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Aleksic B, Kushima I, Hashimoto R, Ohi K, Ikeda M, Yoshimi A, Nakamura Y, Ito Y, Okochi T, Fukuo Y, Yasuda Y, Fukumoto M, Yamamori H, Ujike H, Suzuki M, Inada T, Takeda M, Kaibuchi K, Iwata N, Ozaki N. Analysis of the VAV3 as candidate gene for schizophrenia: evidences from voxel-based morphometry and mutation screening. Schizophr Bull 2013; 39:720-8. [PMID: 22416266 PMCID: PMC3627762 DOI: 10.1093/schbul/sbs038] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
In recently completed Japanese genome-wide association studies (GWAS) of schizophrenia (JPN_GWAS) one of the top association signals was detected in the region of VAV3, a gene that maps to the chromosome 1p13.3. In order to complement JPN_GWAS findings, we tested the association of rs1410403 with brain structure in healthy individuals and schizophrenic patients and performed exon resequencing of VAV3. We performed voxel-based morphometry (VBM) and mutation screening of VAV3. Four independent samples were used in the present study: (1) for VBM analysis, we used case-control sample comprising 100 patients with schizophrenia and 264 healthy controls, (2) mutation analysis was performed on a total of 321 patients suffering from schizophrenia, and 2 case-control samples (3) 729 unrelated patients with schizophrenia and 564 healthy comparison subjects, and (4) sample comprising 1511 cases and 1517 healthy comparison subjects and were used for genetic association analysis of novel coding variants with schizophrenia. The VBM analysis suggests that rs1410403 might affect the volume of the left superior and middle temporal gyri (P=.011 and P=.013, respectively), which were reduced in patients with schizophrenia compared with healthy subjects. Moreover, 4 rare novel missense variants were detected. The mutations were followed-up in large independent sample, and one of the novel variants (Glu741Gly) was associated with schizophrenia (P=.02). These findings demonstrate that VAV3 can be seen as novel candidate gene for schizophrenia in which both rare and common variants may be related to increased genetic risk for schizophrenia in Japanese population.
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Affiliation(s)
- Branko Aleksic
- Department of Psychiatry, Graduate School of Medicine, Nagoya University, Nagoya, Japan,Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan
| | - Itaru Kushima
- Department of Psychiatry, Graduate School of Medicine, Nagoya University, Nagoya, Japan,Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan
| | | | - Kazutaka Ohi
- Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan,Department of Psychiatry, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Masashi Ikeda
- Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan,Department of Psychiatry, School of Medicine, Fujita Health University, 1-98 Dengakugakubo,Kutsukake-cho,Toyoake, Aichi 470-1192, Japan
| | - Akira Yoshimi
- Department of Psychiatry, Graduate School of Medicine, Nagoya University, Nagoya, Japan,Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan
| | - Yukako Nakamura
- Department of Psychiatry, Graduate School of Medicine, Nagoya University, Nagoya, Japan,Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan
| | - Yoshihito Ito
- Department of Psychiatry, Graduate School of Medicine, Nagoya University, Nagoya, Japan,Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan
| | - Tomo Okochi
- Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan,Department of Psychiatry, School of Medicine, Fujita Health University, 1-98 Dengakugakubo,Kutsukake-cho,Toyoake, Aichi 470-1192, Japan
| | - Yasuhisa Fukuo
- Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan,Department of Psychiatry, School of Medicine, Fujita Health University, 1-98 Dengakugakubo,Kutsukake-cho,Toyoake, Aichi 470-1192, Japan
| | - Yuka Yasuda
- Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan,Department of Psychiatry, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Motoyuki Fukumoto
- Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan,Department of Psychiatry, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Hidenaga Yamamori
- Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan,Department of Psychiatry, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Hiroshi Ujike
- Department of Neuropsychiatry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Michio Suzuki
- Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan,Department of Neuropsychiatry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Toshiya Inada
- Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan,Seiwa Hospital, Institute of Neuropsychiatry, Tokyo, Japan
| | - Masatoshi Takeda
- Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan,Department of Psychiatry, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Kozo Kaibuchi
- Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan,Department of Cell Pharmacology, Graduate School of Medicine, Nagoya University, Nagoya, Japan
| | - Nakao Iwata
- Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan,Department of Psychiatry, School of Medicine, Fujita Health University, 1-98 Dengakugakubo,Kutsukake-cho,Toyoake, Aichi 470-1192, Japan,To whom correspondence should be addressed; tel: 81-562-93-2000, fax: 81-562-93-1831, e-mail:
