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Shah PW, Reinberger T, Hashmi S, Aherrahrou Z, Erdmann J. MRAS in coronary artery disease-Unchartered territory. IUBMB Life 2024; 76:300-312. [PMID: 38251784 DOI: 10.1002/iub.2805] [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: 07/04/2023] [Accepted: 12/03/2023] [Indexed: 01/23/2024]
Abstract
Genome-wide association studies (GWAS) have identified coronary artery disease (CAD) susceptibility locus on chromosome 3q22.3. This locus contains a cluster of several genes that includes muscle rat sarcoma virus (MRAS). Common MRAS variants are also associated with CAD causing risk factors such as hypertension, dyslipidemia, obesity, and type II diabetes. The MRAS gene is an oncogene that encodes a membrane-bound small GTPase. It is involved in a variety of signaling pathways, regulating cell differentiation and cell survival (mitogen-activated protein kinase [MAPK]/extracellular signal-regulated kinase and phosphatidylinositol 3-kinase) as well as acute phase response signaling (tumor necrosis factor [TNF] and interleukin 6 [IL6] signaling). In this review, we will summarize the role of genetic MRAS variants in the etiology of CAD and its comorbidities with the focus on tissue distribution of MRAS isoforms, cell type/tissue specificity, and mode of action of single nucleotide variants in MRAS associated complex traits. Finally, we postulate that CAD risk variants in the MRAS locus are specific to smooth muscle cells and lead to higher levels of MRAS, particularly in arterial and cardiac tissue, resulting in MAPK-dependent tissue hypertrophy or hyperplasia.
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Affiliation(s)
- Pashmina Wiqar Shah
- Institute for Cardiogenetics, University of Lübeck, Lübeck, Germany
- DZHK (German Research Centre for Cardiovascular Research), Lübeck, Germany
- University Heart Center Lübeck, Lübeck, Germany
| | - Tobias Reinberger
- Institute for Cardiogenetics, University of Lübeck, Lübeck, Germany
- DZHK (German Research Centre for Cardiovascular Research), Lübeck, Germany
- University Heart Center Lübeck, Lübeck, Germany
| | - Satwat Hashmi
- Department of Biological and Biomedical Sciences, Aga Khan University, Karachi, Pakistan
| | - Zouhair Aherrahrou
- Institute for Cardiogenetics, University of Lübeck, Lübeck, Germany
- DZHK (German Research Centre for Cardiovascular Research), Lübeck, Germany
- University Heart Center Lübeck, Lübeck, Germany
| | - Jeanette Erdmann
- Institute for Cardiogenetics, University of Lübeck, Lübeck, Germany
- DZHK (German Research Centre for Cardiovascular Research), Lübeck, Germany
- University Heart Center Lübeck, Lübeck, Germany
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2
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Quirion L, Robert A, Boulais J, Huang S, Bernal Astrain G, Strakhova R, Jo CH, Kherdjemil Y, Thibault MP, Faubert D, Kmita M, Baskin JM, Gingras AC, Smith MJ, Cote JF. Mapping the global interactome of the ARF family reveals spatial organization in cellular signaling pathways. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.03.01.530598. [PMID: 36909472 PMCID: PMC10002736 DOI: 10.1101/2023.03.01.530598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
Abstract
The ADP-ribosylation factors (ARFs) and ARF-like (ARLs) GTPases serve as essential molecular switches governing a wide array of cellular processes. In this study, we utilized proximity-dependent biotin identification (BioID) to comprehensively map the interactome of 28 out of 29 ARF and ARL proteins in two cellular models. Through this approach, we identified ~3000 high-confidence proximal interactors, enabling us to assign subcellular localizations to the family members. Notably, we uncovered previously undefined localizations for ARL4D and ARL10. Clustering analyses further exposed the distinctiveness of the interactors identified with these two GTPases. We also reveal that the expression of the understudied member ARL14 is confined to the stomach and intestines. We identified phospholipase D1 (PLD1) and the ESCPE-1 complex, more precisely SNX1, as proximity interactors. Functional assays demonstrated that ARL14 can activate PLD1 in cellulo and is involved in cargo trafficking via the ESCPE-1 complex. Overall, the BioID data generated in this study provide a valuable resource for dissecting the complexities of ARF and ARL spatial organization and signaling.
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Inflammation-Related Risk Loci in Genome-Wide Association Studies of Coronary Artery Disease. Cells 2021; 10:cells10020440. [PMID: 33669721 PMCID: PMC7921935 DOI: 10.3390/cells10020440] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 02/02/2021] [Accepted: 02/17/2021] [Indexed: 12/13/2022] Open
Abstract
Although the importance of inflammation in atherosclerosis is now well established, the exact molecular processes linking inflammation to the development and course of the disease are not sufficiently understood. In this context, modern genetics—as applied by genome-wide association studies (GWAS)—can serve as a comprehensive and unbiased tool for the screening of potentially involved pathways. Indeed, a considerable proportion of loci discovered by GWAS is assumed to affect inflammatory processes. Despite many well-replicated association findings, however, translating genomic hits to specific molecular mechanisms remains challenging. This review provides an overview of the currently most relevant inflammation-related GWAS findings in coronary artery disease and explores their potential clinical perspectives.
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Endo T. M-Ras is Muscle-Ras, Moderate-Ras, Mineral-Ras, Migration-Ras, and Many More-Ras. Exp Cell Res 2020; 397:112342. [PMID: 33130177 DOI: 10.1016/j.yexcr.2020.112342] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 10/23/2020] [Indexed: 11/19/2022]
Abstract
The Ras family of small GTPases comprises about 36 members in humans. M-Ras is related to classical Ras with regard to its regulators and effectors, but solely constitutes a subfamily among the Ras family members. Although classical Ras strongly binds Raf and highly activates the ERK pathway, M-Ras less strongly binds Raf and moderately but sustainedly activates the ERK pathway to induce neuronal differentiation. M-Ras also possesses specific effectors, including RapGEFs and the PP1 complex Shoc2-PP1c, which dephosphorylates Raf to activate the ERK pathway. M-Ras is highly expressed in the brain and plays essential roles in dendrite formation during neurogenesis, in contrast to the axon formation by R-Ras. M-Ras is also highly expressed in the bone and induces osteoblastic differentiation and transdifferentiation accompanied by calcification. Moreover, M-Ras elicits epithelial-mesenchymal transition-mediated collective and single cell migration through the PP1 complex-mediated ERK pathway activation. Activating missense mutations in the MRAS gene have been detected in Noonan syndrome, one of the RASopathies, and MRAS gene amplification occurs in several cancers. Furthermore, several SNPs in the MRAS gene are associated with coronary artery disease, obesity, and dyslipidemia. Therefore, M-Ras carries out a variety of cellular, physiological, and pathological functions. Further investigations may reveal more functions of M-Ras.
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Affiliation(s)
- Takeshi Endo
- Department of Biology, Graduate School of Science, Chiba University, 1-33 Yayoicho, Inageku, Chiba, Chiba 263-8522, Japan.
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5
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Ishihara S, Sato T, Du G, Guardavaccaro D, Nakajima A, Sawai S, Kataoka T, Katagiri K. Phosphatidic acid-dependent localization and basal de-phosphorylation of RA-GEFs regulate lymphocyte trafficking. BMC Biol 2020; 18:75. [PMID: 32600317 PMCID: PMC7325102 DOI: 10.1186/s12915-020-00809-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 06/15/2020] [Indexed: 01/03/2023] Open
Abstract
Background Lymphocytes circulate between peripheral lymphoid tissues via blood and lymphatic systems, and chemokine-induced migration is important in trafficking lymphocytes to distant sites. The small GTPase Rap1 is important in mediating lymphocyte motility, and Rap1-GEFs are involved in chemokine-mediated Rap1 activation. Here, we describe the roles and mechanisms of Rap1-GEFs in lymphocyte trafficking. Results In this study, we show that RA-GEF-1 and 2 (also known as Rapgef2 and 6) are key guanine nucleotide exchange factors (GEF) for Rap1 in lymphocyte trafficking. Mice harboring T cell-specific knockouts of Rapgef2/6 demonstrate defective homing and egress of T cells. Sphingosine-1-phosphate (S1P) as well as chemokines activates Rap1 in a RA-GEF-1/2-dependent manner, and their deficiency in T cells impairs Mst1 phosphorylation, cell polarization, and chemotaxis toward S1P gradient. On the other hand, B cell-specific knockouts of Rapgef2/6 impair chemokine-dependent retention of B cells in the bone marrow and passively facilitate egress. Phospholipase D2-dependent production of phosphatidic acid by these chemotactic factors determines spatial distribution of Rap1-GTP subsequent to membrane localization of RA-GEFs and induces the development of front membrane. On the other hand, basal de-phosphorylation of RA-GEFs is necessary for chemotactic factor-dependent increase in GEF activity for Rap1. Conclusions We demonstrate here that subcellular distribution and activation of RA-GEFs are key factors for a directional movement of lymphocytes and that phosphatidic acid is critical for membrane translocation of RA-GEFs with chemokine stimulation.
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Affiliation(s)
- Sayaka Ishihara
- Department of Biosciences, School of Science, Kitasato University, 1-15-1 Kitasato, Minamiku, Sagamihara, Kanagawa, 252-0344, Japan
| | - Tsuyoshi Sato
- Department of Biosciences, School of Science, Kitasato University, 1-15-1 Kitasato, Minamiku, Sagamihara, Kanagawa, 252-0344, Japan
| | - Guangwei Du
- Department of Integrative Biology & Pharmacology, University of Texas Health Science at Houston, 6431 Fannin St, Houston, TX, 77030, USA
| | - Daniele Guardavaccaro
- Hubrecht Institute-KNAW and University Medical Center Utrecht, Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - Akihiko Nakajima
- Department of Basic Science, Graduate School of Arts and Sciences, University of Tokyo, Tokyo, 153-8902, Japan
| | - Satoshi Sawai
- Department of Basic Science, Graduate School of Arts and Sciences, University of Tokyo, Tokyo, 153-8902, Japan
| | - Tohru Kataoka
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan
| | - Koko Katagiri
- Department of Biosciences, School of Science, Kitasato University, 1-15-1 Kitasato, Minamiku, Sagamihara, Kanagawa, 252-0344, Japan.
