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Rojas ML, Muñoz JP, Flores-Martín J, Sànchez-Fernàndez-de-Landa P, Cruz Del Puerto M, Genti-Raimondi S, Zorzano A. StarD7 deficiency switches on glycolysis and promotes mitophagy flux in C2C12 myoblasts. FEBS J 2024; 291:338-357. [PMID: 37846201 DOI: 10.1111/febs.16979] [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: 05/03/2023] [Revised: 09/01/2023] [Accepted: 10/13/2023] [Indexed: 10/18/2023]
Abstract
StarD7 is a member of the START protein family required for phosphatidylcholine delivery to the mitochondria, thus key to maintain mitochondrial structure. Its deficiency has been associated with an impairment of cellular processes, such as proliferation and migration, and it has also been reported that it is needed in myogenic differentiation. Here, we show that StarD7 deficiency in C2C12 muscle cells results in the accumulation of abnormal mitochondria, a reduced number of mitochondria per cell area and increased glycolysis. In addition, StarD7-deficient cells undergo an increase in mitochondria-ER contact sites, reduced connexin 43 expression, and disturbances in lipid handling, evidenced by lipid droplet accumulation and decreased levels in phosphatidylserine synthase 1 and 2 expression. Interestingly, StarD7-deficient cells showed alterations in mitophagy markers. We observed accumulation of LC3B-II and BNIP3 proteins in mitochondria-enriched fractions and accumulation of autophagolysosomal and lysosomal vesicles in StarD7-deficient cells. Furthermore, live-cell imaging experiments of StarD7 knockdown cells expressing mitochondria-targeted mKeima indicated an enhanced mitochondria delivery into lysosomes. Importantly, StarD7 reconstitution in StarD7-deficient cells restores LC3B-II expression in mitochondria-enriched fractions at similar levels to those observed in control cells. Collectively, these findings suggest that StarD7-deficient C2C12 myoblasts are associated with altered cristae structure, disturbances in neutral lipid accumulation, glucose metabolism, and increased mitophagy flux. The alterations mentioned above allow for the maintenance of mitochondrial function.
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Affiliation(s)
- María L Rojas
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Córdoba, Argentina
| | - Juan Pablo Muñoz
- Institut d' Investigació Biomèdica (IIB) Sant Pau, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain
| | - Jésica Flores-Martín
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Córdoba, Argentina
| | - Paula Sànchez-Fernàndez-de-Landa
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Spain
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Spain
| | - Mariano Cruz Del Puerto
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Córdoba, Argentina
| | - Susana Genti-Raimondi
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Córdoba, Argentina
| | - Antonio Zorzano
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, Madrid, Spain
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Spain
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, Spain
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2
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Zhao YQ, Jin HR, Kim D, Jung SH, Liu S, Wan J, Lo HY, Fu XQ, Wang Q, Hao C, Bellail AC. SUMO1 degrader induces ER stress and ROS accumulation through deSUMOylation of TCF4 and inhibition of its transcription of StarD7 in colon cancer. Mol Carcinog 2023; 62:1249-1262. [PMID: 37191369 PMCID: PMC10524896 DOI: 10.1002/mc.23560] [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: 11/16/2022] [Revised: 02/09/2023] [Accepted: 05/04/2023] [Indexed: 05/17/2023]
Abstract
Small molecule degraders of small ubiquitin-related modifier 1 (SUMO1) induce SUMO1 degradation in colon cancer cells and inhibits the cancer cell growth; however, it is unclear how SUMO1 degradation leads to the anticancer activity of the degraders. Genome-wide CRISPR-Cas9 knockout screen has identified StAR-related lipid transfer domain containing 7 (StarD7) as a critical gene for the degrader's anticancer activity. Here, we show that both StarD7 mRNA and protein are overexpressed in human colon cancer and its knockout significantly reduces colon cancer cell growth and xenograft progression. The treatment with the SUMO1 degrader lead compound HB007 reduces StarD7 mRNA and protein levels and increases endoplasmic reticulum (ER) stress and reactive oxygen species (ROS) production in colon cancer cells and three-dimensional (3D) organoids. The study further provides a novel mechanism of the compound anticancer activity that SUMO1 degrader-induced decrease of StarD7 occur through degradation of SUMO1, deSUMOylation and degradation of T cell-specific transcription 4 (TCF4) and thereby inhibition of its transcription of StarD7 in colon cancer cells, 3D organoids and patient-derived xenografts (PDX).
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Affiliation(s)
- Yin Quan Zhao
- Department of Gastric and Colorectal Surgery, General Surgery Center, The First Hospital of Jilin University, Changchun, Jilin Province, 130021, China
- School of Life Sciences, Jilin University, Changchun, Jilin Province, 130012, China
- Department of Pathology & Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Hong Ri Jin
- Department of Pathology & Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Daeho Kim
- Department of Pathology & Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Sung Han Jung
- Department of Pathology & Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Sheng Liu
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Jun Wan
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Ho-Yin Lo
- Synovel Laboratory LLC, Danbury, CT 06811, USA
| | - Xue Qi Fu
- School of Life Sciences, Jilin University, Changchun, Jilin Province, 130012, China
| | - Quan Wang
- Department of Gastric and Colorectal Surgery, General Surgery Center, The First Hospital of Jilin University, Changchun, Jilin Province, 130021, China
| | - Chunhai Hao
- Department of Pathology & Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Anita C. Bellail
- Department of Pathology & Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- HB Therapeutics Inc. Indianapolis, IN 46202, USA
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3
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Cruz Del Puerto M, Rojas ML, Racca AC, Kourdova LT, Miranda AL, Panzetta-Dutari G, Genti-Raimondi S, Flores-Martín JB. StarD7 deficiency hinders cell motility through p-ERK1/2/Cx43 reduction. PLoS One 2022; 17:e0279912. [PMID: 36584213 PMCID: PMC9803278 DOI: 10.1371/journal.pone.0279912] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 12/18/2022] [Indexed: 01/01/2023] Open
Abstract
StarD7 belongs to START protein family involved in lipid traffic, metabolism, and signaling events. Its precursor, StarD7.I which is important for mitochondrial homeostasis, is processed to the StarD7.II isoform that lacks the mitochondrial targeting sequence and is mainly released to the cytosol. StarD7 knockdown interferes with cell migration by an unknown mechanism. Here, we demonstrate that StarD7 silencing decreased connexin 43 (Cx43), integrin β1, and p-ERK1/2 expression in the non-tumoral migratory HTR-8/SVneo cells. StarD7-deficient cells exhibited Golgi disruption and reduced competence to reorient the microtubule-organizing center. The migratory capacity of StarD7-silenced cells was reestablished when Cx43 level was resettled, while p-ERK1/2 expression remained low. Importantly, ectopic expression of the StarD7.II isoform not only restored cell migration but also ERK1/2, Cx43, and integrin β1 expression. Thus, StarD7 is implicated in cell migration through an ERK1/2/Cx43 dependent mechanism but independent of the StarD7.I function in the mitochondria.
