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Takumi S, Tomioka M, Yunoki Y, Eto R, Komatsu Y, Shiozaki K, Komatsu M. Microcystin-LR-induced epithelial-mesenchymal transition-like cells acquire resistance to multi-toxins. Toxicon 2024; 238:107592. [PMID: 38163460 DOI: 10.1016/j.toxicon.2023.107592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/15/2023] [Accepted: 12/29/2023] [Indexed: 01/03/2024]
Abstract
The protein phosphatase inhibitor microcystin-LR (MC-LR), a hepatocyte-selective cyanotoxin, induces phenotypic changes in HEK293 OATP1B3-expressing (HEK293-OATP1B3) cells, which include cytoskeletal reorganization (HEK293-OATP1B3-AD) and anoikis resistance (HEK293-OATP1B3-FL) transformed cells, respectively. These cells acquire resistance to MC-LR and partial epithelial-mesenchymal transition (EMT) characteristics. In cancer cells, EMT is generally involved in multi-drug resistance. Here, we focused on the multi-drug resistance of HEK293-OATP1B3-AD and HEK293-OATP1B3-FL cells. The MTT assay and immunoblotting were conducted to examine the responses of HEK293-OATP1B3, HEK293-OATP1B3-AD, and HEK293-OATP1B3-FL cells to multiple toxins and drugs that function as substrates for OATP1B3, including MC-LR, nodularin (Nod), okadaic acid (OA), and cisplatin (CDDP). HEK293-OATP1B3-AD and HEK293-OATP1B3-FL cells were more resistant to MC-LR, Nod, and OA than HEK293-OATP1B3 cells. Conversely, the three cell types were equivalently sensitive to CDDP. By using protein phosphatase assay, the reduction of the inhibitory effect of MC-LR and Nod on phosphatase activity might be one reason for the resistance to MC-LR and Nod in HEK293-OATP1B3-AD and HEK293-OATP1B3-FL cells. Furthermore, the parental HEK293-OATP1B3 cells showed enhanced p53 phosphorylation and stabilization after MC-LR exposure, while p53 phosphorylation was attenuated in HEK293-OATP1B3-AD and HEK293-OATP1B3-FL cells. Moreover, in HEK293-OATP1B3-AD and HEK293-OATP1B3-FL cells, AKT phosphorylation was higher than that of the parental HEK293-OATP1B3 cell line. These results suggest that the multi-toxin resistance observed in HEK293-OATP1B3-AD and HEK293-OATP1B3-FL cells is associated with AKT activation and p53 inactivation.
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Affiliation(s)
- Shota Takumi
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 890-0056, Kagoshima, Japan; The United Graduate School of Agricultural Sciences, Kagoshima University, 890-8580, Kagoshima, Japan
| | - Masaru Tomioka
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 890-0056, Kagoshima, Japan
| | - Yasunari Yunoki
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 890-0056, Kagoshima, Japan
| | - Risa Eto
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 890-0056, Kagoshima, Japan
| | - Yumiko Komatsu
- Department of Domestic Science, Kagoshima Women's College, 890-8565, Kagoshima, Japan
| | - Kazuhiro Shiozaki
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 890-0056, Kagoshima, Japan; The United Graduate School of Agricultural Sciences, Kagoshima University, 890-8580, Kagoshima, Japan
| | - Masaharu Komatsu
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 890-0056, Kagoshima, Japan; The United Graduate School of Agricultural Sciences, Kagoshima University, 890-8580, Kagoshima, Japan.