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Momoi Y, Nishikimi A, Du G, Kataoka T, Katagiri K. Phosphatidic acid regulates subcellular distribution of RA-GEFs critical for chemokine-dependent migration. Biochem Biophys Res Commun 2020; 524:325-331. [PMID: 31996307 DOI: 10.1016/j.bbrc.2020.01.080] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2019] [Accepted: 01/15/2020] [Indexed: 01/05/2023]
Abstract
Integrin activation by Rap1-GTP is pivotal for lymphocyte trafficking. In this study, we show the phosphatidic acid (PA)-dependent membrane distribution of RA-GEF-1 and -2 (also known as Rapgef2 and 6), which are guanine nucleotide exchange factors for Rap1, plays important roles in lymphocyte migration. RA-GEF-1 associates with PA through 919-967 aa within CDC25 homology domain, and the deletion of this region of RA-GEF-1 inhibits chemokine-dependent migration. Chemokine stimulation induces temporal production of PA on the plasma membrane, which is not necessary for Rap1 activation, but the translocation of RA-GEFs. Thus, chemokine-dependent generation of PA is critical for lymphocyte migration through membrane localization of RA-GEFs.
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Affiliation(s)
- Yasuyuki Momoi
- Department of Biosciences, School of Science, Kitasato University, 1-15-1 Kitasato, Minamiku, Sagamihara, Kanagawa, 252-0337, Japan
| | - Akihiko Nishikimi
- Department of Biosciences, School of Science, Kitasato University, 1-15-1 Kitasato, Minamiku, Sagamihara, Kanagawa, 252-0337, Japan
| | - Guangwei Du
- Department of Integrative Biology & Pharmacology, University of Texas Health Science at Houston 6431 Fannin St, Houston, TX, 77030, USA
| | - Tohru Kataoka
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan
| | - Koko Katagiri
- Department of Biosciences, School of Science, Kitasato University, 1-15-1 Kitasato, Minamiku, Sagamihara, Kanagawa, 252-0337, Japan.
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Song Y, Ma R, Zhang H. The influence of MRAS gene variants on ischemic stroke and serum lipid levels in Chinese Han population. Medicine (Baltimore) 2019; 98:e18065. [PMID: 31770223 PMCID: PMC6890362 DOI: 10.1097/md.0000000000018065] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Previous studies have indicated that muscle RAS oncogene homolog (MRAS) gene played an important role in cardiovascular diseases. However, the effect of MRAS genetic variations on ischemic stroke (IS) is still not clear. The aim of the current study was to investigate the association between the MRAS polymorphism and IS risk in Han populations.Three SNPs (rs40593, rs751357, rs6782181) at MRAS were selected for genotyping in a sample of 240 IS patients and 430 controls. Logistic regression was performed to evaluate the association of 3 SNPs with IS and IS subgroups.No association of MRAS SNPs with IS risk was observed, while G allele of rs40593 was associated with increased risk of cerebral infarction area. Compared with carriers of the AA genotype, the risk of carriers of the AG+GG genotype increased, with an OR (95%CI) of 2.337 (1.175-4.647), P = .016. In relation to lipid profile, rs40593, rs751357, rs6782181 were associated with increased total cholesterol (TC) levels.Summarily, this study suggested that MRAS rs40593 may contribute to the increased risk of area of cerebral infarction of IS in Han population. rs40593, rs751357, and rs6782181 were associated with higher serum TC levels.
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Affiliation(s)
| | - Rui Ma
- Department of Hemodialysis, Jieshou City People's Hospital, Fuyang, China
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Hadji Rasouliha S, Barrientos L, Anderegg L, Klesty C, Lorenz J, Chevallier L, Jagannathan V, Rösch S, Leeb T. A RAPGEF6 variant constitutes a major risk factor for laryngeal paralysis in dogs. PLoS Genet 2019; 15:e1008416. [PMID: 31647804 PMCID: PMC6812752 DOI: 10.1371/journal.pgen.1008416] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 09/11/2019] [Indexed: 12/17/2022] Open
Abstract
Laryngeal paralysis (LP) is the inability to abduct the arytenoid cartilages during inspiration, resulting in a partial to complete airway obstruction and consequent respiratory distress. Different forms of LP with varying age of onset exist in dogs. Hereditary early onset forms were reported in several dog breeds. In most breeds, hereditary LP is associated with other neurologic pathologies. Using a genome-wide association study and haplotype analyses, we mapped a major genetic risk factor for an early onset LP in Miniature Bull Terriers to a ~1.3 Mb interval on chromosome 11. Whole genome sequencing of an affected Miniature Bull Terrier and comparison to 598 control genomes revealed a 36 bp insertion into exon 15 of the RAPGEF6 gene (c.1793_1794ins36). The imperfect genotype-phenotype correlation suggested a complex mode of inheritance with a major genetic risk factor involving a recessive risk allele. Homozygosity for the insertion was associated with a 10- to 17-fold increased risk for LP. The insertion allele was only found in Miniature Bull Terriers and Bull Terriers. It was absent from >1000 control dogs of other dog breeds. The insertion sequence contains a splice acceptor motif leading to aberrant splicing in transcripts originating from the mutant allele (r.1732_1780del). This leads to a frameshift and a premature stop codon, p.(Ile587ProfsTer5), removing 64% of the open reading frame. Our results suggest an important role of RAPGEF6 in laryngeal nerve function and provide new clues to its physiological significance. Laryngeal paralysis (LP) leads to respiratory distress in affected dogs and can be fatal in severe cases. Many different forms of LP with different etiologies exist. Striking breed predispositions suggest that genetic factors contribute to some forms of LP. During the last years, dog breeders noticed an increased prevalence of an early onset LP in Miniature Bull Terriers. We mapped a major risk locus for this specific form of LP to a ~1.3 Mb interval on dog chromosome 11. Whole genome sequence analysis of an affected dog and comparison to 598 control genomes revealed a single protein-changing genetic variant in the critical interval. This variant, a 36 bp insertion into a coding exon of the RAPGEF6 gene, creates a cryptic splice site and leads to the expression of an aberrantly spliced transcript with a premature stop codon. This suggests that the insertion results in a loss-of-function allele. Dogs that are homozygous for the insertion have a 10- to 17-fold increased risk to develop LP. The genotype-phenotype association is not perfect, suggesting that other genetic and/or environmental factors also contribute to the development of LP. Our results suggest an important role of RAPGEF6 in laryngeal nerve function.
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Affiliation(s)
| | - Laura Barrientos
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- Instituto de Genética Veterinaria (IGEVET), CCT La Plata—CONICET—Facultad de Ciencias Veterinarias, Universidad Nacional de La Plata (UNLP), La Plata, Buenos Aires, Argentina
| | - Linda Anderegg
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | | | | | - Lucie Chevallier
- U955 –IMRB, Team 10—Biology of the neuromuscular system, Inserm, UPEC, Ecole nationale vétérinaire d’Alfort, Maisons-Alfort, France
| | - Vidhya Jagannathan
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Sarah Rösch
- Small Animal Department, ENT-Unit, University of Leipzig, Leipzig, Germany
| | - Tosso Leeb
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- * E-mail:
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9
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Hanlon K, Thompson A, Pantano L, Hutchinson JN, Al-Obeidi A, Wang S, Bliss-Moreau M, Helble J, Alexe G, Stegmaier K, Bauer DE, Croker BA. Single-cell cloning of human T-cell lines reveals clonal variation in cell death responses to chemotherapeutics. Cancer Genet 2019; 237:69-77. [PMID: 31447068 DOI: 10.1016/j.cancergen.2019.06.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 04/18/2019] [Accepted: 06/09/2019] [Indexed: 12/12/2022]
Abstract
Genetic modification of human leukemic cell lines using CRISPR-Cas9 has become a staple of gene-function studies. Single-cell cloning of modified cells is frequently used to facilitate studies of gene function. Inherent in this approach is an assumption that the genetic drift, amplified in some cell lines by mutations in DNA replication and repair machinery, as well as non-genetic factors will not introduce significant levels of experimental cellular heterogeneity in clones derived from parental populations. In this study, we characterize the variation in cell death of fifty clonal cell lines generated from human Jurkat and MOLT-4 T-cells edited by CRISPR-Cas9. We demonstrate a wide distribution of sensitivity to chemotherapeutics between non-edited clonal human leukemia T-cell lines, and also following CRISPR-Cas9 editing at the NLRP1 locus, or following transfection with non-targeting sgRNA controls. The cell death sensitivity profile of clonal cell lines was consistent across experiments and failed to revert to the non-clonal parental phenotype. Whole genome sequencing of two clonal cell lines edited by CRISPR-Cas9 revealed unique and shared genetic variants, which had minimal read support in the non-clonal parental population and were not suspected CRISPR-Cas9 off-target effects. These variants included genes related to cell death and drug metabolism. The variation in cell death phenotype of clonal populations of human T-cell lines may be a consequence of T-cell line genetic instability, and to a lesser extent clonal heterogeneity in the parental population or CRISPR-Cas9 off-target effects not predicted by current models. This work highlights the importance of genetic variation between clonal T-cell lines in the design, conduct, and analysis of experiments to investigate gene function after single-cell cloning.
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Affiliation(s)
- Kathleen Hanlon
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, United States
| | - Alex Thompson
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, United States
| | - Lorena Pantano
- Department of Biostatistics, Harvard Chan School of Public Health, Boston, MA, United States
| | - John N Hutchinson
- Department of Biostatistics, Harvard Chan School of Public Health, Boston, MA, United States
| | - Arshed Al-Obeidi
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, United States
| | - Shu Wang
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, United States
| | - Meghan Bliss-Moreau
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, United States
| | - Jennifer Helble
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA, United States
| | - Gabriela Alexe
- Department of Pediatric Oncology, Dana-Farber Cancer Institute and Boston Children's Hospital, Boston, MA, United States
| | - Kimberly Stegmaier
- Department of Pediatric Oncology, Dana-Farber Cancer Institute and Boston Children's Hospital, Boston, MA, United States
| | - Daniel E Bauer
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, United States; Department of Pediatrics, Harvard Medical School, Boston, MA, United States
| | - Ben A Croker
- Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, United States; Department of Pediatrics, Harvard Medical School, Boston, MA, United States.