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Affiliation(s)
- Mariano Cruz Del Puerto
- Departamento de Bioquímica Clínica, Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Ciudad Universitaria, Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Ciudad Universitaria, Córdoba, Argentina
| | - María Laura Rojas
- Departamento de Bioquímica Clínica, Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Ciudad Universitaria, Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Ciudad Universitaria, Córdoba, Argentina
| | - Ana Cristina Racca
- Departamento de Bioquímica Clínica, Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Ciudad Universitaria, Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Ciudad Universitaria, Córdoba, Argentina
| | - Lucille Tihomirova Kourdova
- Departamento de Bioquímica Clínica, Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Ciudad Universitaria, Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Ciudad Universitaria, Córdoba, Argentina
| | - Andrea Lis Miranda
- Departamento de Bioquímica Clínica, Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Ciudad Universitaria, Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Ciudad Universitaria, Córdoba, Argentina
| | - Graciela Panzetta-Dutari
- Departamento de Bioquímica Clínica, Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Ciudad Universitaria, Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Ciudad Universitaria, Córdoba, Argentina
| | - Susana Genti-Raimondi
- Departamento de Bioquímica Clínica, Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Ciudad Universitaria, Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Ciudad Universitaria, Córdoba, Argentina
| | - Jésica Belén Flores-Martín
- Departamento de Bioquímica Clínica, Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Ciudad Universitaria, Córdoba, Argentina
- Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Ciudad Universitaria, Córdoba, Argentina
- * E-mail:
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4
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Asif K, Memeo L, Palazzolo S, Frión-Herrera Y, Parisi S, Caligiuri I, Canzonieri V, Granchi C, Tuccinardi T, Rizzolio F. STARD3: A Prospective Target for Cancer Therapy. Cancers (Basel) 2021; 13:4693. [PMID: 34572920 PMCID: PMC8472075 DOI: 10.3390/cancers13184693] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 09/10/2021] [Indexed: 12/24/2022] Open
Abstract
Cancer is one of the major causes of death in developed countries and current therapies are based on surgery, chemotherapeutic agents, and radiation. To overcome side effects induced by chemo- and radiotherapy, in recent decades, targeted therapies have been proposed in second and even first lines. Targeted drugs act on the essential pathways involved in tumor induction, progression, and metastasis, basically all the hallmark of cancers. Among emerging pathways, the cholesterol metabolic pathway is a strong candidate for this purpose. Cancer cells have an accelerated metabolic rate and require a continuous supply of cholesterol for cell division and membrane renewal. Steroidogenic acute regulatory related lipid transfer (START) proteins are a family of proteins involved in the transfer of lipids and some of them are important in non-vesicular cholesterol transportation within the cell. The alteration of their expression levels is implicated in several diseases, including cancers. In this review, we report the latest discoveries on StAR-related lipid transfer protein domain 3 (STARD3), a member of the START family, which has a potential role in cancer, focusing on the structural and biochemical characteristics and mechanisms that regulate its activity. The role of the STARD3 protein as a molecular target for the development of cancer therapies is also discussed. As STARD3 is a key protein in the cholesterol movement in cancer cells, it is of interest to identify inhibitors able to block its activity.
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Affiliation(s)
- Kanwal Asif
- Department of Molecular Sciences and Nanosystems, PhD School in Science and Technology of Bio and Nanomaterials, Ca’ Foscari University of Venice, 30172 Venice, Italy;
- Pathology Unit, Centro di Riferimento Oncologico di Aviano (C.R.O.) IRCCS, 33081 Aviano, Italy; (S.P.); (S.P.); (V.C.)
| | - Lorenzo Memeo
- Department of Experimental Oncology, Mediterranean Institute of Oncology, 95029 Catania, Italy;
| | - Stefano Palazzolo
- Pathology Unit, Centro di Riferimento Oncologico di Aviano (C.R.O.) IRCCS, 33081 Aviano, Italy; (S.P.); (S.P.); (V.C.)
| | - Yahima Frión-Herrera
- Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, 30172 Venice, Italy; or
| | - Salvatore Parisi
- Pathology Unit, Centro di Riferimento Oncologico di Aviano (C.R.O.) IRCCS, 33081 Aviano, Italy; (S.P.); (S.P.); (V.C.)
| | - Isabella Caligiuri
- Pathology Unit, Centro di Riferimento Oncologico di Aviano (C.R.O.) IRCCS, 33081 Aviano, Italy; (S.P.); (S.P.); (V.C.)
| | - Vincenzo Canzonieri
- Pathology Unit, Centro di Riferimento Oncologico di Aviano (C.R.O.) IRCCS, 33081 Aviano, Italy; (S.P.); (S.P.); (V.C.)
- Department of Medical, Surgical and Health Sciences, University of Trieste, 34149 Trieste, Italy
| | - Carlotta Granchi
- Department of Pharmacy, University of Pisa, 56126 Pisa, Italy; (C.G.); (T.T.)
| | - Tiziano Tuccinardi
- Department of Pharmacy, University of Pisa, 56126 Pisa, Italy; (C.G.); (T.T.)
| | - Flavio Rizzolio
- Pathology Unit, Centro di Riferimento Oncologico di Aviano (C.R.O.) IRCCS, 33081 Aviano, Italy; (S.P.); (S.P.); (V.C.)
- Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, 30172 Venice, Italy; or
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5
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Sampieri L, Funes Chabán M, Di Giusto P, Rozés-Salvador V, Alvarez C. CREB3L2 Modulates Nerve Growth Factor-Induced Cell Differentiation. Front Mol Neurosci 2021; 14:650338. [PMID: 34421533 PMCID: PMC8370844 DOI: 10.3389/fnmol.2021.650338] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 06/24/2021] [Indexed: 11/13/2022] Open
Abstract
Nerve growth factor (NGF) stimulates numerous cellular physiological processes, including growth, differentiation, and survival, and maintains the phenotype of several neuronal types. Most of these NGF-induced processes require adaptation of the secretory pathway since they involve extensive remodeling of membranes and protein redistribution along newly formed neuritic processes. CREB3 transcription factors have emerged as signaling hubs for the regulation of numerous genes involved in the secretory pathway and Golgi homeostasis, integrating stimuli from multiple sources to control secretion, posttranslational modifications and trafficking of proteins. Although recent studies have focused on their role in the central nervous system, little is known about their participation in cell differentiation. Therefore, we aimed to analyze the expression and signaling mechanism of CREB3 transcription factor family members, using the NGF-induced PC12 cell differentiation model. Results show that NGF treatment causes Golgi enlargement and a parallel increased expression of proteins and mRNAs encoding for proteins required for membrane transport (transport factors). Additionally, a significant increase in CREB3L2 protein and mRNA levels is detected in response to NGF. Both MAPK and cAMP signaling pathways are required for this response. Interestingly, CREB3L2 overexpression hampers the NGF-induced neurite outgrowth while its inhibition enhances the morphological changes driven by NGF. In agreement, CREB3L2 overexpressing cells display higher immunofluorescence intensity of Rab5 GTPase (a negative regulator of PC12 differentiation) than control cells. Also, Rab5 immunofluorescence levels decrease in CREB3L2-depleted cells. Taken together, our findings imply that CREB3L2 is an important downstream effector of NGF-activated pathways, leading to neuronal differentiation.