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Takumi S, Hashimoto K, Tomioka M, Sato M, He W, Komatsu Y, Aoki S, Ikeda R, Shiozaki K, Furukawa T, Komatsu M. Acteoside from Conandron ramondioides Reduces Microcystin-LR Cytotoxicity by Inhibiting Intracellular Uptake Mediated by OATP1B3. Planta Med 2023; 89:616-623. [PMID: 36626925 DOI: 10.1055/a-1978-8768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The hepatotoxin microcystin-LR is a strong inhibitor of serine/threonine protein phosphatase (PP) 1 and PP2A. The onset of its cytotoxicity depends on its selective uptake via the hepatocyte uptake transporters, organic anion transporting polypeptide (OATP) 1B1 and OATP1B3. Understanding and preventing the cytotoxicity of microcystin-LR is crucial to maintain human health. This chemoprevention study demonstrates that the herbal plant extract of iwajisha (20 µg/mL) reduced microcystin-LR cytotoxicity in OATP1B3-expressing cells by approximately six times. In addition, 20 µM acteoside, which is one of the major compounds in iwajisha, reduced microcystin-LR cytotoxicity by approximately 7.4 times. Acteoside could also reduce the cytotoxicity of other compounds, such as okadaic acid and nodularin, which are both substrates of OATP1B3 and inhibitors of PP1/PP2A. To investigate the mechanism by which the cytotoxicity of microcystin-LR is attenuated by acteosides, microcystin-LR and microcystin-LR-binding proteins in cells were examined after microcystin-LR and acteosides were co-exposed. Thus, acteoside noncompetitively inhibited microcystin-LR uptake by OATP1B3-expressing cells. Furthermore, acteoside inhibited the intracellular interaction of microcystin-LR with its binding protein(s), including the 22 kDa protein. Furthermore, using immunoblot analysis, acteoside induced the phosphorylation of extracellular signal-regulated kinase (ERK), which is one of the survival signaling molecules. These results suggest that acteoside reduces microcystin-LR cytotoxicity through several mechanisms, including the inhibition of microcystin-LR uptake via OATP1B3, and decreased interaction between microcystin-LR and its binding protein(s), and that ERK signaling activation contributes to the attenuation effect of acteoside against microcystin-LR cytotoxicity.
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Affiliation(s)
- Shota Takumi
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima, Japan
- The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan
| | - Kairi Hashimoto
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima, Japan
| | - Masaru Tomioka
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima, Japan
| | - Mina Sato
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima, Japan
| | - Weijie He
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima, Japan
| | - Yumiko Komatsu
- Department of Domestic Science, Kagoshima Women's College, Kagoshima, Japan
| | - Shunji Aoki
- Department of Pharmacy, School of Pharmacy, Hyogo Medical University, Kobe, Japan
| | - Ryuji Ikeda
- Department of Pharmacy, University of Miyazaki Hospital, Miyazaki, Japan
| | - Kazuhiro Shiozaki
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima, Japan
- The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan
| | - Tatsuhiko Furukawa
- Department of Pathology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Masaharu Komatsu
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima, Japan
- The United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan
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Takumi S, Shimono T, Ikema S, Hotta Y, Chigwechokha PK, Shiozaki K, Sugiyama Y, Hashimoto M, Furukawa T, Komatsu M. Overexpression of carboxylesterase contributes to the attenuation of cyanotoxin microcystin-LR toxicity. Comp Biochem Physiol C Toxicol Pharmacol 2017; 194:22-27. [PMID: 28163251 DOI: 10.1016/j.cbpc.2017.01.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 01/31/2017] [Accepted: 01/31/2017] [Indexed: 02/02/2023]
Abstract
Microcystin-LR is a hepatotoxin produced by several cyanobacteria. Its toxicity is mainly due to a inhibition of protein phosphatase, PP1 and PP2A. Previously, we used a cell line stably expressing uptake transporter for microcystin-LR, OATP1B3 (HEK293-OATP1B3 cells). In this study, to determine whether overexpression of carboxylesterase (CES), which degrades ester-group and amide-group, attenuates the cytotoxicity of microcystin-LR, we generated the HEK293-OATP1B3/CES2 double-transfected cells. HEK293-OATP1B3/CES2 cells showed high hydrolysis activity of p-nitrophenyl acetate (PNPA), which is an authentic substrate for esterase. CES activity in HEK293-OATP1B3/CES2 cells was approximately 3-fold higher than that in the HEK293-OATP1B3 cells. HEK293-OATP1B3/CES2 cells (IC50: 25.4±7.7nM) showed approximately 2.1-fold resistance to microcystin-LR than HEK293-OATP1B3 cells (IC50: 12.0±1.5nM). Moreover, the CES inhibition assay and microcystin-agarose pull down assay showed the possibility of the interaction between CES2 and microcystin-LR. Our results indicated that the overexpression of CES2 attenuates the cytotoxicity of microcystin-LR via interaction with microcystin-LR.