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10
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Abstract
Painful temporomandibular disorders (TMDs) are the leading cause of chronic orofacial pain, but its underlying molecular mechanisms remain obscure. Although many environmental factors have been associated with higher risk of developing painful TMD, family and twin studies support a heritable genetic component as well. We performed a genome-wide association study assuming an additive genetic model of TMD in a discovery cohort of 999 cases and 2031 TMD-free controls from the Orofacial Pain: Prospective Evaluation and Risk Assessment (OPPERA) study. Using logistic models adjusted for sex, age, enrollment site, and race, we identified 3 distinct loci that were significant in combined or sex-segregated analyses. A single-nucleotide polymorphism on chromosome 3 (rs13078961) was significantly associated with TMD in males only (odds ratio = 2.9, 95% confidence interval: 2.02-4.27, P = 2.2 × 10). This association was nominally replicated in a meta-analysis of 7 independent orofacial pain cohorts including 160,194 participants (odds ratio = 1.16, 95% confidence interval: 1.0-1.35, P = 2.3 × 10). Functional analysis in human dorsal root ganglia and blood indicated this variant is an expression quantitative trait locus, with the minor allele associated with decreased expression of the nearby muscle RAS oncogene homolog (MRAS) gene (beta = -0.51, P = 2.43 × 10). Male mice, but not female mice, with a null mutation of Mras displayed persistent mechanical allodynia in a model of inflammatory pain. Genetic and behavioral evidence support a novel mechanism by which genetically determined MRAS expression moderates the resiliency to chronic pain. This effect is male-specific and may contribute to the lower rates of painful TMD in men.
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11
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Li R, Bai S, Yang D, Dong C. A crayfish Ras gene is involved in the defense against bacterial infection under high temperature. FISH & SHELLFISH IMMUNOLOGY 2019; 86:608-617. [PMID: 30502469 DOI: 10.1016/j.fsi.2018.11.062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 11/03/2018] [Accepted: 11/27/2018] [Indexed: 06/09/2023]
Abstract
Temperature is an important environmental factor influencing crustacean resistance to pathogen infection. However, the mechanism underlying immune regulation by temperature remains unclear in crustacean. Here, we report a Ras gene of crayfish (designated as PcRAS1) which is involved in immune regulation of crayfish under high temperature. PcRAS1 is induced by both high temperature and bacterial infection and the induction by bacterial infection is associated with temperature. Significant changes of PcRAS1 expression was observed at 32 °C and 24 °C after infection with Aeromonas hydrophila, but relative moderate alternation was found at 16 °C after challenged with A. hydrophila. PcRAS1 silencing significantly reduced crayfish survival from high temperature (32 °C and 24 °C) or bacterial infection at 32 °C, but there was no significant effect on survival from bacterial infection at 24 °C or 16 °C. Further analysis reveals that PO activity is reduced by high temperature or enhanced by bacterial infection. Moreover, both the decreased PO activity and the enhanced PO activity are affected by PcRAS1 expression. PcRAS1 silencing further reduces PO activity under high temperature and compromises the enhanced PO activity by bacterial infection. Lipid peroxidation (LPO) and total antioxidant capacity (TAC) are also involved in the responses to high temperature. LPO is enhanced by lower temperature. TAC is reduced by high temperature and TAC change resulting from high temperature is amplified by PcRAS1 silencing. These results collectively indicate that PcRAS1 is involved in immune regulation against bacterial infection mediated by temperature.
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Affiliation(s)
- Ronghui Li
- College of Life Science, Qingdao Agricultural University, Qingdao, 266109, China
| | - Suhua Bai
- College of Life Science, Qingdao Agricultural University, Qingdao, 266109, China
| | - Decui Yang
- College of Life Science, Qingdao Agricultural University, Qingdao, 266109, China
| | - Chaohua Dong
- College of Life Science, Qingdao Agricultural University, Qingdao, 266109, China.
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12
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Young LC, Rodriguez-Viciana P. MRAS: A Close but Understudied Member of the RAS Family. Cold Spring Harb Perspect Med 2018; 8:cshperspect.a033621. [PMID: 29311130 DOI: 10.1101/cshperspect.a033621] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
MRAS is the closest relative to the classical RAS oncoproteins and shares most regulatory and effector interactions. However, it also has unique functions, including its ability to function as a phosphatase regulatory subunit when in complex with SHOC2 and protein phosphatase 1 (PP1). This phosphatase complex regulates a crucial step in the activation cycle of RAF kinases and provides a key coordinate input required for efficient ERK pathway activation and transformation by RAS. MRAS mutations rarely occur in cancer but deregulated expression may play a role in tumorigenesis in some settings. Activating mutations in MRAS (as well as SHOC2 and PP1) do occur in the RASopathy Noonan syndrome, underscoring a key role for MRAS within the RAS-ERK pathway. MRAS also has unique roles in cell migration and differentiation and has properties consistent with a key role in the regulation of cell polarity. Further investigations should shed light on what remains a relatively understudied RAS family member.
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Affiliation(s)
- Lucy C Young
- UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, California 94158
| | - Pablo Rodriguez-Viciana
- UCL Cancer Institute, Paul O'Gorman Building, University College London, London WC1E 6BT, United Kingdom
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13
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Maeta K, Hattori S, Ikutomo J, Edamatsu H, Bilasy SE, Miyakawa T, Kataoka T. Comprehensive behavioral analysis of mice deficient in Rapgef2 and Rapgef6, a subfamily of guanine nucleotide exchange factors for Rap small GTPases possessing the Ras/Rap-associating domain. Mol Brain 2018; 11:27. [PMID: 29747665 PMCID: PMC5946393 DOI: 10.1186/s13041-018-0370-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 04/29/2018] [Indexed: 12/22/2022] Open
Abstract
Rapgef2 and Rapgef6 define a subfamily of guanine nucleotide exchange factors for Rap small GTPases, characterized by the possession of the Ras/Rap-associating domain. Previous genomic analyses suggested their possible involvement in the etiology of schizophrenia. We recently demonstrated the development of an ectopic cortical mass (ECM), which resembles the human subcortical band heterotopia, in the dorsal telencephalon-specific Rapgef2 conditional knockout (Rapgef2-cKO) brains. Additional knockout of Rapgef6 in Rapgef2-cKO mice resulted in gross enlargement of the ECM whereas knockout of Rapgef6 alone (Rapgef6-KO) had no discernible effect on the brain morphology. Here, we performed a battery of behavioral tests to examine the effects of Rapgef2 or Rapgef6 deficiency on higher brain functions. Rapgef2-cKO mice exhibited hyperlocomotion phenotypes. They showed decreased anxiety-like behavior in the elevated plus maze and the open-field tests as well as increased depression-like behavior in the Porsolt forced swim and tail suspension tests. They also exhibited increased sociability especially in novel environments. They showed defects in cognitive function as evidenced by reduced learning ability in the Barnes circular maze test and by impaired working memory in the T maze tests. In contrast, although Rapgef6 and Rapgef2 share similarities in biochemical roles, Rapgef6-KO mice exhibited mild behavioral abnormalities detected with a number of behavioral tests, such as hyperlocomotion phenotype in the open-field test and the social interaction test with a novel environment and working-memory defects in the T-maze test. In conclusion, although there were differences in their brain morphology and the magnitude of the behavioral abnormalities, Rapgef2-cKO mice and Rapgef6-KO mice exhibited hyperlocomotion phenotype and working-memory defect, both of which could be recognized as schizophrenia-like behavior.
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Affiliation(s)
- Kazuhiro Maeta
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017 Japan
- Present address: Department of Neurotherapeutics, Osaka University Graduate School of Medicine, 2-2Yamadaoka, Suita, Osaka, 565-0871 Japan
| | - Satoko Hattori
- Division of Systems Medical Science, Institute for Comprehensive Medical Science, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi 470-1192 Japan
| | - Junji Ikutomo
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017 Japan
| | - Hironori Edamatsu
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017 Japan
| | - Shymaa E. Bilasy
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017 Japan
- Present address: Department of Biochemistry, Faculty of Pharmacy, Suez Canal University, El-shikh Zayed, Ismailia, 41522 Egypt
| | - Tsuyoshi Miyakawa
- Division of Systems Medical Science, Institute for Comprehensive Medical Science, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi 470-1192 Japan
| | - Tohru Kataoka
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017 Japan
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Egami Y, Araki N. Transient recruitment of M-Ras GTPase to phagocytic cups in RAW264 macrophages during FcγR-mediated phagocytosis. Microscopy (Oxf) 2018; 67:68-74. [DOI: 10.1093/jmicro/dfx131] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 12/17/2017] [Indexed: 12/22/2022] Open
Affiliation(s)
- Youhei Egami
- Department of Histology and Cell Biology, School of Medicine, Kagawa University, Miki, Kagawa 761-0793, Japan
| | - Nobukazu Araki
- Department of Histology and Cell Biology, School of Medicine, Kagawa University, Miki, Kagawa 761-0793, Japan
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Yoshikawa Y, Takano O, Kato I, Takahashi Y, Shima F, Kataoka T. Ras inhibitors display an anti-metastatic effect by downregulation of lysyl oxidase through inhibition of the Ras-PI3K-Akt-HIF-1α pathway. Cancer Lett 2017; 410:82-91. [PMID: 28951129 DOI: 10.1016/j.canlet.2017.09.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 09/07/2017] [Accepted: 09/17/2017] [Indexed: 02/08/2023]
Abstract
Metastasis stands as the major obstacle for the survival from cancers. Nonetheless most existing anti-cancer drugs inhibit only cell proliferation, and discovery of agents having both anti-proliferative and anti-metastatic properties would be more beneficial. We previously reported the discovery of small-molecule Ras inhibitors, represented by Kobe0065, that displayed anti-proliferative activity on xenografts of human colorectal cancer (CRC) cell line SW480 carrying the K-rasG12Vgene. Here we show that treatment of cancer cells carrying the activated ras genes with Kobe0065 or a siRNA targeting Ras downregulates the expression of lysyl oxidase (LOX), which has been implicated in metastasis. LOX expression is enhanced by co-expression of RasG12V through activation of phosphatidylinositol 3-kinase (PI3K)/Akt and concomitant accumulation of hypoxia-inducible factor (HIF)-1α. Furthermore, Kobe0065 effectively inhibits not only migration and invasion of cancer cells carrying the activated ras genes but also lung metastasis of human CRC cell line SW620 carrying the K-rasG12V gene. Collectively, these results indicate that Kobe0065 prevents metastasis through inhibition of the Ras-PI3K-Akt-HIF-1α-LOX signaling and suggest that Ras inhibitors in general might exhibit both anti-proliferative and anti-metastatic properties toward cancer cells carrying the activated ras genes.