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Affiliation(s)
- Luciana Sampieri
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Córdoba, Argentina.,Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Macarena Funes Chabán
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Córdoba, Argentina.,Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Pablo Di Giusto
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Córdoba, Argentina.,Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Victoria Rozés-Salvador
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Cecilia Alvarez
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Córdoba, Argentina.,Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
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6
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Rojas ML, Cruz Del Puerto MM, Flores-Martín J, Racca AC, Kourdova LT, Miranda AL, Panzetta-Dutari GM, Genti-Raimondi S. Role of the lipid transport protein StarD7 in mitochondrial dynamics. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:159029. [PMID: 34416390 DOI: 10.1016/j.bbalip.2021.159029] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 07/16/2021] [Accepted: 08/13/2021] [Indexed: 10/20/2022]
Abstract
Mitochondria are dynamic organelles crucial for cell function and survival implicated in oxidative energy production whose central functions are tightly controlled by lipids. StarD7 is a lipid transport protein involved in the phosphatidylcholine (PC) delivery to mitochondria. Previous studies have shown that StarD7 knockdown induces alterations in mitochondria and endoplasmic reticulum (ER) with a reduction in PC content, however whether StarD7 modulates mitochondrial dynamics remains unexplored. Here, we generated HTR-8/SVneo stable cells expressing the precursor StarD7.I and the mature processed StarD7.II isoforms. We demonstrated that StarD7.I overexpression altered mitochondrial morphology increasing its fragmentation, whereas no changes were observed in StarD7.II-overexpressing cells compared to the control (Ct) stable cells. StarD7.I (D7.I) stable cells were able to transport higher fluorescent PC analog to mitochondria than Ct cells, yield mitochondrial fusions, maintained the membrane potential, and produced lower levels of reactive oxygen species (ROS). Additionally, the expression of Dynamin Related Protein 1 (Drp1) and Mitofusin (Mfn2) proteins were increased, whereas the amount of Mitofusin 1 (Mfn1) decreased. Moreover, transfections with plasmids encoding Drp1-K38A, Drp1-S637D or Drp1-S637A mutants indicated that mitochondrial fragmentation in D7.I cells occurs in a fission-dependent manner via Drp1. In contrast, StarD7 silencing decreased Mfn1 and Mfn2 fusion proteins without modification of Drp1 protein level. These cells increased ROS levels and presented donut-shape mitochondria, indicative of metabolic stress. Altogether our findings provide novel evidence indicating that alterations in StarD7.I expression produce significant changes in mitochondrial morphology and dynamics.
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Affiliation(s)
- María L Rojas
- Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Bioquímica Clínica, Ciudad Universitaria, X5000HUA Córdoba, Argentina; Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Ciudad Universitaria, X5000HUA Córdoba, Argentina
| | - Mariano M Cruz Del Puerto
- Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Bioquímica Clínica, Ciudad Universitaria, X5000HUA Córdoba, Argentina; Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Ciudad Universitaria, X5000HUA Córdoba, Argentina
| | - Jésica Flores-Martín
- Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Bioquímica Clínica, Ciudad Universitaria, X5000HUA Córdoba, Argentina; Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Ciudad Universitaria, X5000HUA Córdoba, Argentina
| | - Ana C Racca
- Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Bioquímica Clínica, Ciudad Universitaria, X5000HUA Córdoba, Argentina; Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Ciudad Universitaria, X5000HUA Córdoba, Argentina
| | - Lucille T Kourdova
- Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Bioquímica Clínica, Ciudad Universitaria, X5000HUA Córdoba, Argentina; Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Ciudad Universitaria, X5000HUA Córdoba, Argentina
| | - Andrea L Miranda
- Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Bioquímica Clínica, Ciudad Universitaria, X5000HUA Córdoba, Argentina; Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Ciudad Universitaria, X5000HUA Córdoba, Argentina
| | - Graciela M Panzetta-Dutari
- Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Bioquímica Clínica, Ciudad Universitaria, X5000HUA Córdoba, Argentina; Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Ciudad Universitaria, X5000HUA Córdoba, Argentina
| | - Susana Genti-Raimondi
- Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Bioquímica Clínica, Ciudad Universitaria, X5000HUA Córdoba, Argentina; Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Ciudad Universitaria, X5000HUA Córdoba, Argentina.
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7
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Clark BJ. The START-domain proteins in intracellular lipid transport and beyond. Mol Cell Endocrinol 2020; 504:110704. [PMID: 31927098 DOI: 10.1016/j.mce.2020.110704] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 01/08/2020] [Accepted: 01/08/2020] [Indexed: 12/17/2022]
Abstract
The Steroidogenic Acute Regulatory Protein-related Lipid Transfer (START) domain is a ~210 amino acid sequence that folds into an α/β helix-grip structure forming a hydrophobic pocket for lipid binding. The helix-grip fold structure defines a large superfamily of proteins, and this review focuses on the mammalian START domain family members that include single START domain proteins with identified ligands, and larger multi-domain proteins that may have novel roles in metabolism. Much of our understanding of the mammalian START domain proteins in lipid transport and changes in metabolism has advanced through studies using knockout mouse models, although for some of these proteins the identity and/or physiological role of ligand binding remains unknown. The findings that helped define START domain lipid-binding specificity, lipid transport, and changes in metabolism are presented to highlight that fundamental questions remain regarding the biological function(s) for START domain-containing proteins.
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Affiliation(s)
- Barbara J Clark
- Department of Biochemistry & Molecular Genetics, University of Louisville School of Medicine, Louisville, KY, 40292, USA.
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8
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Ullah I, Paul S, Hong Z, Wang YG. Significance tests for analyzing gene expression data with small sample sizes. Bioinformatics 2019; 35:3996-4003. [PMID: 30874796 DOI: 10.1093/bioinformatics/btz189] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Revised: 02/20/2019] [Accepted: 03/13/2019] [Indexed: 11/12/2022] Open
Abstract
MOTIVATION Under two biologically different conditions, we are often interested in identifying differentially expressed genes. It is usually the case that the assumption of equal variances on the two groups is violated for many genes where a large number of them are required to be filtered or ranked. In these cases, exact tests are unavailable and the Welch's approximate test is most reliable one. The Welch's test involves two layers of approximations: approximating the distribution of the statistic by a t-distribution, which in turn depends on approximate degrees of freedom. This study attempts to improve upon Welch's approximate test by avoiding one layer of approximation. RESULTS We introduce a new distribution that generalizes the t-distribution and propose a Monte Carlo based test that uses only one layer of approximation for statistical inferences. Experimental results based on extensive simulation studies show that the Monte Carol based tests enhance the statistical power and performs better than Welch's t-approximation, especially when the equal variance assumption is not met and the sample size of the sample with a larger variance is smaller. We analyzed two gene-expression datasets, namely the childhood acute lymphoblastic leukemia gene-expression dataset with 22 283 genes and Golden Spike dataset produced by a controlled experiment with 13 966 genes. The new test identified additional genes of interest in both datasets. Some of these genes have been proven to play important roles in medical literature. AVAILABILITY AND IMPLEMENTATION R scripts and the R package mcBFtest is available in CRAN and to reproduce all reported results are available at the GitHub repository, https://github.com/iullah1980/MCTcodes. SUPPLEMENTARY INFORMATION Supplementary data is available at Bioinformatics online.