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Affiliation(s)
- Shota Takumi
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 890-0056 Kagoshima, Japan; Department of Domestic Science, Kagoshima Women's College, Kagoshima 890-8565, Japan
| | - Tai Shimono
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 890-0056 Kagoshima, Japan
| | - Satoshi Ikema
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 890-0056 Kagoshima, Japan
| | - Yuki Hotta
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 890-0056 Kagoshima, Japan
| | - Petros K Chigwechokha
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 890-0056 Kagoshima, Japan
| | - Kazuhiro Shiozaki
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 890-0056 Kagoshima, Japan
| | - Yasumasa Sugiyama
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 890-0056 Kagoshima, Japan
| | - Mitsuru Hashimoto
- College of Pharmaceutical Sciences, School of Clinical Pharmacy, Matsuyama University, 790-8578, Ehime, Japan
| | - Tatsuhiko Furukawa
- Department of Molecular Oncology, Graduate School of Medical and Dental Sciences, Kagoshima University, 890-8544 Kagoshima, Japan; Center for the Research of Advanced Diagnosis and Therapy of Cancer, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8544, Japan
| | - Masaharu Komatsu
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 890-0056 Kagoshima, Japan.
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Nohara K, Suzuki T, Okamura K, Matsushita J, Takumi S. Tumor-augmenting effects of gestational arsenic exposure on F1 and F2 in mice. Genes Environ 2017; 39:3. [PMID: 28265304 PMCID: PMC5331735 DOI: 10.1186/s41021-016-0069-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 12/08/2016] [Indexed: 02/08/2023] Open
Abstract
The consequences of early-life exposure to chemicals in the environment are emerging concerns. Chronic exposure to naturally occurring inorganic arsenic has been known to cause various adverse health effects, including cancers, in humans. On the other hand, animal studies by Dr. M. Waalkes’ group reported that arsenite exposure of pregnant F0 females, only from gestational day 8 to 18, increased hepatic tumors in the F1 (arsenite-F1) males of C3H mice, whose males tend to develop spontaneous hepatic tumors later in life. Since this mice model illuminated novel unidentified consequences of arsenic exposure, we wished to further investigate the background mechanisms. In the same experimental model, we identified a variety of factors that were affected by gestational arsenic exposure, including epigenetic and genetic changes, as possible constituents of multiple steps of late-onset hepatic tumor augmentation in arsenite-F1 males. Furthermore, our study discovered that the F2 males born to arsenite-F1 males developed hepatic tumors at a significantly higher rate than the control F2 males. The results imply that the tumor augmenting effect is inherited by arsenite-F2 males through the sperm of arsenite-F1. In this article, we summarized our studies on the consequences of gestational arsenite exposure in F1 and F2 mice to discuss novel aspects of biological effects of gestational arsenic exposure.
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Affiliation(s)
- Keiko Nohara
- Center for Health and Environmental Risk Research, National Institute for Environmental Studies, Tsukuba, 305-8506 Japan
| | - Takehiro Suzuki
- Center for Health and Environmental Risk Research, National Institute for Environmental Studies, Tsukuba, 305-8506 Japan
| | - Kazuyuki Okamura
- Center for Health and Environmental Risk Research, National Institute for Environmental Studies, Tsukuba, 305-8506 Japan
| | - Junya Matsushita
- Center for Health and Environmental Risk Research, National Institute for Environmental Studies, Tsukuba, 305-8506 Japan.,Graduate School of Pharmaceutical Science, Tokyo University of Science, Noda, 278-8510 Japan
| | - Shota Takumi
- Department of Domestic Science, Kagoshima Women's College, Kagoshima, 890-8565 Japan
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Suzuki T, Takumi S, Okamura K, Nohara K. [Biological effects of arsenic and diseases: The mechanisms involved in arsenic-induced carcinogenesis]. Nihon Rinsho 2016; 74:1207-1213. [PMID: 27455813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Chronic arsenic exposure is associated with many diseases, including cancers. Our study using in vivo assay in gpt-delta transgenic mice showed that arsenic particularly induces G : C to T : A transversions, a mutation type induced through oxidative-stress-induced 8-OHdG formation. Gestational arsenic exposure of C3H mice was reported to increase hepatic tumor incidence. We showed that gestational arsenic exposure increased hepatic tumors having activated oncogene Ha-ras by C to A mutation. We also showed that DNA methylation status of Fosb region is implicated in tumor augmentation by gestational arsenic exposure. We further showed that long-term arsenic exposure induces premature senescence. Recent studies reported that senescence is involved in not only tumor suppression, but also tumorgenesis. All these effects of arsenic might be involved in arsenic-induced carcinogenesis.