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Affiliation(s)
- Yoko Yoshikawa
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan
| | - Osamu Takano
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan
| | - Ichiro Kato
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan
| | - Yoshihisa Takahashi
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan
| | - Fumi Shima
- Drug Discovery Science, Division of Advanced Medical Science, Department of Science, Technology and Innovation, Kobe University Graduate School of Science, Technology and Innovation, Kobe, 650-0017, Japan.
| | - Tohru Kataoka
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan.
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Farag MI, Yoshikawa Y, Maeta K, Kataoka T. Rapgef2, a guanine nucleotide exchange factor for Rap1 small GTPases, plays a crucial role in adherence junction (AJ) formation in radial glial cells through ERK-mediated upregulation of the AJ-constituent protein expression. Biochem Biophys Res Commun 2017; 493:139-145. [PMID: 28917843 DOI: 10.1016/j.bbrc.2017.09.062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 09/13/2017] [Indexed: 11/28/2022]
Abstract
Rapgef2 and Rapgef6 define a subfamily of guanine nucleotide exchange factors for Rap1, characterized by possession of the Ras/Rap-associating domains and implicated in the etiology of schizophrenia. We previously found that dorsal telencephalon-specific Rapgef2 conditional knockout mice exhibits severe defects in formation of apical surface adherence junctions (AJs) and localization of radial glial cells (RGCs). In this study, we analyze the underlying molecular mechanism by using primary cultures of RGCs established from the developing cerebral cortex. The results show that Rapgef2-deficient RGCs exhibit a decreased ability of neurosphere formation, morphological changes represented by regression of radial glial (RG) fibers and reduced expression of AJ-constituent proteins such as N-cadherin, zonula occludens-1, E-cadherin and β-catenin. Moreover, siRNA-mediated knockdown of Rapgef2 or Rap1A inhibits the AJ protein expression and RG fiber formation while overexpression of Rapgef2, Rapgef6, Rap1AG12V or Rap1BG12V in Rapgef2-deficient RGCs restores them. Furthermore, Rapgef2-deficient RGCs exhibit a reduction in phosphorylation of extracellular signal-regulated kinase (ERK) leading to downregulation of the expression of c-jun, which is implicated in the AJ protein expression. These results indicate a crucial role of the Rapgef2-Rap1A-ERK-c-jun pathway in regulation of the AJ formation in RGCs.
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Affiliation(s)
- Maged Ibrahim Farag
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Yoko Yoshikawa
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Kazuhiro Maeta
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Tohru Kataoka
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan.
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Crucial Role of Rapgef2 and Rapgef6, a Family of Guanine Nucleotide Exchange Factors for Rap1 Small GTPase, in Formation of Apical Surface Adherens Junctions and Neural Progenitor Development in the Mouse Cerebral Cortex. eNeuro 2016; 3:eN-NWR-0142-16. [PMID: 27390776 PMCID: PMC4917737 DOI: 10.1523/eneuro.0142-16.2016] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 06/04/2016] [Indexed: 12/19/2022] Open
Abstract
Cerebral neocortex development in mammals requires highly orchestrated events involving proliferation, differentiation, and migration of neural progenitors and neurons. Rapgef2 and Rapgef6 constitute a unique family of guanine nucleotide exchange factors for Rap1 small GTPase, which is known to play crucial roles in migration of postmitotic neurons. We previously reported that conditional knockout of Rapgef2 in dorsal telencephalon (Rapgef2-cKO) resulted in the formation of an ectopic cortical mass (ECM) resembling that of subcortical band heterotopia. Here we show that double knockout of Rapgef6 in Rapgef2-cKO mice (Rapgef2/6-dKO) results in marked enlargement of the ECM. While Rapgef2-cKO affects late-born neurons only, Rapgef2/6-dKO affects both early-born and late-born neurons. The Rapgef2-cKO cortex at embryonic day (E) 15.5, and the Rapgef2/6-dKO cortex at E13.5 and E15.5 show disruption of the adherens junctions (AJs) on the apical surface, detachment of radial glial cells (RGCs) from the apical surface and disorganization of the radial glial fiber system, which are accompanied by aberrant distribution of RGCs and intermediate progenitors, normally located in the ventricular zone and the subventricular zone, respectively, over the entire cerebral cortex. Moreover, intrauterine transduction of Cre recombinase into the Rapgef2flox/flox brains also results in the apical surface AJ disruption and the RGC detachment from the apical surface, both of which are effectively suppressed by cotransduction of the constitutively active Rap1 mutant Rap1G12V. These results demonstrate a cell-autonomous role of the Rapgef2/6-Rap1 pathway in maintaining the apical surface AJ structures, which is necessary for the proper development of neural progenitor cells.
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Deletion of Rapgef6, a candidate schizophrenia susceptibility gene, disrupts amygdala function in mice. Transl Psychiatry 2015; 5:e577. [PMID: 26057047 PMCID: PMC4490285 DOI: 10.1038/tp.2015.75] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 03/22/2015] [Accepted: 04/23/2015] [Indexed: 02/01/2023] Open
Abstract
In human genetic studies of schizophrenia, we uncovered copy-number variants in RAPGEF6 and RAPGEF2 genes. To discern the effects of RAPGEF6 deletion in humans, we investigated the behavior and neural functions of a mouse lacking Rapgef6. Rapgef6 deletion resulted in impaired amygdala function measured as reduced fear conditioning and anxiolysis. Hippocampal-dependent spatial memory and prefrontal cortex-dependent working memory tasks were intact. Neural activation measured by cFOS phosphorylation demonstrated a reduction in hippocampal and amygdala activation after fear conditioning, while neural morphology assessment uncovered reduced spine density and primary dendrite number in pyramidal neurons of the CA3 hippocampal region of knockout mice. Electrophysiological analysis showed enhanced long-term potentiation at cortico-amygdala synapses. Rapgef6 deletion mice were most impaired in hippocampal and amygdalar function, brain regions implicated in schizophrenia pathophysiology. The results provide a deeper understanding of the role of the amygdala in schizophrenia and suggest that RAPGEF6 may be a novel therapeutic target in schizophrenia.
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Liu L, You L, Tan L, Wang DW, Cui W. Genetic insight into the role of MRAS in coronary artery disease risk. Gene 2015; 564:63-6. [PMID: 25800439 DOI: 10.1016/j.gene.2015.03.041] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Revised: 02/10/2015] [Accepted: 03/18/2015] [Indexed: 11/19/2022]
Abstract
The muscle Ras (MRAS) gene polymorphisms have been reported to be associated with coronary artery disease (CAD) in white Europeans. The aim of this study was to ascertain the role of MRAS gene polymorphisms in conferring susceptibility to CAD, and to explore the effect on severity of CAD in Chinese population. We genotyped 5009 Chinese individuals (2466 CAD cases and 2543 controls) for eight single nucleotide polymorphisms (SNPs) around MRAS and used logistic regression analysis to determine whether they were associated with CAD. The association of the SNP loci on the severity of CAD was analyzed using a logistic and linear regression analysis, respectively. Our results revealed that an intron SNP, rs1199337, tends to be marginally associated with CAD as previously reported in Caucasians (nominal P=0.01, OR 1.10, 95% CI 1.01-1.20). However, this association did not retain statistically significant levels after applying Bonferroni's correction for multiple testing (corrected P=0.08). There was no significant association between other loci and CAD (nominal P>0.05). We did not observe any significant association between the SNPs and severity of CAD (all P values>0.05). From the above results, the MRAS gene loci might have a minor effect in conferring susceptibility to CAD in Chinese population.
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Affiliation(s)
- Lei Liu
- Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - Ling You
- Division of Cardiology, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, People's Republic of China
| | - Lun Tan
- Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - Dao Wen Wang
- Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.
| | - Wei Cui
- Division of Cardiology, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, People's Republic of China.
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Structural and mechanistic insights into the recruitment of talin by RIAM in integrin signaling. Structure 2014; 22:1810-1820. [PMID: 25465129 DOI: 10.1016/j.str.2014.09.020] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 09/18/2014] [Accepted: 09/19/2014] [Indexed: 11/22/2022]
Abstract
Plasma membrane (PM)-bound GTPase Rap1 recruits the Rap1-interacting-adaptor-molecule (RIAM), which in turn recruits talin to bind and activate integrins. However, it is unclear how RIAM recruits talin and why its close homolog lamellipodin does not. Here, we report that, although RIAM possesses two talin-binding sites (TBS1 and TBS2), only TBS1 is capable of recruiting cytoplasmic talin to the PM, and the R8 domain is the strongest binding site in talin. Crystal structure of an R7R8:TBS1 complex reveals an unexpected kink in the TBS1 helix that is not shared in the homologous region of lamellipodin. This kinked helix conformation is required for the colocalization of RIAM and talin at the PM and proper activation of integrin. Our findings provide the structural and mechanistic insight into talin recruitment by RIAM that underlies integrin activation and explain the differential functions of the otherwise highly homologous RIAM and lamellipodin in integrin signaling.