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Affiliation(s)
- Insha Ullah
- School of Mathematical Sciences, Queensland University of Technology, Brisbane, QLD, Australia
| | - Sudhir Paul
- Department of Mathematics and Statistics, University of Windsor, Windsor, ON, Canada
| | - Zhenjie Hong
- College of Mathematics and Physics, Wenzhou University, Wenzhou, Zhejiang, China
| | - You-Gan Wang
- School of Mathematical Sciences, Queensland University of Technology, Brisbane, QLD, Australia
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9
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Flores-Martín J, Reyna L, Cruz Del Puerto M, Rojas ML, Panzetta-Dutari GM, Genti-Raimondi S. Hexosamine pathway regulates StarD7 expression in JEG-3 cells. Mol Biol Rep 2018; 45:2593-2600. [PMID: 30315445 DOI: 10.1007/s11033-018-4428-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 10/05/2018] [Indexed: 11/29/2022]
Abstract
StarD7 is a lipid binding protein involved in the delivery of phosphatidylcholine to the mitochondria whose promoter is activated by Wnt/β-catenin signaling. Although the majority of glucose enters glycolysis, ~ 2-5% of it can be metabolized via the hexosamine biosynthetic pathway (HBP). Considering that HBP has been implicated in the regulation of β-catenin we explored if changes in glucose levels modulate StarD7 expression by the HBP in trophoblast cells. We found an increase in StarD7 as well as in β-catenin expression following high-glucose (25 mM) treatment in JEG-3 cells; these effects were abolished in the presence of HBP inhibitors. Moreover, since HBP is able to promote unfolded protein response (UPR) the protein levels of GRP78, Ire1α, calnexin, p-eIF2α and total eIF2α as well as XBP1 mRNA was measured. Our results indicate that a diminution in glucose concentration leads to a decrease in StarD7 expression and an increase in the UPR markers: GRP78 and Ire1α. Conversely, an increase in glucose is associated to high StarD7 levels and low GRP78 expression, phospho-eIF2α and XBP1 splicing, although Ire1α remains high when cells are restored to high glucose. Taken together these findings indicate that glucose modulates StarD7 and β-catenin expression through the HBP associated to UPR, suggesting the existence of a link between UPR and HBP in trophoblast cells. This is the first study reporting the effects of glucose on StarD7 in trophoblast cells. These data highlight the importance to explore the role of StarD7 in placenta disorders related to nutrient availability.
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Affiliation(s)
- Jésica Flores-Martín
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA, Córdoba, Argentina.,Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Ciudad Universitaria, X5000HUA, Córdoba, Argentina
| | - Luciana Reyna
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA, Córdoba, Argentina.,Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Ciudad Universitaria, X5000HUA, Córdoba, Argentina
| | - Mariano Cruz Del Puerto
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA, Córdoba, Argentina.,Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Ciudad Universitaria, X5000HUA, Córdoba, Argentina
| | - María L Rojas
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA, Córdoba, Argentina.,Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Ciudad Universitaria, X5000HUA, Córdoba, Argentina
| | - Graciela M Panzetta-Dutari
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA, Córdoba, Argentina.,Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Ciudad Universitaria, X5000HUA, Córdoba, Argentina
| | - Susana Genti-Raimondi
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, X5000HUA, Córdoba, Argentina. .,Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), Ciudad Universitaria, X5000HUA, Córdoba, Argentina. .,Departamento de Bioquímica Clínica, CIBICI-CONICET, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, X5000HUA, Córdoba, Argentina.
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10
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Identification of the N-terminal transmembrane domain of StarD7 and its importance for mitochondrial outer membrane localization and phosphatidylcholine transfer. Sci Rep 2017; 7:8793. [PMID: 28821867 PMCID: PMC5562819 DOI: 10.1038/s41598-017-09205-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 07/24/2017] [Indexed: 11/08/2022] Open
Abstract
StarD7 facilitates phosphatidylcholine (PC) transfer to mitochondria, and is essential for mitochondrial homeostasis. However, the molecular mechanism for PC transfer by protein remains poorly understood. Herein, we describe a putative novel transmembrane (TM) domain C-terminal to the mitochondria-targeting signal (MTS) sequence at the N-terminus of StarD7. The mature form of StarD7 is integrated and/or associated onto the outer leaflet of the outer mitochondrial membrane (OMM) in HEPA-1 and HepG2 cells. A truncated form of StarD7 lacking the TM domain is distributed in the inner space of the mitochondria, and cannot reverse mitochondrial abnormalities, such as complex formation and PC content, when re-expressed in StarD7-KO HEPA-1 cells. Re-expression of wild StarD7 can compensate these mitochondrial functions of StarD7-KO HEPA-1 cells. The precursor form of StarD7 is cleaved between Met76 and Ala77, and Ala77 and Ala78 in the TM domain to produce the mature form. These results suggest that StarD7 is anchored onto the OMM through its N-terminal TM domain, and the C-terminal START domain may extend into the cytoplasm and shuttle PC between the ER and OMM at the ER-mitochondria contact sites.
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11
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Yang L, Na CL, Luo S, Wu D, Hogan S, Huang T, Weaver TE. The Phosphatidylcholine Transfer Protein Stard7 is Required for Mitochondrial and Epithelial Cell Homeostasis. Sci Rep 2017; 7:46416. [PMID: 28401922 PMCID: PMC5388865 DOI: 10.1038/srep46416] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 03/15/2017] [Indexed: 12/15/2022] Open
Abstract
Mitochondria synthesize select phospholipids but lack the machinery for synthesis of the most abundant mitochondrial phospholipid, phosphatidylcholine (PC). Although the phospholipid transfer protein Stard7 promotes uptake of PC by mitochondria, the importance of this pathway for mitochondrial and cellular homeostasis represents a significant knowledge gap. Haploinsufficiency for Stard7 is associated with significant exacerbation of allergic airway disease in mice, including an increase in epithelial barrier permeability. To test the hypothesis that Stard7 deficiency leads to altered barrier structure/function downstream of mitochondrial dysfunction, Stard7 expression was knocked down in a bronchiolar epithelial cell line (BEAS-2B) and specifically deleted in lung epithelial cells of mice (Stard7epi∆/∆). Stard7 deficiency was associated with altered mitochondrial size and membrane organization both in vitro and in vivo. Altered mitochondrial structure was accompanied by disruption of mitochondrial homeostasis, including decreased aerobic respiration, increased oxidant stress, and mitochondrial DNA damage that, in turn, was linked to altered barrier integrity and function. Both mitochondrial and barrier defects were largely corrected by targeting Stard7 to mitochondria or treating epithelial cells with a mitochondrial-targeted antioxidant. These studies suggest that Stard7-mediated transfer of PC is crucial for mitochondrial homeostasis and that mitochondrial dysfunction contributes to altered barrier permeability in Stard7-deficient mice.