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Funahashi A, Komatsu M, Furukawa T, Yoshizono Y, Yoshizono H, Orikawa Y, Takumi S, Shiozaki K, Hayashi S, Kaminishi Y, Itakura T. Eel green fluorescent protein is associated with resistance to oxidative stress. Comp Biochem Physiol C Toxicol Pharmacol 2016; 181-182:35-9. [PMID: 26746389 DOI: 10.1016/j.cbpc.2015.12.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 12/16/2015] [Accepted: 12/19/2015] [Indexed: 11/24/2022]
Abstract
Green fluorescent protein (GFP) from eel (Anguilla japonica) muscle (eelGFP) is unique in the vertebrates and requires bilirubin as a ligand to emit fluorescence. This study was performed to clarify the physiological function of the unique GFP. Investigation of susceptibility to oxidative stress was carried out using three types of cell lines including jellyfish (Aequorea coerulescens) GFP (jfGFP)-, or eel GFP (eelGFP)-expressing HEK293 cells, and control vector-transfected HEK293 cells. Binding of eelGFP to bilirubin was confirmed by the observation of green fluorescence in HEK293-eelGFP cells. The growth rate was compared with the three types of cells in the presence or absence of phenol red which possessed antioxidant activity. The growth rates of HEK293-CV and HEK293-jfGFP under phenol red-free conditions were reduced to 52 and 31% of those under phenol red. Under the phenol red-free condition, HEK293-eelGFP had a growth rate of approximately 70% of the phenol red-containing condition. The eelGFP-expressing cells were approximately 2-fold resistant to oxidative stress such as H2O2 exposure. The fluorescence intensity partially decreased or disappeared after exposure to H2O2, and heterogeneous intensity of fluorescence was also observed in isolated eel skeletal muscle cells. These results suggested eelGFP, but not jfGFP, coupled with bilirubin provided the antioxidant activity to the cells as compared to non-bound free bilirubin.
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Affiliation(s)
- Aki Funahashi
- Laboratory of Marine Biotechnology, Faculty of Fisheries, Kagoshima University, 4-50-20 Shimoarata, Kagoshima 890-0056, Japan
| | - Masaharu Komatsu
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 4-50-20 Shimoarata, Kagoshima 890-0056, Japan.
| | - Tatsuhiko Furukawa
- Department of Molecular Oncology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544, Japan; Center for the Research of Advanced Diagnosis and Therapy of Cancer, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544, Japan
| | - Yuki Yoshizono
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 4-50-20 Shimoarata, Kagoshima 890-0056, Japan
| | - Hikari Yoshizono
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 4-50-20 Shimoarata, Kagoshima 890-0056, Japan
| | - Yasuhiro Orikawa
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 4-50-20 Shimoarata, Kagoshima 890-0056, Japan
| | - Shota Takumi
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 4-50-20 Shimoarata, Kagoshima 890-0056, Japan; Department of Domestic Science, Kagoshima Women's College, Kagoshima 890-8565, Japan
| | - Kazuhiro Shiozaki
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 4-50-20 Shimoarata, Kagoshima 890-0056, Japan
| | - Seiichi Hayashi
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 4-50-20 Shimoarata, Kagoshima 890-0056, Japan
| | - Yoshio Kaminishi
- Laboratory of Marine Biotechnology, Faculty of Fisheries, Kagoshima University, 4-50-20 Shimoarata, Kagoshima 890-0056, Japan
| | - Takao Itakura
- Laboratory of Marine Biotechnology, Faculty of Fisheries, Kagoshima University, 4-50-20 Shimoarata, Kagoshima 890-0056, Japan
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Nohara K, Okamura K, Suzuki T, Murai H, Ito T, Shinjo K, Takumi S, Michikawa T, Kondo Y, Hata K. Augmenting effects of gestational arsenite exposure of C3H mice on the hepatic tumors of the F₂ male offspring via the F₁ male offspring. J Appl Toxicol 2015; 36:105-12. [PMID: 25825268 DOI: 10.1002/jat.3149] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 02/13/2015] [Accepted: 02/17/2015] [Indexed: 02/06/2023]
Abstract
Gestational exposure can affect the F2 generation through exposure of F1 germline cells. Previous studies reported that arsenite exposure of only F0 females during their pregnancy increases hepatic tumors in the F1 males in C3H mice, whose males are predisposed spontaneously to develop hepatic tumors later in life. The present study addressed the effects of gestational arsenite exposure on tumorigenesis of the F2 males in C3H mice. Expression analysis of several genes in the normal livers at 53 and 80 weeks of age clearly showed significant changes in the F2 males obtained by crossing gestational arsenite-exposed F1 (arsenite-F1) males and females compared to the control F2 males. Some of the changes were shown to occur in a late-onset manner. Then the tumor incidence was assessed at 75-82 weeks of age in the F2 males obtained by reciprocal crossing between the control and arsenite-F1 males and females. The results demonstrated that the F2 males born to arsenite-F1 males developed tumors at a significantly higher rate than the F2 males born to the control F1 males, irrespective of exposure of F1 females. Gene expressions of hepatocellular carcinoma markers β-catenin (CTNNB1) and interleukin-1 receptor antagonist in the tumors were significantly upregulated in the F2 males born to arsenite-F1 males compared to those born to the control F1 males. These results show that arsenite exposure of only F0 pregnant mice causes late-onset changes and augments tumors in the livers of the F2 males by affecting the F1 male offspring.