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Okada K, Miyake H, Yamaguchi K, Chiba K, Maeta K, Bilasy SE, Edamatsu H, Kataoka T, Fujisawa M. Critical function of RA-GEF-2/Rapgef6, a guanine nucleotide exchange factor for Rap1, in mouse spermatogenesis. Biochem Biophys Res Commun 2014; 445:89-94. [DOI: 10.1016/j.bbrc.2014.01.149] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Accepted: 01/24/2014] [Indexed: 11/28/2022]
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Liu H, Huang XQ, Yang M, Ji XM, Du X, Zheng J. MRAS Genetic Variation Is Associated with Atherothrombotic Stroke in the Han Chinese Population. J Clin Neurol 2013; 9:223-30. [PMID: 24285963 PMCID: PMC3840132 DOI: 10.3988/jcn.2013.9.4.223] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Revised: 04/23/2013] [Accepted: 04/23/2013] [Indexed: 11/25/2022] Open
Abstract
Background and Purpose Atherothrombotic cerebral infarction [atherothrombotic stroke (ATS)] shares common risk factors and pathophysiological mechanisms with coronary artery disease (CAD), and both diseases appear to have common susceptibility loci. The muscle RAS oncogene homolog gene (MRAS) has been identified as a susceptibility locus for CAD and is implicated in atherosclerosis. The aim of this study was to elucidate whether the single-nucleotide polymorphisms (SNPs) and haplotypes of MRAS are associated with increased risk of ATS in a population of Han Chinese. Methods A case-controlled association study was conducted in which only patients with ATS (identified as a major subtype in the Korean modification of the Trial of Org 10172 in Acute Stroke Treatment classification) were enrolled. Subgroup analyses were carried out to determine whether the effect of the MRAS polymorphism was specific to age and gender among the subjects. Results In total, 194 ATS and 186 control subjects were included in the present study. Two tagging SNPs were identified in MRAS (rs40593 and rs3755751). A multivariate regression analysis revealed a positive association between rs40593 and ATS under dominant and additive models after adjustment for covariates. Subgroup analyses revealed that there were no gender differences with respect to allele or genotype frequencies between the groups. The AG genotype for rs40593 (p=0.028), the CT genotype for rs3755751 (p=0.036), and G-allele carriers (AG plus GG) for rs40593 (p=0.015) exhibited a significant protective effect among those aged ≥45 years. For the haplotype analysis, ATS subjects aged ≥45 years had a higher frequency of the ACAC haplotype (76.0%) than the controls (68.1%; p<0.05); that haplotype was associated with an increased risk of ATS. Conclusions The obtained data suggest a positive association between MRAS and ATS among the Han Chinese. Further studies should be performed with larger sample and among different ethnic populations, and gene-gene or gene-environment interactions should be considered.
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Affiliation(s)
- Hua Liu
- Department of Neurology, the Second Clinical Medical College of North Sichuan Medical College, Nanchong, PR China. ; Department of Neurology, Xinqiao Hospital, the Third Military Medical University, Chongqing, PR China
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Loirand G, Sauzeau V, Pacaud P. Small G Proteins in the Cardiovascular System: Physiological and Pathological Aspects. Physiol Rev 2013; 93:1659-720. [DOI: 10.1152/physrev.00021.2012] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Small G proteins exist in eukaryotes from yeast to human and constitute the Ras superfamily comprising more than 100 members. This superfamily is structurally classified into five families: the Ras, Rho, Rab, Arf, and Ran families that control a wide variety of cell and biological functions through highly coordinated regulation processes. Increasing evidence has accumulated to identify small G proteins and their regulators as key players of the cardiovascular physiology that control a large panel of cardiac (heart rhythm, contraction, hypertrophy) and vascular functions (angiogenesis, vascular permeability, vasoconstriction). Indeed, basal Ras protein activity is required for homeostatic functions in physiological conditions, but sustained overactivation of Ras proteins or spatiotemporal dysregulation of Ras signaling pathways has pathological consequences in the cardiovascular system. The primary object of this review is to provide a comprehensive overview of the current progress in our understanding of the role of small G proteins and their regulators in cardiovascular physiology and pathologies.
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Affiliation(s)
- Gervaise Loirand
- INSERM, UMR S1087; University of Nantes; and CHU Nantes, l'Institut du Thorax, Nantes, France
| | - Vincent Sauzeau
- INSERM, UMR S1087; University of Nantes; and CHU Nantes, l'Institut du Thorax, Nantes, France
| | - Pierre Pacaud
- INSERM, UMR S1087; University of Nantes; and CHU Nantes, l'Institut du Thorax, Nantes, France
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Alshahid M, Wakil SM, Al-Najai M, Muiya NP, Elhawari S, Gueco D, Andres E, Hagos S, Mazhar N, Meyer BF, Dzimiri N. New susceptibility locus for obesity and dyslipidaemia on chromosome 3q22.3. Hum Genomics 2013; 7:15. [PMID: 23738802 PMCID: PMC3681549 DOI: 10.1186/1479-7364-7-15] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 05/13/2013] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND The muscle Ras (MRAS) gene resides on chromosome 3q22.3 and encodes a member of the membrane-associated Ras small GTPase proteins, which function as signal transducers in multiple processes including cell growth and differentiation. Its role in cardiovascular disease is not fully understood yet. In a preliminary study in heterozygous familial hypercholesterolaemia, we identified a locus linking the early onset of coronary artery disease (CAD) to chromosome 3q.22 and elected to sequence the MRAS gene using the MegaBACE DNA analysis system. In the present study, we investigated the association of seven single-nucleotide polymorphisms (SNPs) at this locus with CAD and its dyslipidaemia-related risk traits in 4,650 Saudi angiographed individuals using TaqMan assays by the Applied Biosystems real-time Prism 7900HT Sequence Detection System. RESULTS Among the studied SNPs, rs6782181 (p = 0.017) and rs9818870T (p = 0.009) were associated with CAD following adjustment for sex, age and other confounding risk factors. The rs6782181_GG also conferred risk for obesity (1,764 cases vs. 2,586 controls) [1.16(1.03-1.30); p = 0.017], hypercholesterolaemia (1,686 vs. 2,744) [1.23(1.02-1.47); p = 0.019], hypertriglyceridaemia (1,155 vs. 3,496) [1.29(1.01-1.45); p = 0.043] and low high-density lipoprotein-cholesterol (lHDL-chol) levels (1,935 vs. 2,401) [1.15(1.02-1.30); p = 0.023] after adjustment. Additionally, rs253662_(CT+TT) [1.16(1.01-1.32); p = 0.030] was associated with lHDL-chol levels. Interestingly, rs253662 (p = 0.014) and rs6782181 (p = 0.019) were protective against acquiring high low-density lipoprotein-cholesterol (hLDL-chol) levels (p = 0.014), while rs1720819 showed similar effects against CAD (p < 0.0001). More importantly, a 7-mer haplotype, ACCTGAC (χ2 = 7.66; p = 0.0056), constructed from the studied SNPs, its 6-mer derivative CCTGAC (χ2 = 6.90; p = 0.0086) and several other shorter derivatives conferred risk for obesity. hLDL-chol was weakly linked to CTAA (χ2 = 3.79; p = 0.052) and CCT (χ2 = 4.32; p = 0.038), while several other haplotypes were protective against both obesity and hLDL-chol level. CONCLUSION Our results demonstrate that the genomic locus for the MRAS gene confers risk for CAD, obesity and dyslipidaemia and point to the possible involvement of other genes or regulatory elements at this locus, rather than changes in the M-Ras protein function, in these events.
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Affiliation(s)
- Maie Alshahid
- King Faisal Heart Institute, MBC-16, King Faisal Specialist Hospital and Research Centre, Riyadh, 11211, Saudi Arabia
| | - Salma M Wakil
- Genetics Department, MBC-03, King Faisal Specialist Hospital and Research Centre, Riyadh, 11211, Saudi Arabia
| | - Mohammed Al-Najai
- Genetics Department, MBC-03, King Faisal Specialist Hospital and Research Centre, Riyadh, 11211, Saudi Arabia
| | - Nzioka P Muiya
- Genetics Department, MBC-03, King Faisal Specialist Hospital and Research Centre, Riyadh, 11211, Saudi Arabia
| | - Samar Elhawari
- Genetics Department, MBC-03, King Faisal Specialist Hospital and Research Centre, Riyadh, 11211, Saudi Arabia
| | - Daisy Gueco
- Genetics Department, MBC-03, King Faisal Specialist Hospital and Research Centre, Riyadh, 11211, Saudi Arabia
| | - Editha Andres
- Genetics Department, MBC-03, King Faisal Specialist Hospital and Research Centre, Riyadh, 11211, Saudi Arabia
| | - Samia Hagos
- Genetics Department, MBC-03, King Faisal Specialist Hospital and Research Centre, Riyadh, 11211, Saudi Arabia
| | - Nejat Mazhar
- Genetics Department, MBC-03, King Faisal Specialist Hospital and Research Centre, Riyadh, 11211, Saudi Arabia
| | - Brian F Meyer
- King Faisal Heart Institute, MBC-16, King Faisal Specialist Hospital and Research Centre, Riyadh, 11211, Saudi Arabia
| | - Nduna Dzimiri
- Genetics Department, MBC-03, King Faisal Specialist Hospital and Research Centre, Riyadh, 11211, Saudi Arabia
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McGuire MF, Sriram Iyengar M, Mercer DW. Data driven linear algebraic methods for analysis of molecular pathways: application to disease progression in shock/trauma. J Biomed Inform 2012; 45:372-87. [PMID: 22200681 PMCID: PMC3346262 DOI: 10.1016/j.jbi.2011.12.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Revised: 12/09/2011] [Accepted: 12/10/2011] [Indexed: 12/24/2022]
Abstract
MOTIVATION Although trauma is the leading cause of death for those below 45years of age, there is a dearth of information about the temporal behavior of the underlying biological mechanisms in those who survive the initial trauma only to later suffer from syndromes such as multiple organ failure. Levels of serum cytokines potentially affect the clinical outcomes of trauma; understanding how cytokine levels modulate intra-cellular signaling pathways can yield insights into molecular mechanisms of disease progression and help to identify targeted therapies. However, developing such analyses is challenging since it necessitates the integration and interpretation of large amounts of heterogeneous, quantitative and qualitative data. Here we present the Pathway Semantics Algorithm (PSA), an algebraic process of node and edge analyses of evoked biological pathways over time for in silico discovery of biomedical hypotheses, using data from a prospective controlled clinical study of the role of cytokines in multiple organ failure (MOF) at a major US trauma center. A matrix algebra approach was used in both the PSA node and PSA edge analyses with different matrix configurations and computations based on the biomedical questions to be examined. In the edge analysis, a percentage measure of crosstalk called XTALK was also developed to assess cross-pathway interference. RESULTS In the node/molecular analysis of the first 24h from trauma, PSA uncovered seven molecules evoked computationally that differentiated outcomes of MOF or non-MOF (NMOF), of which three molecules had not been previously associated with any shock/trauma syndrome. In the edge/molecular interaction analysis, PSA examined four categories of functional molecular interaction relationships--activation, expression, inhibition, and transcription--and found that the interaction patterns and crosstalk changed over time and outcome. The PSA edge analysis suggests that a diagnosis, prognosis or therapy based on molecular interaction mechanisms may be most effective within a certain time period and for a specific functional relationship.
