofibroblast differentiation by repressing the expression of the smooth muscle α-actin gene (Acta2). Several reports have identified the structural domains in Purβ that enable its characteristic interaction with purine-rich single-stranded DNA (ssDNA) sequences in the Acta2 promoter. However, little is known about the physical and functional effects of single-nucleotide polymorphisms that alter individual amino acid residues in Purβ. This study evaluated seven rare single amino acid variants of human PURB engineered into the homologous mouse Purβ protein. Mapping the location of variant residues on a homology model of the Purβ homodimer suggested that most of the altered residues are remote from the predicted ssDNA-binding regions of the protein. The repressor activity of each Purβ variant was assessed in transfected fibroblasts and smooth muscle cells via Acta2 promoter-reporter assays. A Q64* nonsense variant was completely inactive while missense variants exhibited repressor activity that ranged from ~1.5-fold greater to ~2-fold less than wild-type Purβ. Lower activity variants P223L and R297Q were expressed in bacteria and purified to homogeneity. Each variant was physically indistinguishable from wild-type Purβ in terms of quaternary structure and thermostability. Results of DNA and protein-binding assays indicated that the P223L and R297Q variants retained high affinity and specificity for purine-rich ssDNA sequences but differed in their interaction with other Acta2 regulatory proteins. These findings suggest that the presence of certain variant residues affects the Acta2 repressor activity of Purβ by altering its interaction with other transcription factors but not with ssDNA.
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Affiliation(s)
- Lauren A Ferris
- Department of Biochemistry, University of Vermont, Robert Larner, M. D. College of Medicine, Burlington, Vermont
| | - Robert J Kelm
- Department of Biochemistry, University of Vermont, Robert Larner, M. D. College of Medicine, Burlington, Vermont
- Department of Medicine, Division of Cardiovascular Medicine, University of Vermont, Robert Larner, M. D. College qof Medicine, Burlington, Vermont
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9
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Huo N, Yu M, Li X, Zhou C, Jin X, Gao X. PURB is a positive regulator of amino acid‐induced milk synthesis in bovine mammary epithelial cells. J Cell Physiol 2018; 234:6992-7003. [DOI: 10.1002/jcp.27452] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 08/29/2018] [Indexed: 12/11/2022]
Affiliation(s)
- Nan Huo
- The Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University Harbin China
| | - Mengmeng Yu
- The Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University Harbin China
| | - Xueying Li
- The Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University Harbin China
| | - Chenjian Zhou
- The Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University Harbin China
| | - Xin Jin
- The Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University Harbin China
| | - Xuejun Gao
- The Key Laboratory of Dairy Science of Education Ministry, Northeast Agricultural University Harbin China
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