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Affiliation(s)
- Keiko Nohara
- Center for Environmental Health Sciences, National Institute for Environmental Studies, Tsukuba, Japan
| | - Kazuyuki Okamura
- Center for Environmental Health Sciences, National Institute for Environmental Studies, Tsukuba, Japan
| | - Takehiro Suzuki
- Center for Environmental Health Sciences, National Institute for Environmental Studies, Tsukuba, Japan
| | - Hikari Murai
- Center for Environmental Health Sciences, National Institute for Environmental Studies, Tsukuba, Japan
| | - Takaaki Ito
- Department of Pathology and Experimental Medicine, Kumamoto University Graduate School of Medical Sciences, Kumamoto, Japan
| | - Keiko Shinjo
- Department of Epigenomics, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Shota Takumi
- Department of Public Health and Environmental Medicine, The Jikei University School of Medicine, Tokyo, Japan
| | - Takehiro Michikawa
- Center for Environmental Health Sciences, National Institute for Environmental Studies, Tsukuba, Japan
| | - Yutaka Kondo
- Department of Epigenomics, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Kenichiro Hata
- Department of Maternal-Fetal Biology, National Research Institute for Child Health and Development, Tokyo, Japan
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Takumi S, Ikema S, Hanyu T, Shima Y, Kurimoto T, Shiozaki K, Sugiyama Y, Park HD, Ando S, Furukawa T, Komatsu M. Naringin attenuates the cytotoxicity of hepatotoxin microcystin-LR by the curious mechanisms to OATP1B1- and OATP1B3-expressing cells. Environ Toxicol Pharmacol 2015; 39:974-981. [PMID: 25818985 DOI: 10.1016/j.etap.2015.02.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 02/24/2015] [Accepted: 02/27/2015] [Indexed: 06/04/2023]
Abstract
Microcystin-LR, which is an inhibitor of serine/threonine protein phosphatase (PP)1 and PP2A, induces liver injury by its selective uptake system into the hepatocyte. It is also thought that microcystin-LR induces reactive oxygen species (ROS). We tried to establish the chemical prevention of microcystin-LR poisoning. We investigated the effect of grapefruit flavanone glycoside naringin on cytotoxicity of microcystin-LR using human hepatocyte uptake transporter OATP1B3-expressing HEK293-OATP1B3 cells. We found cytotoxicity of microcystin-LR was attenuated by naringin in a dose dependent manner. The inhibition magnitude of total cellular serine/threonine protein phosphatase activity induced by microcystin-LR was suppressed by naringin. In addition, uptake of microcystin-LR into HEK293-OATP1B3 cells was inhibited by naringin. Furthermore, microcystin-LR induced phosphorylation of p53 was inhibited by naringin. Regardless of the difference in the exposure pattern of pre-processing and post-processing of naringin, the toxicity of microcystin-LR was comparable. These results suggested that naringin is promising remedy as well as preventive medicine for liver damage with microcystin-LR. In addition, involvement of ROS production after exposure to the sublethal concentrations of microcystin-LR in the onset of cytotoxicity was negligible. Therefore, inhibition of microcystin-LR uptake and the pathway other than ROS production would be involved in the effect of naringin on the attenuation of microcystin-LR toxicity.