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Affiliation(s)
- Mary F McGuire
- Department of Pathology and Laboratory Medicine, Medical School, University of Texas Health Science Center at Houston, Houston, TX, USA.
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Cheng YC, Anderson CD, Bione S, Keene K, Maguire JM, Nalls M, Rasheed A, Zeginigg M, Attia J, Baker R, Barlera S, Biffi A, Bookman E, Brott TG, Brown RD, Chen F, Chen WM, Ciusani E, Cole JW, Cortellini L, Danesh J, Doheny K, Ferrucci L, Grazia Franzosi M, Frossard P, Furie KL, Golledge J, Hankey GJ, Hernandez D, Holliday EG, Hsu FC, Jannes J, Kamal A, Khan MS, Kittner SJ, Koblar SA, Lewis M, Lincz L, Lisa A, Matarin M, Moscato P, Mychaleckyj JC, Parati EA, Parolo S, Pugh E, Rost NS, Schallert M, Schmidt H, Scott RJ, Sturm JW, Yadav S, Zaidi M, Boncoraglio GB, Levi CR, Meschia JF, Rosand J, Sale M, Saleheen D, Schmidt R, Sharma P, Worrall B, Mitchell BD. Are myocardial infarction--associated single-nucleotide polymorphisms associated with ischemic stroke? Stroke 2012; 43:980-6. [PMID: 22363065 PMCID: PMC3622211 DOI: 10.1161/strokeaha.111.632075] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Accepted: 11/23/2011] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Ischemic stroke (IS) shares many common risk factors with coronary artery disease (CAD). We hypothesized that genetic variants associated with myocardial infarction (MI) or CAD may be similarly involved in the etiology of IS. To test this hypothesis, we evaluated whether single-nucleotide polymorphisms (SNPs) at 11 different loci recently associated with MI or CAD through genome-wide association studies were associated with IS. METHODS Meta-analyses of the associations between the 11 MI-associated SNPs and IS were performed using 6865 cases and 11 395 control subjects recruited from 9 studies. SNPs were either genotyped directly or imputed; in a few cases a surrogate SNP in high linkage disequilibrium was chosen. Logistic regression was performed within each study to obtain study-specific βs and standard errors. Meta-analysis was conducted using an inverse variance weighted approach assuming a random effect model. RESULTS Despite having power to detect odds ratio of 1.09-1.14 for overall IS and 1.20-1.32 for major stroke subtypes, none of the SNPs were significantly associated with overall IS and/or stroke subtypes after adjusting for multiple comparisons. CONCLUSIONS Our results suggest that the major common loci associated with MI risk do not have effects of similar magnitude on overall IS but do not preclude moderate associations restricted to specific IS subtypes. Disparate mechanisms may be critical in the development of acute ischemic coronary and cerebrovascular events.
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Affiliation(s)
- Yu-Ching Cheng
- Department of Medicine, University of Maryland School of Medicine, 660 W Redwood St, Howard Hall, Room 492, Baltimore, MD 21201, USA
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27
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Ellis KL, Frampton CM, Pilbrow AP, Troughton RW, Doughty RN, Whalley GA, Ellis CJ, Skelton L, Thomson J, Yandle TG, Richards AM, Cameron VA. Genomic Risk Variants at 1p13.3, 1q41, and 3q22.3 Are Associated With Subsequent Cardiovascular Outcomes in Healthy Controls and in Established Coronary Artery Disease. ACTA ACUST UNITED AC 2011; 4:636-46. [DOI: 10.1161/circgenetics.111.960336] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
Genome-wide association studies have identified gene variants associated with coronary artery disease risk; however, whether they affect disease progression is largely unknown. This study investigated associations between polymorphisms at 1p13.3 (rs599839), 1q41 (rs17465637), and 3q22.3 (rs9818870) and cardiovascular outcomes in healthy volunteers and in patients with established heart disease.
Methods and Results—
Canterbury Healthy Volunteer study (HV) (n=1649), Coronary Disease Cohort Study (CDCS) (n=1797), and Post-Myocardial Infarction study (PMI) (n=906) participants (New Zealand), were genotyped for rs599839, rs9818870, and rs17465637. Associations between genotype and anthropometric characteristics, neurohormonal analysis, echocardiography, and clinical outcomes over medium-long-term follow-up (median HV, 5.9 years; CDCS, 3.7 years; PMI, 11.3 years) were tested. At 1p13.3, HV and CDCS participants carrying 1 or more rs599839 G allele had a lower prevalence of dyslipidemia (
P
≤0.005) or lower levels of low-density lipoprotein (
P
=0.031) and total (
P
=0.004) cholesterol and/or less history of myocardial infarction (
P
≤0.04) compared with AA participants. Moreover, CDCS and PMI AG/GG participants had better cardiac function as indicated by echocardiography (
P
≤0.026), and fewer CDCS AG/GG participants were readmitted for a non-ST-segment elevation MI (
P
=0.012) during follow-up. The polymorphism at 1q41 (rs17465637) was associated with better cardiovascular outcomes in the HV (
P
=0.028) and PMI (
P
=0.008) cohorts, and 3q22.3 (rs9818870) was a predictor of death/admission in the HV cohort (
P
=0.045).
Conclusions—
These data suggest that coronary artery disease genomic risk variants at 1p13.3 and 1q41 are associated with subsequent clinical outcome in heart patients and confirm rs9818870 at 3q22.3 as a predictor of cardiovascular risk in individuals free of overt heart disease.
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Affiliation(s)
- Katrina L. Ellis
- From the Christchurch Cardioendocrine Research Group, Department of Medicine, University of Otago-Christchurch, Christchurch, New Zealand (K.L.E., C.M.F., A.P.P., R.W.T., L.S., J.T., T.G.Y., A.M.R., V.A.C.); Department of Medicine, Faculty of Medicine and Health Sciences, University of Auckland, Auckland, New Zealand (R.N.D., G.A.W., C.J.E.), and Department of Medical Imaging, Unitec Institute of Technology, Auckland, New Zealand (G.A.W.)
| | - Chris M. Frampton
- From the Christchurch Cardioendocrine Research Group, Department of Medicine, University of Otago-Christchurch, Christchurch, New Zealand (K.L.E., C.M.F., A.P.P., R.W.T., L.S., J.T., T.G.Y., A.M.R., V.A.C.); Department of Medicine, Faculty of Medicine and Health Sciences, University of Auckland, Auckland, New Zealand (R.N.D., G.A.W., C.J.E.), and Department of Medical Imaging, Unitec Institute of Technology, Auckland, New Zealand (G.A.W.)
| | - Anna P. Pilbrow
- From the Christchurch Cardioendocrine Research Group, Department of Medicine, University of Otago-Christchurch, Christchurch, New Zealand (K.L.E., C.M.F., A.P.P., R.W.T., L.S., J.T., T.G.Y., A.M.R., V.A.C.); Department of Medicine, Faculty of Medicine and Health Sciences, University of Auckland, Auckland, New Zealand (R.N.D., G.A.W., C.J.E.), and Department of Medical Imaging, Unitec Institute of Technology, Auckland, New Zealand (G.A.W.)
| | - Richard W. Troughton
- From the Christchurch Cardioendocrine Research Group, Department of Medicine, University of Otago-Christchurch, Christchurch, New Zealand (K.L.E., C.M.F., A.P.P., R.W.T., L.S., J.T., T.G.Y., A.M.R., V.A.C.); Department of Medicine, Faculty of Medicine and Health Sciences, University of Auckland, Auckland, New Zealand (R.N.D., G.A.W., C.J.E.), and Department of Medical Imaging, Unitec Institute of Technology, Auckland, New Zealand (G.A.W.)
| | - Rob N. Doughty
- From the Christchurch Cardioendocrine Research Group, Department of Medicine, University of Otago-Christchurch, Christchurch, New Zealand (K.L.E., C.M.F., A.P.P., R.W.T., L.S., J.T., T.G.Y., A.M.R., V.A.C.); Department of Medicine, Faculty of Medicine and Health Sciences, University of Auckland, Auckland, New Zealand (R.N.D., G.A.W., C.J.E.), and Department of Medical Imaging, Unitec Institute of Technology, Auckland, New Zealand (G.A.W.)
| | - Gillian A. Whalley
- From the Christchurch Cardioendocrine Research Group, Department of Medicine, University of Otago-Christchurch, Christchurch, New Zealand (K.L.E., C.M.F., A.P.P., R.W.T., L.S., J.T., T.G.Y., A.M.R., V.A.C.); Department of Medicine, Faculty of Medicine and Health Sciences, University of Auckland, Auckland, New Zealand (R.N.D., G.A.W., C.J.E.), and Department of Medical Imaging, Unitec Institute of Technology, Auckland, New Zealand (G.A.W.)
| | - Chris J. Ellis
- From the Christchurch Cardioendocrine Research Group, Department of Medicine, University of Otago-Christchurch, Christchurch, New Zealand (K.L.E., C.M.F., A.P.P., R.W.T., L.S., J.T., T.G.Y., A.M.R., V.A.C.); Department of Medicine, Faculty of Medicine and Health Sciences, University of Auckland, Auckland, New Zealand (R.N.D., G.A.W., C.J.E.), and Department of Medical Imaging, Unitec Institute of Technology, Auckland, New Zealand (G.A.W.)
| | - Lorraine Skelton
- From the Christchurch Cardioendocrine Research Group, Department of Medicine, University of Otago-Christchurch, Christchurch, New Zealand (K.L.E., C.M.F., A.P.P., R.W.T., L.S., J.T., T.G.Y., A.M.R., V.A.C.); Department of Medicine, Faculty of Medicine and Health Sciences, University of Auckland, Auckland, New Zealand (R.N.D., G.A.W., C.J.E.), and Department of Medical Imaging, Unitec Institute of Technology, Auckland, New Zealand (G.A.W.)
| | - Judith Thomson
- From the Christchurch Cardioendocrine Research Group, Department of Medicine, University of Otago-Christchurch, Christchurch, New Zealand (K.L.E., C.M.F., A.P.P., R.W.T., L.S., J.T., T.G.Y., A.M.R., V.A.C.); Department of Medicine, Faculty of Medicine and Health Sciences, University of Auckland, Auckland, New Zealand (R.N.D., G.A.W., C.J.E.), and Department of Medical Imaging, Unitec Institute of Technology, Auckland, New Zealand (G.A.W.)