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Affiliation(s)
- Li Yang
- Perinatal Institute, Division of Neonatology, Perinatal and Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229-3039, USA
| | - Cheng-Lun Na
- Perinatal Institute, Division of Neonatology, Perinatal and Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229-3039, USA
| | - Shiyu Luo
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229-3039, USA
| | - David Wu
- Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229-3039, USA
| | - Simon Hogan
- Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229-3039, USA
| | - Taosheng Huang
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229-3039, USA
| | - Timothy E Weaver
- Perinatal Institute, Division of Neonatology, Perinatal and Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229-3039, USA
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12
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Reyna L, Flores-Martín J, Ridano ME, Panzetta-Dutari GM, Genti-Raimondi S. Chlorpyrifos induces endoplasmic reticulum stress in JEG-3 cells. Toxicol In Vitro 2017; 40:88-93. [DOI: 10.1016/j.tiv.2016.12.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 11/24/2016] [Accepted: 12/13/2016] [Indexed: 11/25/2022]
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13
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Flores-Martín J, Reyna L, Ridano ME, Panzetta-Dutari GM, Genti-Raimondi S. Suppression of StarD7 promotes endoplasmic reticulum stress and induces ROS production. Free Radic Biol Med 2016; 99:286-295. [PMID: 27554972 DOI: 10.1016/j.freeradbiomed.2016.08.023] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 07/29/2016] [Accepted: 08/17/2016] [Indexed: 11/19/2022]
Abstract
StarD7 is an intracellular lipid transport protein identified as up-regulated in the choriocarcinoma JEG-3 cell line. StarD7 facilitates the delivery of phosphatidylcholine (PC) to the mitochondria, and StarD7 knockdown causes a reduction in phospholipid synthesis. Since inhibition of PC synthesis may lead to endoplasmic reticulum (ER) stress we hypothesized that StarD7 may be involved in maintaining cell homeostasis. Here, we examined the effect of StarD7 silencing on ER stress response and on the levels of reactive oxygen species (ROS) in the human hepatoma cell line HepG2. StarD7 knockdown induced alterations in mitochondria and ER morphology. These changes were accompanied with an ER stress response as determined by increased expression of inositol-requiring enzyme 1α (IRE1α), calnexin, glucose regulated protein 78/immunoglobulin heavy chain-binding protein (Grp78/BiP), protein kinase-like ER kinase (PERK) as well as the phosphorylated eukaryotic translation initiation factor 2, subunit 1α (p-eIF2α). Additionally, a downregulation of the tumor suppressor p53 by a degradation mechanism was observed in StarD7 siRNA cells. Furthermore, StarD7 silencing induced ROS generation and reduced cell viability after H2O2 exposure. Decreased expression of StarD7 was associated to increased levels of the heme oxygenase-1 (HO-1) and catalase enzymes as well as in catalase enzymatic activity. Finally, no changes in levels of autophagy and apoptosis markers were observed in StarD7 siRNA treated cells respect to control cells. Taken together, these results indicate that StarD7 contributes to modulate cellular redox homeostasis.
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Affiliation(s)
- Jésica Flores-Martín
- Universidad Nacional de Córdoba-Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Químicas, Departamento de Bioquímica Clínica-Centro de Investigaciones en Bioquímica Clínica e Inmunología, Haya de la Torre y Medina Allende, X5000HUA Córdoba, Argentina
| | - Luciana Reyna
- Universidad Nacional de Córdoba-Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Químicas, Departamento de Bioquímica Clínica-Centro de Investigaciones en Bioquímica Clínica e Inmunología, Haya de la Torre y Medina Allende, X5000HUA Córdoba, Argentina
| | - Magali E Ridano
- Universidad Nacional de Córdoba-Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Químicas, Departamento de Bioquímica Clínica-Centro de Investigaciones en Bioquímica Clínica e Inmunología, Haya de la Torre y Medina Allende, X5000HUA Córdoba, Argentina
| | - Graciela M Panzetta-Dutari
- Universidad Nacional de Córdoba-Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Químicas, Departamento de Bioquímica Clínica-Centro de Investigaciones en Bioquímica Clínica e Inmunología, Haya de la Torre y Medina Allende, X5000HUA Córdoba, Argentina
| | - Susana Genti-Raimondi
- Universidad Nacional de Córdoba-Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Químicas, Departamento de Bioquímica Clínica-Centro de Investigaciones en Bioquímica Clínica e Inmunología, Haya de la Torre y Medina Allende, X5000HUA Córdoba, Argentina.
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14
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Nuebel E, Manganas P, Tokatlidis K. Orphan proteins of unknown function in the mitochondrial intermembrane space proteome: New pathways and metabolic cross-talk. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:2613-2623. [PMID: 27425144 PMCID: PMC5404111 DOI: 10.1016/j.bbamcr.2016.07.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 07/07/2016] [Accepted: 07/12/2016] [Indexed: 12/14/2022]
Abstract
The mitochondrial intermembrane space (IMS) is involved in protein transport, lipid homeostasis and metal ion exchange, while further acting in signalling pathways such as apoptosis. Regulation of these processes involves protein modifications, as well as stress-induced import or release of proteins and other signalling molecules. Even though the IMS is the smallest sub-compartment of mitochondria, its redox state seems to be tightly regulated. However, the way in which this compartment participates in the cross-talk between the multiple organelles and the cytosol is far from understood. Here we focus on newly identified IMS proteins that may represent future challenges in mitochondrial research. We present an overview of the import pathways, the recently discovered new components of the IMS proteome and how these relate to key aspects of cell signalling and progress made in stem cell and cancer research. A brief overview of the classic mitochondrial import pathways is featured Recent studies assigning a number of new proteins to the mitochondrial IMS are discussed Analysis of the expanded IMS proteomes can provide insights into organelle cross-talk and signalling pathways
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Affiliation(s)
- Esther Nuebel
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, UK
| | - Phanee Manganas
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, UK
| | - Kostas Tokatlidis
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, UK.