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Affiliation(s)
- Shota Takumi
- Department of Public Health and Environmental Medicine, The Jikei University School of Medicine, Tokyo 105-8461, Japan
| | - Satoshi Ikema
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima 890-0056, Japan
| | - Tamami Hanyu
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima 890-0056, Japan; Department of Environmental Sciences, Faculty of Science, Shinshu University, Matsumoto 390-8621, Japan
| | - Yusuke Shima
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima 890-0056, Japan
| | - Takashi Kurimoto
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima 890-0056, Japan
| | - Kazuhiro Shiozaki
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima 890-0056, Japan
| | - Yasumasa Sugiyama
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima 890-0056, Japan
| | - Ho-Dong Park
- Department of Environmental Sciences, Faculty of Science, Shinshu University, Matsumoto 390-8621, Japan
| | - Seiichi Ando
- Department of Nutritional Sciences, Faculty of Health and Welfare Science, Nayoro City University, Nayoro, Hokkaido 096-8641, Japan
| | - Tatsuhiko Furukawa
- Department of Molecular Oncology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544, Japan; Center for the Research of Advanced Diagnosis and Therapy of Cancer, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8544, Japan
| | - Masaharu Komatsu
- Division of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima 890-0056, Japan.
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Takumi S, Okamura K, Yanagisawa H, Sano T, Kobayashi Y, Nohara K. The effect of a methyl-deficient diet on the global DNA methylation and the DNA methylation regulatory pathways. J Appl Toxicol 2015; 35:1550-6. [PMID: 25690533 DOI: 10.1002/jat.3117] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 11/14/2014] [Accepted: 12/12/2014] [Indexed: 12/30/2022]
Abstract
Methyl-deficient diets are known to induce various liver disorders, in which DNA methylation changes are implicated. Recent studies have clarified the existence of the active DNA demethylation pathways that start with oxidization of 5-methylcytosine (5meC) to 5-hydroxymethylcytosine by ten-eleven translocation (Tet) enzymes, followed by the action of base-excision-repair pathways. Here, we investigated the effects of a methionine-choline-deficient (MCD) diet on the hepatic DNA methylation of mice by precisely quantifying 5meC using a liquid chromatography-electrospray ionization-mass spectrometry and by investigating the regulatory pathways, including DNA demethylation. Although feeding the MCD diet for 1 week induced hepatic steatosis and lower level of the methyl donor S-adenosylmethionine, it did not cause a significant reduction in the 5meC content. On the other hand, the MCD diet significantly upregulated the gene expression of the Tet enzymes, Tet2 and Tet3, and the base-excision-repair enzymes, thymine DNA glycosylase and apurinic/apyrimidinic-endonuclease 1. At the same time, the gene expression of DNA methyltransferase 1 and a, was also significantly increased by the MCD diet. These results suggest that the DNA methylation level is precisely regulated even when dietary methyl donors are restricted. Methyl-deficient diets are well known to induce oxidative stress and the oxidative-stress-induced DNA damage, 8-hydroxy-2'-deoxyguanosine (8OHdG), is reported to inhibit DNA methylation. In this study, we also clarified that the increase in 8OHdG number per DNA by the MCD diet is approximately 10 000 times smaller than the reduction in 5meC number, suggesting the contribution of 8OHdG formation to DNA methylation would not be significant.
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Affiliation(s)
- Shota Takumi
- Center for Environmental Health Sciences, National Institute for Environmental Studies, Tsukuba, 305-8506, Japan.,Department of Public Health and Environmental Medicine, The Jikei University School of Medicine, Tokyo, 105-8461, Japan
| | - Kazuyuki Okamura
- Center for Environmental Health Sciences, National Institute for Environmental Studies, Tsukuba, 305-8506, Japan
| | - Hiroyuki Yanagisawa