| | - Tim G. Yandle
- From the Christchurch Cardioendocrine Research Group, Department of Medicine, University of Otago-Christchurch, Christchurch, New Zealand (K.L.E., C.M.F., A.P.P., R.W.T., L.S., J.T., T.G.Y., A.M.R., V.A.C.); Department of Medicine, Faculty of Medicine and Health Sciences, University of Auckland, Auckland, New Zealand (R.N.D., G.A.W., C.J.E.), and Department of Medical Imaging, Unitec Institute of Technology, Auckland, New Zealand (G.A.W.)
| | - A. Mark Richards
- From the Christchurch Cardioendocrine Research Group, Department of Medicine, University of Otago-Christchurch, Christchurch, New Zealand (K.L.E., C.M.F., A.P.P., R.W.T., L.S., J.T., T.G.Y., A.M.R., V.A.C.); Department of Medicine, Faculty of Medicine and Health Sciences, University of Auckland, Auckland, New Zealand (R.N.D., G.A.W., C.J.E.), and Department of Medical Imaging, Unitec Institute of Technology, Auckland, New Zealand (G.A.W.)
| | - Vicky A. Cameron
- From the Christchurch Cardioendocrine Research Group, Department of Medicine, University of Otago-Christchurch, Christchurch, New Zealand (K.L.E., C.M.F., A.P.P., R.W.T., L.S., J.T., T.G.Y., A.M.R., V.A.C.); Department of Medicine, Faculty of Medicine and Health Sciences, University of Auckland, Auckland, New Zealand (R.N.D., G.A.W., C.J.E.), and Department of Medical Imaging, Unitec Institute of Technology, Auckland, New Zealand (G.A.W.)
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Bilasy SE, Satoh T, Terashima T, Kataoka T. RA-GEF-1 (Rapgef2) is essential for proper development of the midline commissures. Neurosci Res 2011; 71:200-9. [PMID: 21864586 DOI: 10.1016/j.neures.2011.08.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Revised: 08/02/2011] [Accepted: 08/04/2011] [Indexed: 12/22/2022]
Abstract
The cerebral hemispheres are directly connected by three major interhemispheric fibers: the corpus callosum, the anterior commissure, and the hippocampal commissure. RA-GEF-1 (also termed Rapgef2) is a guanine nucleotide exchange factor responsible for sustained activation of Rap1. We previously reported anatomical defects of the major forebrain commissures in the adult dorsal telencephalon-specific RA-GEF-1 conditional knockout (cKO) mice. In this study, we use neuroanatomical tracing and immunohistochemistry to study the formation of the commissural fibers during early postnatal development. DiI anterograde tracing reveals the inability of the callosal axons to cross the midline in cKO mice, thereby forming Probst bundles on the ipsilateral side, which is associated with the absence of the indusium griseum glia and the glial sling at the cortical midline. Wheat germ agglutinin-conjugated horseradish peroxidase retrograde tracing verifies the agenesis of the anterior commissure in cKO mice, and DiI anterograde tracing confirms the deviation of the fibers from their original tract. As for the hippocampal commissure, agenesis and hypoplasia are observed in its dorsal and ventral parts, respectively. These results indicate the essential role of RA-GEF-1 in the proper formation of the cerebral midline commissures.
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Affiliation(s)
- Shymaa E Bilasy
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan
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29
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Gloerich M, Bos JL. Regulating Rap small G-proteins in time and space. Trends Cell Biol 2011; 21:615-23. [PMID: 21820312 DOI: 10.1016/j.tcb.2011.07.001] [Citation(s) in RCA: 120] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Revised: 06/29/2011] [Accepted: 07/05/2011] [Indexed: 11/25/2022]
Abstract
Signaling by the small G-protein Rap is under tight regulation by its GEFs and GAPs. These are multi-domain proteins that are themselves controlled by distinct upstream pathways, and thus couple different extra- and intracellular cues to Rap. The individual RapGEFs and RapGAPs are, in addition, targeted to specific cellular locations by numerous anchoring mechanisms and, consequently, may control different pools of Rap. Here, we review the various activating signals and targeting mechanisms of these proteins and discuss their contribution to the spatiotemporal regulation and biological functions of the Rap proteins.
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Affiliation(s)
- Martijn Gloerich
- Molecular Cancer Research, Centre for Biomedical Genetics and Cancer Genomics Centre, University Medical Center Utrecht, Utrecht, The Netherlands
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30
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de la Vega M, Burrows JF, Johnston JA. Ubiquitination: Added complexity in Ras and Rho family GTPase function. Small GTPases 2011; 2:192-201. [PMID: 22145091 DOI: 10.4161/sgtp.2.4.16707] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Revised: 07/08/2011] [Accepted: 07/08/2011] [Indexed: 12/17/2022] Open
Abstract
The regulation of the small GTPases leading to their membrane localization has long been attributed to processing of their C-terminal CAAX box. As deregulation of many of these GTPases have been implicated in cancer and other disorders, prenylation and methylation of this CAAX box has been studied in depth as a possibility for drug targeting, but unfortunately, to date no drug has proved clinically beneficial. However, these GTPases also undergo other modifications that may be important for their regulation. Ubiquitination has long been demonstrated to regulate the fate of numerous cellular proteins and recently it has become apparent that many GTPases, along with their GAPs, GeFs and GDis, undergo ubiquitination leading to a variety of fates such as re-localization or degradation. in this review we focus on the recent literature demonstrating that the regulation of small GTPases by ubiquitination, either directly or indirectly, plays a considerable role in controlling their function and that targeting these modifications could be important for disease treatment.
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Affiliation(s)
- Michelle de la Vega
- Centre for Infection and Immunity; School of Medicine, Dentistry and Biomedical Sciences; Queen's University; Belfast, UK
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31
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Ogawa N, Imai Y, Morita H, Nagai R. Genome-wide association study of coronary artery disease. Int J Hypertens 2010; 2010:790539. [PMID: 20981302 PMCID: PMC2958466 DOI: 10.4061/2010/790539] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2010] [Accepted: 06/25/2010] [Indexed: 02/05/2023] Open
Abstract
Coronary artery disease (CAD) is a multifactorial disease with environmental and genetic determinants. The genetic determinants of CAD have previously been explored by the candidate gene approach. Recently, the data from the International HapMap Project and the development of dense genotyping chips have enabled us to perform genome-wide association studies (GWAS) on a large number of subjects without bias towards any particular candidate genes. In 2007, three chip-based GWAS simultaneously revealed the significant association between common variants on chromosome 9p21 and CAD. This association was replicated among other ethnic groups and also in a meta-analysis. Further investigations have detected several other candidate loci associated with CAD. The chip-based GWAS approach has identified novel and unbiased genetic determinants of CAD and these insights provide the important direction to better understand the pathogenesis of CAD and to develop new and improved preventive measures and treatments for CAD.
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Affiliation(s)
- Naomi Ogawa
- Department of Cardiovascular Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo Bunkyo-ku, Tokyo 113-8655, Japan
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32
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BAG3 directly associates with guanine nucleotide exchange factor of Rap1, PDZGEF2, and regulates cell adhesion. Biochem Biophys Res Commun 2010; 400:413-8. [PMID: 20800573 DOI: 10.1016/j.bbrc.2010.08.092] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Accepted: 08/21/2010] [Indexed: 11/22/2022]
Abstract
BAG3, a member of the Hsc70 binding co-chaperone BAG-family proteins, has critical roles in regulating actin organization, cell adhesion, cell motility and tumor metastasis. The PDZ domain containing guanine nucleotide exchange factor 2 (PDZGEF2) was cloned as a BAG3-interacting protein. PDZGEF2 induces activation of Rap1 and increases integrin-mediated cell adhesion. The PPDY motif at the C-terminus of PDZGEF2 binds to the WW domain of BAG3 in vitro and in vivo. BAG3 deletion mutant lacking the WW domain lose its cell adhesion and motility activity. Gene knockdown of PDZGEF2 leads to the loss of cell adhesion on fibronectin-coated plates while BAG3 overexpression increases cell adhesion in Cos7 cells, but not in PDZGEF2 gene knockdown cells indicating that PDZGEF2 is a critical partner for BAG3 in regulating cell adhesion.
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33
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Rap1, a mercenary among the Ras-like GTPases. Dev Biol 2010; 340:1-9. [PMID: 20060392 DOI: 10.1016/j.ydbio.2009.12.043] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Revised: 12/28/2009] [Accepted: 12/30/2009] [Indexed: 01/07/2023]
Abstract
The small Ras-like GTPase Rap1 is an evolutionary conserved protein that originally gained interest because of its capacity to revert the morphological phenotype of Ras-transformed fibroblasts. Rap1 is regulated by a large number of stimuli that include growth factors and cytokines, but also physical force and osmotic stress. Downstream of Rap1, a plethora of effector molecules has been proposed on the basis of biochemical studies. Here, we present an overview of genetic studies on Rap1 in various model organisms and relate the observed phenotypes to in vitro studies. The picture that emerges is one in which Rap1 is a versatile regulator of morphogenesis, by regulating diverse processes that include establishment of cellular polarity, cell-matrix interactions and cell-cell adhesion. Surprisingly, genetic experiments indicate that in the various model organisms, Rap1 uses distinct effector molecules that impinge upon the actin cytoskeleton and adhesion molecules.