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15
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Yang L, Lewkowich I, Apsley K, Fritz JM, Wills-Karp M, Weaver TE. Haploinsufficiency for Stard7 is associated with enhanced allergic responses in lung and skin. THE JOURNAL OF IMMUNOLOGY 2015; 194:5635-43. [PMID: 25980009 DOI: 10.4049/jimmunol.1500231] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Accepted: 04/19/2015] [Indexed: 11/19/2022]
Abstract
Allergic asthma is a chronic inflammatory disorder that affects ∼20% of the population worldwide. Microarray analyses of nasal epithelial cells from acute asthmatic patients detected a 50% decrease in expression of Stard7, an intracellular phosphatidylcholine transport protein. To determine whether loss of Stard7 expression promotes allergic responses, mice were generated in which one allele of the Stard7 locus was globally disrupted (Stard7 (+/-) mice). OVA sensitization and challenge of Stard7(+/-) mice resulted in a significant increase in pulmonary inflammation, mucous cell metaplasia, airway hyperresponsiveness, and OVA-specific IgE compared with OVA-sensitized/challenged wild-type (WT) mice. This exacerbation was largely Th2-mediated with a significant increase in CD4(+)IL-13(+) T cells and IL-4, IL-5, and IL-13 cytokines. The loss of Stard7 was also associated with increased lung epithelial permeability and activation of proinflammatory dendritic cells in sensitized and/or challenged Stard7 (+/-) mice. Notably, OVA-pulsed dendritic cells from Stard7(+/-) mice were sufficient to confer an exaggerated allergic response in OVA-challenged WT mice, although airway hyperresponsiveness was greater in Stard7(+/-) recipients compared with WT recipients. Enhanced allergic responses in the lung were accompanied by age-dependent development of spontaneous atopic dermatitis. Overall, these data suggest that Stard7 is an important component of a novel protective pathway in tissues exposed to the extracellular environment.
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Affiliation(s)
- Li Yang
- Section of Neonatology, Perinatal and Pulmonary Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center and the University of Cincinnati College of Medicine, Cincinnati, OH 45229
| | - Ian Lewkowich
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center and the University of Cincinnati College of Medicine, Cincinnati, OH 45229; and
| | - Karen Apsley
- Section of Neonatology, Perinatal and Pulmonary Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center and the University of Cincinnati College of Medicine, Cincinnati, OH 45229
| | - Jill M Fritz
- Section of Neonatology, Perinatal and Pulmonary Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center and the University of Cincinnati College of Medicine, Cincinnati, OH 45229
| | - Marsha Wills-Karp
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205
| | - Timothy E Weaver
- Section of Neonatology, Perinatal and Pulmonary Biology, Perinatal Institute, Cincinnati Children's Hospital Medical Center and the University of Cincinnati College of Medicine, Cincinnati, OH 45229;
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16
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Chiapella G, Flores-Martín J, Ridano M, Reyna L, Magnarelli de Potas G, Panzetta-Dutari G, Genti-Raimondi S. The organophosphate chlorpyrifos disturbs redox balance and triggers antioxidant defense mechanisms in JEG-3 cells. Placenta 2013; 34:792-8. [DOI: 10.1016/j.placenta.2013.06.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2013] [Revised: 06/05/2013] [Accepted: 06/08/2013] [Indexed: 01/07/2023]
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17
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The Lipid Transfer Protein StarD7: Structure, Function, and Regulation. Int J Mol Sci 2013; 14:6170-86. [PMID: 23507753 PMCID: PMC3634439 DOI: 10.3390/ijms14036170] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Revised: 02/17/2013] [Accepted: 02/22/2013] [Indexed: 02/06/2023] Open
Abstract
The steroidogenic acute regulatory (StAR) protein-related lipid transfer (START) domain proteins constitute a family of evolutionarily conserved and widely expressed proteins that have been implicated in lipid transport, metabolism, and signaling. The 15 well-characterized mammalian START domain-containing proteins are grouped into six subfamilies. The START domain containing 7 mRNA encodes StarD7, a member of the StarD2/phosphatidylcholine transfer protein (PCTP) subfamily, which was first identified as a gene overexpressed in a choriocarcinoma cell line. Recent studies show that the StarD7 protein facilitates the delivery of phosphatidylcholine to the mitochondria. This review summarizes the latest advances in StarD7 research, focusing on the structural and biochemical features, protein-lipid interactions, and mechanisms that regulate StarD7 expression. The implications of the role of StarD7 in cell proliferation, migration, and differentiation are also discussed.
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18
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Flores-Martín J, Rena V, Márquez S, Panzetta-Dutari GM, Genti-Raimondi S. StarD7 knockdown modulates ABCG2 expression, cell migration, proliferation, and differentiation of human choriocarcinoma JEG-3 cells. PLoS One 2012; 7:e44152. [PMID: 22952907 PMCID: PMC3430668 DOI: 10.1371/journal.pone.0044152] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Accepted: 07/30/2012] [Indexed: 11/18/2022] Open
Abstract
Background StAR-related lipid transfer domain containing 7 (StarD7) is a member of the START-domain protein family whose function still remains unclear. Our data from an explorative microarray assay performed with mRNAs from StarD7 siRNA-transfected JEG-3 cells indicated that ABCG2 (ATP-binding cassette sub-family G member 2) was one of the most abundantly downregulated mRNAs. Methodology/Principal Findings Here, we have confirmed that knocking down StarD7 mRNA lead to a decrease in the xenobiotic/lipid transporter ABCG2 at both the mRNA and protein levels (−26.4% and −41%, p<0.05, at 48 h of culture, respectively). Also a concomitant reduction in phospholipid synthesis, bromodeoxyuridine (BrdU) uptake and 3H-thymidine incorporation was detected. Wound healing and transwell assays revealed that JEG-3 cell migration was significantly diminished (p<0.05). Conversely, biochemical differentiation markers such as human chorionic gonadotrophin β-subunit (βhCG) protein synthesis and secretion as well as βhCG and syncytin-1 mRNAs were increased approximately 2-fold. In addition, desmoplakin immunostaining suggested that there was a reduction of intercellular desmosomes between adjacent JEG-3 cells after knocking down StarD7. Conclusions/Significance Altogether these findings provide evidence for a role of StarD7 in cell physiology indicating that StarD7 modulates ABCG2 multidrug transporter level, cell migration, proliferation, and biochemical and morphological differentiation marker expression in a human trophoblast cell model.