| | - Norio Ozaki
- Department of Psychiatry, Graduate School of Medicine, Nagoya University, Nagoya, Japan,Core Research for Evolutional Science and Technology, Japan Science and Technology Corporation, Tokyo, Japan
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Shah OJ, Antonetti DA, Kimball SR, Jefferson LS. Leucine, glutamine, and tyrosine reciprocally modulate the translation initiation factors eIF4F and eIF2B in perfused rat liver. J Biol Chem 1999; 274:36168-75. [PMID: 10593901 DOI: 10.1074/jbc.274.51.36168] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Leucine, glutamine, and tyrosine, three amino acids playing key modulatory roles in hepatic proteolysis, were evaluated for activation of signaling pathways involved in regulation of liver protein synthesis. Furthermore, because leucine signals to effectors that lie distal to the mammalian target of rapamycin, these downstream factors were selected for study as candidate mediators of amino acid signaling. Using the perfused rat liver as a model system, we observed a 25% stimulation of protein synthesis in response to balanced hyperaminoacidemia, whereas amino acid imbalance due to elevated concentrations of leucine, glutamine, and tyrosine resulted in a protein synthetic depression of roughly 50% compared with normoaminoacidemic controls. The reduction in protein synthesis accompanying amino acid imbalance became manifest at high physiologic concentrations and was dictated by the guanine nucleotide exchange activity of translation initiation factor eIF2B. Paradoxically, this phenomenon occurred concomitantly with assembly of the mRNA cap recognition complex, eIF4F as well as activation of the 70-kDa ribosomal S6 kinase, p70(S6k). Dual and reciprocal modulation of eIF4F and eIF2B was leucine-specific because isoleucine, a structural analog, was ineffective in these regards. Thus, we conclude that amino acid imbalance, heralded by leucine, initiates a liver-specific translational fail-safe mechanism that deters protein synthesis under unfavorable circumstances despite promotion of the eIF4F complex.
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Affiliation(s)
- O J Shah
- Department of Cellular and Molecular Physiology, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania 17033, USA
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Price NT, Mellor H, Craddock BL, Flowers KM, Kimball SR, Wilmer T, Jefferson LS, Proud CG. eIF2B, the guanine nucleotide-exchange factor for eukaryotic initiation factor 2. Sequence conservation between the alpha, beta and delta subunits of eIF2B from mammals and yeast. Biochem J 1996; 318 ( Pt 2):637-43. [PMID: 8929216 PMCID: PMC1217679 DOI: 10.1042/bj3180637] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The guanine nucleotide-exchange factor eIF2B mediates the exchange of GDP bound to translation initiation factor eIF2 for GTP. This exchange process is a key regulatory step for the control of translation initiation in eukaryotic organisms. To improve our understanding of the structure, function and regulation of eIF2B, we have obtained and sequenced cDNA species encoding all of its five subunits. Here we report the sequences of eIF2B beta and delta from rat. This paper focuses on sequence similarities between the alpha, beta and delta subunits of mammalian eIF2B. Earlier work showed that the amino acid sequences of the corresponding subunits of eIF2B in the yeast Saccharomyces cerevisiae (GCN3, GCD7 and GCD2) exhibit considerable similarity. We demonstrate that this is also true for the mammalian subunits. Moreover, alignment of the eIF2B alpha, beta and delta sequences from mammals and yeast, along with the sequence of the putative eIF2B alpha subunit from Caenorhabditis elegans and eIF2B delta from Schizosaccharomyces pombe shows that a large number of residues are identical or conserved between the C-terminal regions of all these sequences. This strong sequence conservation points to the likely functional importance of these residues. The implications of this are discussed in the light of results concerning the functions of the subunits of eIF2B in yeast and mammals. Our results also indicate that the large apparent differences in mobility on SDS/PAGE between eIF2B beta and delta subunits from rat and rabbit are not due to differences in their lengths but reflect differences in amino acid composition. We have also examined the relative expression of mRNA species encoding the alpha, beta, delta and epsilon subunits of eIF2B in a range of rat tissues by Northern blot analysis. As might be expected for mRNA species encoding subunits of a heterotrimeric protein, the ratios of expression levels of these subunits to one another did not vary between the different rat tissues examined (with the possible exception of liver). This represents the first analysis of the levels of expression of mRNA species encoding the different subunits of eIF2B.
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Affiliation(s)
- N T Price
- Department of Biochemistry, University of Bristol, U.K
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