- Department of Public Health and Environmental Medicine, The Jikei University School of Medicine, Tokyo, 105-8461, Japan
| | - Tomoharu Sano
- Center for Environmental Measurement and Analysis, National Institute for Environmental Studies, Tsukuba, 305-8506, Japan
| | - Yayoi Kobayashi
- Center for Environmental Health Sciences, National Institute for Environmental Studies, Tsukuba, 305-8506, Japan
| | - Keiko Nohara
- Center for Environmental Health Sciences, National Institute for Environmental Studies, Tsukuba, 305-8506, Japan
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10
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Inokuchi A, Yamamoto R, Morita F, Takumi S, Matsusaki H, Ishibashi H, Tominaga N, Arizono K. Effects of lithium on growth, maturation, reproduction and gene expression in the nematodeCaenorhabditis elegans. J Appl Toxicol 2015; 35:999-1006. [DOI: 10.1002/jat.3058] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 06/27/2014] [Accepted: 06/27/2014] [Indexed: 11/09/2022]
Affiliation(s)
- Ayako Inokuchi
- Graduate School of Environmental and Symbiotic Science; Prefectural University of Kumamoto; 3-1-100 Tsukide Kumamoto 862-8502 Japan
| | - Ryoko Yamamoto
- Graduate School of Environmental and Symbiotic Science; Prefectural University of Kumamoto; 3-1-100 Tsukide Kumamoto 862-8502 Japan
| | - Fumiyo Morita
- Graduate School of Environmental and Symbiotic Science; Prefectural University of Kumamoto; 3-1-100 Tsukide Kumamoto 862-8502 Japan
| | - Shota Takumi
- Faculty of Environmental and Symbiotic Sciences; Prefectural University of Kumamoto; 3-1-100 Tsukide Kumamoto 862-8502 Japan
| | - Hiromi Matsusaki
- Faculty of Environmental and Symbiotic Sciences; Prefectural University of Kumamoto; 3-1-100 Tsukide Kumamoto 862-8502 Japan
| | - Hiroshi Ishibashi
- Department of Food and Nutrition; Shokei University Junior College; Kuhonji 2-6-78 Kumamoto 862-8678 Japan
| | - Nobuaki Tominaga
- Department of Chemical and Biological Engineering; Ariake National College of Technology; 150 Higashi-hagio-machi, Omuta Fukuoka 836-8585 Japan
| | - Koji Arizono
- Faculty of Environmental and Symbiotic Sciences; Prefectural University of Kumamoto; 3-1-100 Tsukide Kumamoto 862-8502 Japan
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11
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Nohara K, Suzuki T, Takumi S, Okamura K. Increase in incidence of hepatic tumors caused by oncogenic somatic mutation in mice maternally exposed to inorganic arsenic and the multigenerational and transgenerational effects of inorganic arsenic. Nihon Eiseigaku Zasshi 2015; 69:92-6. [PMID: 24858502 DOI: 10.1265/jjh.69.92] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Inorganic arsenic is a natural environmental contaminant and known to be a human carcinogen. Although rodent models are pivotal in elucidating the mode of action of arsenic, it has been difficult to verify the carcinogenicity of arsenic in rodents until recently. Waalkes et al. (Toxicol Appl Pharmacol 2003;
186:7-17) reported that maternal exposure to arsenite increases the incidence of hepatic tumors in the male pups of C3H mice in adulthood. This finding indicated that the gestational period is vulnerable to arsenic. Using the same experimental model, we found that maternal arsenite exposure increases the incidence of hepatic tumors caused by a somatic mutation of the C61A Ha-ras gene, which encodes an activated oncogenic Ha-ras protein. The G:C to T:A transversion is attributable to oxidative stress. Our further studies of gpt delta transgenic mice, which enable detection of in vivo mutation, and genome-wide analysis of DNA methylation levels using the methylated DNA immunoprecipitation-CpG island microarray method suggest that oxidative-stress-induced mutation and DNA methylation changes are involved in the tumor augmentation in the pups maternally exposed to arsenic. Our recent study has also suggested that maternal arsenic exposure increases the incidence of hepatic tumors even in the grandchildren (the F2 generation). Consideration should be given to multigenerational and transgenerational effects of maternal exposure in future studies.