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MESH Headings
- ATP Binding Cassette Transporter, Subfamily G, Member 2
- ATP-Binding Cassette Transporters/genetics
- ATP-Binding Cassette Transporters/metabolism
- Biomarkers/metabolism
- Carrier Proteins/genetics
- Carrier Proteins/metabolism
- Cell Differentiation/genetics
- Cell Line, Tumor
- Cell Movement/genetics
- Cell Proliferation
- Choriocarcinoma/genetics
- Choriocarcinoma/pathology
- Chorionic Gonadotropin, beta Subunit, Human/genetics
- Chorionic Gonadotropin, beta Subunit, Human/metabolism
- Gene Expression Regulation, Neoplastic
- Gene Knockdown Techniques
- Gene Products, env/genetics
- Gene Products, env/metabolism
- Gene Silencing
- Giant Cells/metabolism
- Humans
- Neoplasm Proteins/genetics
- Neoplasm Proteins/metabolism
- Phospholipids/biosynthesis
- Pregnancy Proteins/genetics
- Pregnancy Proteins/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Small Interfering/metabolism
- Up-Regulation/genetics
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Affiliation(s)
- Jésica Flores-Martín
- Centro de Investigaciones en Bioquímica Clínica e Inmunología-Consejo Nacional de Investigaciones Científicas y Técnicas, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Viviana Rena
- Centro de Investigaciones en Bioquímica Clínica e Inmunología-Consejo Nacional de Investigaciones Científicas y Técnicas, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Sebastián Márquez
- Centro de Investigaciones en Bioquímica Clínica e Inmunología-Consejo Nacional de Investigaciones Científicas y Técnicas, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Graciela M. Panzetta-Dutari
- Centro de Investigaciones en Bioquímica Clínica e Inmunología-Consejo Nacional de Investigaciones Científicas y Técnicas, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Susana Genti-Raimondi
- Centro de Investigaciones en Bioquímica Clínica e Inmunología-Consejo Nacional de Investigaciones Científicas y Técnicas, Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- * E-mail:
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Ikeda Y, Tanji E, Makino N, Kawata S, Furukawa T. MicroRNAs associated with mitogen-activated protein kinase in human pancreatic cancer. Mol Cancer Res 2011; 10:259-69. [PMID: 22188669 DOI: 10.1158/1541-7786.mcr-11-0035] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Aberrant expression of microRNAs (miRNA) is associated with phenotypes of various cancers, including pancreatic cancer. However, the mechanism of the aberrant expression is largely unknown. Activation of the mitogen-activated protein kinase (MAPK) signaling pathway plays a crucial role in gene expression related to the malignant phenotype of pancreatic cancer. Hence, we studied the role of MAPK in the aberrant expression of miRNAs in pancreatic cancer cells. The alterations in expression of 183 miRNAs induced by activation or inactivation of MAPK were assayed in cultured pancreatic cancer cells and HEK293 cells by means of the quantitative real-time PCR method. We found that four miRNAs, namely, miR-7-3, miR-34a, miR-181d, and miR-193b, were preferentially associated with MAPK activity. Among these miRNAs, miR-7-3 was upregulated by active MAPK, whereas the others were downregulated. Promoter assays indicated that the promoter activities of the host genes of miR-7-3 and miR-34a were both downregulated by alteration in MAPK activity. Exogenous overexpression of the MAPK-associated miRNAs had the effect of inhibition of the proliferation of cultured pancreatic cancer cells; miR-193b was found to exhibit the most remarkable inhibition. A search for target genes of miR-193b led to identification of CCND1, NT5E, PLAU, STARD7, STMN1, and YWHAZ as the targets. Translational suppression of these genes by miR-193b was confirmed by reporter assay. These results indicate that activation of MAPK may play a significant role in aberrant expression of miRNAs and their associated phenotypes in pancreatic cancer.
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Affiliation(s)
- Yushi Ikeda
- International Research and Educational Institute for Integrated Medical Sciences, Tokyo Women's Medical University, Tokyo, Japan
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Rena V, Flores-Martín J, Angeletti S, Panzetta-Dutari GM, Genti-Raimondi S. StarD7 gene expression in trophoblast cells: contribution of SF-1 and Wnt-beta-catenin signaling. Mol Endocrinol 2011; 25:1364-75. [PMID: 21622533 DOI: 10.1210/me.2010-0503] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Steroidogenic acute regulatory protein-related lipid transfer domain containing 7 (StarD7) is a poorly characterized member of the steroidogenic acute regulatory protein-related lipid transfer proteins, up-regulated in JEG-3 cells, involved in intracellular transport and metabolism of lipids. Previous studies dealing with the mechanisms underlying the human StarD7 gene expression led us to define the cis-acting regulatory sequences in the StarD7 promoter using as a model JEG-3 cells. These include a functional T cell-specific transcription factor 4 (TCF4) site involved in Wnt-β-catenin signaling. To understand these mechanisms in more depth, we examined the steroidogenic factor 1 (SF-1) contribution to StarD7 expression. Cotransfection experiments in JEG-3 cells point out that the StarD7 promoter is activated by SF-1, and this effect is increased by forskolin. EMSA using JEG-3 nuclear proteins demonstrated that SF-1 binds to the StarD7 promoter. Additionally, chromatin immunoprecipitation analysis indicated that SF-1 and β-catenin are bound in vivo to the StarD7 promoter. Reporter gene assays in combination with mutations in the SF-1 and TCF4 binding sites revealed that the StarD7 promoter is synergistically activated by SF-1 and β-catenin and that the TCF4 binding site (-614/-608) plays an important role in this activation. SF-1 amino acid mutations involved in the physical interaction with β-catenin abolished this activation; thus demonstrating that the contact between the two proteins is necessary for an efficient StarD7 transcriptional induction. Finally, these data suggest that β-catenin could function as a bridge between SF-1 and TCF4 forming a ternary complex, which would stimulate StarD7 expression. The SF-1 and β-catenin pathway convergence on StarD7 expression may have important implications in the phospholipid uptake and transport, contributing to the normal trophoblast development.
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Affiliation(s)
- Viviana Rena
- Universidad Nacional de Córdoba-Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Químicas, Departamento de Bioquímica Clínica-Centro de Investigaciones en Bioquímica Clínica e Inmunología, X5000HUA Córdoba, Argentina
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Horibata Y, Sugimoto H. StarD7 mediates the intracellular trafficking of phosphatidylcholine to mitochondria. J Biol Chem 2009; 285:7358-65. [PMID: 20042613 DOI: 10.1074/jbc.m109.056960] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Steroidogenic acute regulatory protein-related lipid transfer (START) domains, found in 15 mammalian proteins termed StarD1-StarD15, are lipid-binding domains implicated in the intracellular lipid transport systems. In the present study, we analyzed the lipid ligand and function of StarD7. We found two variable forms of mammalian StarD7, termed StarD7-I and StarD7-II. Unlike StarD7-II, StarD7-I contained a mitochondrial-targeting sequence in its N terminus. Overexpressed StarD7-I tagged with V5/His in HEPA-1 cells was mainly observed in the mitochondria of cells prepared at low cellular density, but it was distributed in the cytoplasm of high density cells. StarD7-II was constantly distributed in the cytoplasm at any cellular density. Endogenous StarD7 in HEPA-1 cells and rat liver was also distributed in both the cytoplasm and the mitochondria. A protease K protection assay indicated that the mitochondrial StarD7 was associated with the outer mitochondrial membrane. The purified recombinant StarD7 specifically catalyzed the transfer of PC between lipid vesicles in vitro. Furthermore, the intracellular transport of fluorescent PC that was exogenously incorporated into the mitochondria was increased in cells that overexpressed StarD7-I. These results suggest that StarD7 facilitates the delivery of PC to mitochondria in non-vesicular system.