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34
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Genetic basis of myocardial infarction: Novel insights from genome-wide association studies. CURRENT CARDIOVASCULAR RISK REPORTS 2009. [DOI: 10.1007/s12170-009-0063-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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35
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Watanabe-Takano H, Takano K, Keduka E, Endo T. M-Ras is activated by bone morphogenetic protein-2 and participates in osteoblastic determination, differentiation, and transdifferentiation. Exp Cell Res 2009; 316:477-90. [PMID: 19800879 DOI: 10.1016/j.yexcr.2009.09.028] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2009] [Revised: 09/26/2009] [Accepted: 09/28/2009] [Indexed: 11/19/2022]
Abstract
The small GTPase M-Ras is highly expressed in the central nervous system and plays essential roles in neuronal differentiation. However, its other cellular and physiological functions remain to be elucidated. Here, we clarify the novel functions of M-Ras in osteogenesis. M-Ras was prominently expressed in developing mouse bones particularly in osteoblasts and hypertrophic chondrocytes. Its expression was elevated in C3H/10T1/2 (10T1/2) mesenchymal cells and in MC3T3-E1 preosteoblasts during differentiation into osteoblasts. Treatment of C2C12 skeletal muscle myoblasts with bone morphogenetic protein-2 (BMP-2) to bring about transdifferentiation into osteoblasts also induced M-Ras mRNA and protein expression. Moreover, the BMP-2 treatment activated the M-Ras protein. Stable expression of the constitutively active M-Ras(G22V) in 10T1/2 cells facilitated osteoblast differentiation. M-Ras(G22V) also induced transdifferentiation of C2C12 cells into osteoblasts. In contrast, knockdown of endogenous M-Ras by RNAi interfered with osteoblast differentiation in 10T1/2 and MC3T3-E1 cells. Osteoblast differentiation in M-Ras(G22V)-expressing C2C12 cells was inhibited by treatment with inhibitors of p38 MAP kinase (MAPK) and c-Jun N-terminal kinase (JNK) but not by inhibitors of MAPK and ERK kinase (MEK) or phosphatidylinositol 3-kinase. These results imply that M-Ras, induced and activated by BMP-2 signaling, participates in the osteoblastic determination, differentiation, and transdifferentiation under p38 MAPK and JNK regulation.
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Affiliation(s)
- Haruko Watanabe-Takano
- Department of Biology, Graduate School of Science, Chiba University, Inageku, Chiba 263-8522, Japan
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36
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Kanemura H, Satoh T, Bilasy SE, Ueda S, Hirashima M, Kataoka T. Impaired vascular development in the yolk sac and allantois in mice lacking RA-GEF-1. Biochem Biophys Res Commun 2009; 387:754-9. [PMID: 19635461 DOI: 10.1016/j.bbrc.2009.07.108] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2009] [Accepted: 07/22/2009] [Indexed: 11/27/2022]
Abstract
RA-GEF-1 is a guanine nucleotide exchange factor for the small GTPase Rap1. RA-GEF-1 knockout mice show defects in vascular development starting around 7.5days post coitum and die by 9.5days post coitum. Here, we employed in vitro culture systems for allantois explants and endothelial cells to gain insights into the mechanism for RA-GEF-1-mediated regulation of embryonic vascular network formation. The development of the vascular plexus and the accumulation of VE-cadherin at cell-cell junctions were significantly impaired in the RA-GEF-1 knockout allantois and yolk sac. Rap1 activation as visualized by an activation-specific probe was also diminished by RA-GEF-1 knockout. Reduced accumulation of VE-cadherin at cell-cell junctions and defects in blood vessel formation in vitro due to the lack of RA-GEF-1 were suppressed by ectopic expression of constitutively activated Rap1. Overall, these results suggest the involvement of Rap1 downstream of RA-GEF-1 in the regulation of vascular network formation in mouse embryos.
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Affiliation(s)
- Hoshimi Kanemura
- Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kusunoki-cho, Chuo-ku, Japan
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Erdmann J, Grosshennig A, Braund PS, König IR, Hengstenberg C, Hall AS, Linsel-Nitschke P, Kathiresan S, Wright B, Trégouët DA, Cambien F, Bruse P, Aherrahrou Z, Wagner AK, Stark K, Schwartz SM, Salomaa V, Elosua R, Melander O, Voight BF, O'Donnell CJ, Peltonen L, Siscovick DS, Altshuler D, Merlini PA, Peyvandi F, Bernardinelli L, Ardissino D, Schillert A, Blankenberg S, Zeller T, Wild P, Schwarz DF, Tiret L, Perret C, Schreiber S, El Mokhtari NE, Schäfer A, März W, Renner W, Bugert P, Klüter H, Schrezenmeir J, Rubin D, Ball SG, Balmforth AJ, Wichmann HE, Meitinger T, Fischer M, Meisinger C, Baumert J, Peters A, Ouwehand WH, Deloukas P, Thompson JR, Ziegler A, Samani NJ, Schunkert H. New susceptibility locus for coronary artery disease on chromosome 3q22.3. Nat Genet 2009; 41:280-2. [PMID: 19198612 PMCID: PMC2695543 DOI: 10.1038/ng.307] [Citation(s) in RCA: 391] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2008] [Accepted: 12/01/2008] [Indexed: 11/09/2022]
Abstract
We present a three-stage analysis of genome-wide SNP data in 1,222 German individuals with myocardial infarction and 1,298 controls, in silico replication in three additional genome-wide datasets of coronary artery disease (CAD) and subsequent replication in approximately 25,000 subjects. We identified one new CAD risk locus on 3q22.3 in MRAS (P = 7.44 x 10(-13); OR = 1.15, 95% CI = 1.11-1.19), and suggestive association with a locus on 12q24.31 near HNF1A-C12orf43 (P = 4.81 x 10(-7); OR = 1.08, 95% CI = 1.05-1.11).
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Affiliation(s)
- Jeanette Erdmann
- Medizinische Klinik II, Universität zu Lübeck, 23538 Lübeck, Germany.
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Cell-cell junction formation: the role of Rap1 and Rap1 guanine nucleotide exchange factors. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1788:790-6. [PMID: 19159611 DOI: 10.1016/j.bbamem.2008.12.010] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2008] [Revised: 12/15/2008] [Accepted: 12/16/2008] [Indexed: 01/09/2023]
Abstract
Rap proteins are Ras-like small GTP-binding proteins that amongst others are involved in the control of cell-cell and cell-matrix adhesion. Several Rap guanine nucleotide exchange factors (RapGEFs) function to activate Rap. These multi-domain proteins, which include C3G, Epacs, PDZ-GEFs, RapGRPs and DOCK4, are regulated by various different stimuli and may function at different levels in junction formation. Downstream of Rap, a number of effector proteins have been implicated in junctional control, most notably the adaptor proteins AF6 and KRIT/CCM1. In this review, we will highlight the latest findings on the Rap signaling network in the control of epithelial and endothelial cell-cell junctions.
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Abstract
Ras and Rap proteins are closely related small GTPases. Whereas Ras is known for its role in cell proliferation and survival, Rap1 is predominantly involved in cell adhesion and cell junction formation. Ras and Rap are regulated by different sets of guanine nucleotide exchange factors and GTPase-activating proteins, determining one level of specificity. In addition, although the effector domains are highly similar, Rap and Ras interact with largely different sets of effectors, providing a second level of specificity. In this review, we discuss the regulatory proteins and effectors of Ras and Rap, with a focus on those of Rap.
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Affiliation(s)
- Judith H Raaijmakers
- Department of Physiological Chemistry, Centre for Biomedical Genetics, Universitair Medisch Centrum Utrecht, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands
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Dubé N, Kooistra MRH, Pannekoek WJ, Vliem MJ, Oorschot V, Klumperman J, Rehmann H, Bos JL. The RapGEF PDZ-GEF2 is required for maturation of cell-cell junctions. Cell Signal 2008; 20:1608-15. [PMID: 18585005 DOI: 10.1016/j.cellsig.2008.05.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2008] [Accepted: 05/11/2008] [Indexed: 11/25/2022]
Abstract
The small G-protein Rap1 is a critical regulator of cell-cell contacts and is activated by the remodeling of adherens junctions. Here we identify the Rap1 guanine nucleotide exchange factor PDZ-GEF2 as an upstream activator of Rap1 required for the maturation of adherens junctions in the lung carcinoma cells A549. Knockdown of PDZ-GEF2 results in the persistence of adhesion zippers at cell-cell contacts. Activation of Rap1A rescues junction maturation in absence of PDZ-GEF2, demonstrating that Rap1A is downstream of PDZ-GEF2 in this process. Moreover, depletion of Rap1A, but not Rap1B, impairs adherens junction maturation. siRNA for PDZ-GEF2 also lowers the levels of E-cadherin, an effect that can be mimicked by Rap1B, but not Rap1A siRNA. Since junctions in Rap1B depleted cells have a mature appearance, these data suggest that PDZ-GEF2 activates Rap1A and Rap1B to perform different functions. Our results present the first direct evidence that PDZ-GEF2 plays a critical role in the maturation of adherens junctions.
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Affiliation(s)
- Nadia Dubé
- Department of Physiological Chemistry, Centre for Biomedical Genetics and Cancer Genomics Centre, Utrecht, The Netherlands
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Ikuta S, Edamatsu H, Li M, Hu L, Kataoka T. Crucial Role of Phospholipase Cε in Skin Inflammation Induced by Tumor-Promoting Phorbol Ester. Cancer Res 2008; 68:64-72. [DOI: 10.1158/0008-5472.can-07-3245] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Wei P, Satoh T, Edamatsu H, Aiba A, Setsu T, Terashima T, Kitazawa S, Nakao K, Yoshikawa Y, Tamada M, Kataoka T. Defective vascular morphogenesis and mid-gestation embryonic death in mice lacking RA-GEF-1. Biochem Biophys Res Commun 2007; 363:106-12. [PMID: 17826737 DOI: 10.1016/j.bbrc.2007.08.149] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2007] [Accepted: 08/21/2007] [Indexed: 11/18/2022]
Abstract
A multitude of guanine nucleotide exchange factors (GEFs) regulate Rap1 small GTPases, however, their individual functions remain obscure. Here, we investigate the in vivo function of the Rap1 GEF RA-GEF-1. The expression of RA-GEF-1 in wild-type mice starts at embryonic day (E) 8.5, and continues thereafter. RA-GEF-1(-/-) mice appear normal until E7.5, but become grossly abnormal and dead by E9.5. This mid-gestation death appears to be closely associated with severe defects in yolk sac blood vessel formation. RA-GEF-1(-/-) yolk sacs form apparently normal blood islands by E8.5, but the blood islands fail to coalesce into a primary vascular plexus, indicating that vasculogenesis is impaired. Furthermore, RA-GEF-1(-/-) embryos proper show severe defects in the formation of major blood vessels. These results suggest that deficient Rap1 signaling may lead to defective vascular morphogenesis in the yolk sac and embryos proper.
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Affiliation(s)
- Ping Wei
- Division of Molecular Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan
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