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Affiliation(s)
- Yasuhiro Horibata
- Department of Biochemistry, Dokkyo Medical University School of Medicine, 880 Kitakobayashi, Mibu, Tochigi 321-0293, Japan
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Rena V, Angeletti S, Panzetta-Dutari G, Genti-Raimondi S. Activation of beta-catenin signalling increases StarD7 gene expression in JEG-3 cells. Placenta 2009; 30:876-83. [PMID: 19679347 DOI: 10.1016/j.placenta.2009.07.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2009] [Revised: 07/23/2009] [Accepted: 07/26/2009] [Indexed: 10/20/2022]
Abstract
StarD7 gene encodes a protein that belongs to the StAR-related lipid transfer proteins involved in intracellular transport and metabolism of lipids. It has been previously documented that StarD7 has a wide-spread mRNA expression in trophoblastic tissues and several tumour cell lines with highest levels in both choriocarcinoma JEG-3 and JAR cells, hepatocellular carcinoma HepG2, and colorectal adenocarcinoma HT-29 cells. To understand the molecular mechanisms that regulate the expression of the human StarD7 gene, we have cloned and characterized the 5'-flanking region of the gene. Transient transfections of several 5'deleted StarD7-promoter-firefly luciferase constructs into JEG-3 cells indicated that the -312/+157 region contains the gene minimal promoter. In addition, sequence analysis of a 1.6kb gene fragment revealed the presence of a TATA-less promoter as well as multiple regulatory motifs, including one regulatory element corresponding to the T-cell factor 4 (TCF4) binding site. Inhibition of glycogen synthase kinase-3beta (GSK3beta), a component of Wnt/beta-catenin signalling, increased both StarD7 mRNA and protein expression as well as its promoter activity. Co-transfection experiments in JEG-3 cell line revealed that the StarD7 promoter is activated by TCF4 transcription factor and by its beta-catenin coactivator. Moreover, site-directed mutagenesis of the TCF4 site located -614/-608bp relative to the transcription start site markedly diminished StarD7 promoter activity. Chromatin immunoprecipitation analysis demonstrated that beta-catenin and TCF4 are bound in vivo to the StarD7 gene promoter in JEG-3 cells treated with lithium chloride. Collectively, these studies show that beta-catenin and TCF4 activate the human StarD7 gene interacting with its promoter region through Wnt/beta-catenin signalling.
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Affiliation(s)
- V Rena
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Córdoba, Argentina
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Angeletti S, Rena V, Nores R, Fretes R, Panzetta-Dutari G, Genti-Raimondi S. Expression and Localization of StarD7 in Trophoblast Cells. Placenta 2008; 29:396-404. [DOI: 10.1016/j.placenta.2008.02.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Revised: 02/18/2008] [Accepted: 02/21/2008] [Indexed: 01/16/2023]
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Alpy F, Tomasetto C. Give lipids a START: the StAR-related lipid transfer (START) domain in mammals. J Cell Sci 2005; 118:2791-801. [PMID: 15976441 DOI: 10.1242/jcs.02485] [Citation(s) in RCA: 291] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The steroidogenic acute regulatory protein (StAR)-related lipid transfer (START) domain is a protein module of approximately 210 residues that binds lipids, including sterols. Fifteen mammalian proteins, STARD1-STARD15, possess a START domain and these can be grouped into six subfamilies. Cholesterol, 25-hydroxycholesterol, phosphatidylcholine, phosphatidylethanolamine and ceramides are ligands for STARD1/STARD3/STARD5, STARD5, STARD2/STARD10, STARD10 and STARD11, respectively. The lipids or sterols bound by the remaining 9 START proteins are unknown. Recent studies show that the C-terminal end of the domain plays a fundamental role, forming a lid over a deep lipid-binding pocket that shields the ligand from the external environment. The START domain can be regarded as a lipid-exchange and/or a lipid-sensing domain. Mammalian START proteins have diverse expression patterns and can be found free in the cytoplasm, attached to membranes or in the nucleus. They appear to function in a variety of distinct physiological processes, such as lipid transfer between intracellular compartments, lipid metabolism and modulation of signaling events. Mutation or misexpression of START proteins is linked to pathological processes, including genetic disorders, autoimmune disease and cancer.
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Affiliation(s)
- Fabien Alpy
- Inserm, U682 Strasbourg, F67200, Development and Physiopathology of the Intestine and Pancreas, University Louis Pasteur, Strasbourg, France
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Sun Y, Lu X, Yin L, Zhao F, Feng Y. Inhibition of DLX4 promotes apoptosis in choriocarcinoma cell lines. Placenta 2005; 27:375-83. [PMID: 15975650 DOI: 10.1016/j.placenta.2005.03.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2004] [Revised: 03/15/2005] [Accepted: 03/17/2005] [Indexed: 02/06/2023]
Abstract
Homeodomain (HDM) proteins encoded by homeobox (HBX) genes represent a large family of transcriptional factors that control differentiation and development in certain cell types. DLX4 is a member of Distal-less (DLX) family of HBX genes. Recent studies have demonstrated that abnormal expression of DLX4 is present in several types of human tumors, such as breast cancer, leukemia and colon cancer. In the present study, we investigated DLX4 mRNA and protein expression in both normal placental tissues and human choriocarcinoma cell lines. Also, using RNA interference (RNAi) technique, we knocked down the expression of DLX4 and examined apoptosis in JEG-3 cells. Our studies demonstrated that DLX4 RNAi inhibited DLX4 mRNA expression and decreased DLX4 protein mass specifically and effectively, potentially enhancing apoptosis. Moreover, we examined expression of caspase-3 and caspase-8, and found that both caspases were increased after DLX4 knockdown. However, DLX4 RNAi did not influence Bax expression in JEG-3 cells. In conclusion, this study suggests that DLX4 may be involved in the survival of human choriocarcinoma cells, which may be mediated by the inhibition of apoptosis. The detailed mechanism needs further investigation.
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Affiliation(s)
- Y Sun
- Hospital of Obstetrics & Gynecology, Fudan University, 419 Fangxie Road, Shanghai 200011, China
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Angeletti S, Maggio B, Genti-Raimondi S. Surface activity and interaction of StarD7 with phospholipid monolayers. Biochem Biophys Res Commun 2004; 314:181-5. [PMID: 14715263 DOI: 10.1016/j.bbrc.2003.12.076] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
StarD7 protein forms stable Gibbs and Langmuir monolayers at the air-buffer interface showing marked surface activity. The latter is enhanced by penetration into phospholipid films at an initial surface pressure above the protein's own equilibrium adsorption surface pressure to a lipid-free interface. The protein-phospholipid stabilizing interactions at the interface depend on the lipid, with preference for phosphatidylserine, cholesterol, and phosphatidylglycerol, and the increases of lateral surface pressure generated are comparable to those of other membrane-active proteins. The surface activity of StarD7 is strong enough to thermodynamically drive and retain StarD7 at the lipid membrane interface where it may undergo lipid-dependent reorganization as indicated by changes of surface pressure and electrostatics.
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Affiliation(s)
- Sofia Angeletti
- Dpto. de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Ciudad Universitaria, Córdoba, Argentina
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