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Affiliation(s)
- Keiko Nohara
- Center for Environmental Health Sciences, National Institute for Environmental Studies
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Abumhadi N, Kamenarova K, Todorovska E, Dimov G, Takumi S, Nakamura C, Anzai H, Atanassov A. Effects of Three Promoters in Barley Transformation by Particle Bombardment of Mature and Immature Embryos. BIOTECHNOL BIOTEC EQ 2014. [DOI: 10.1080/13102818.2005.10817155] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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13
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Naydenov N, Takumi S, Sugie A, Ogihara Y, Atanassov A, Nakamura C. Structural Diversity of the Wheat Nuclear GeneWaox1aEncoding Mitochondrial Alternative Oxidase, A Single Unique Enzyme In The Cyanide-Resistant Alternative Pathway. BIOTECHNOL BIOTEC EQ 2014. [DOI: 10.1080/13102818.2005.10817153] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Suzuki T, Yamashita S, Ushijima T, Takumi S, Sano T, Michikawa T, Nohara K. Genome-wide analysis of DNA methylation changes induced by gestational arsenic exposure in liver tumors. Cancer Sci 2013; 104:1575-85. [PMID: 24118411 DOI: 10.1111/cas.12298] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Revised: 09/23/2013] [Accepted: 09/28/2013] [Indexed: 12/30/2022] Open
Abstract
Inorganic arsenic is known to be a human carcinogen. Previous studies have reported that DNA methylation changes are involved in arsenic-induced carcinogenesis, therefore, DNA methylation changes that are specific to arsenic-induced tumors would be useful to distinguish tumors induced by arsenic from tumors caused by other factors and to dissect arsenic carcinogenesis. Previous studies have shown that gestational arsenic exposure of C3H mice, which tend to spontaneously develop liver tumors, increases the incidence of tumors in male offspring. In this study we used the same experimental protocol as in those previous studies and searched for DNA regions where methylation status was specifically altered in the liver tumors of arsenic-exposed offspring by using methylated DNA immunoprecipitation-CpG island microarrays. The methylation levels of the DNA regions selected were measured by quantitative methylation-specific PCR and bisulfite sequencing. The results of this study clarified a number of regions where DNA methylation status was altered in the liver tumors in the C3H mice compared to normal liver tissues. Among such regions, we showed that a gene body region of the oncogene Fosb underwent alteration in DNA methylation by gestational arsenic exposure. We also showed that Fosb expression significantly increased corresponding to the DNA methylation level of the gene body in the arsenic-exposed group. These findings suggest that the DNA methylation status can be used to identify tumors increased by gestational arsenic exposure.
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Affiliation(s)
- Takehiro Suzuki
- Center for Environmental Health Sciences, National Institute for Environmental Studies, Tsukuba, Japan
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15
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Maekawa F, Shimba S, Takumi S, Sano T, Suzuki T, Bao J, Ohwada M, Ehara T, Ogawa Y, Nohara K. Diurnal expression of Dnmt3b mRNA in mouse liver is regulated by feeding and hepatic clockwork. Epigenetics 2012; 7:1046-56. [PMID: 22847467 PMCID: PMC3515014 DOI: 10.4161/epi.21539] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
DNA methyltransferase 3B (DNMT3B) is critically involved in de novo DNA methylation and genomic stability, while the regulatory mechanism in liver is largely unknown. We previously reported that diurnal variation occurs in the mRNA expression of Dnmt3b in adult mouse liver. The aim of this study was to determine the mechanism underlying the diurnal expression pattern. The highest level and the lowest level of Dnmt3b mRNA expression were confirmed to occur at dawn and in the afternoon, respectively, and the expression pattern of Dnmt3b closely coincided with that of Bmal1. Since the diurnal pattern of Dnmt3b mRNA expression developed at weaning and scheduled feeding to separate the feeding cycle from the light/dark cycle led to a phase-shift in the expression, it could be assumed that feeding plays a critical role as an entrainment signal. In liver-specific Bmal1 knockout (L-Bmal1 KO) mice, L-Bmal1 deficiency resulted in significantly higher levels of Dnmt3b at all measured time points, and the time when the expression was the lowest in wild-type mice was shifted to earlier. Investigation of global DNA methylation revealed a temporal decrease of 5-methyl-cytosine percentage in the genome of wild-type mice in late afternoon. By contrast, no such decrease in 5-methyl-cytosine percentage was detected in L-Bmal1 KO mice, suggesting that altered Dnmt3b expression affects the DNA methylation state. Taken together, the results suggest that the feeding and hepatic clockwork generated by the clock genes, including Bmal1, regulate the diurnal variation in Dnmt3b mRNA expression and the consequent dynamic changes in global DNA methylation.
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Affiliation(s)
- Fumihiko Maekawa
- Center for Environmental Health Sciences; National Institute for Environmental Studies; Tsukuba, Japan
| | - Shigeki Shimba
- Department of Health Science; School of Pharmacy; Nihon University; Funabashi, Japan
| | - Shota Takumi
- Center for Environmental Health Sciences; National Institute for Environmental Studies; Tsukuba, Japan
| | - Tomoharu Sano
- Center for Environmental Measurement and Analysis; National Institute for Environmental Studies; Tsukuba, Japan
| | - Takehiro Suzuki
- Center for Environmental Health Sciences; National Institute for Environmental Studies; Tsukuba, Japan
| | - Jinhua Bao
- Center for Environmental Health Sciences; National Institute for Environmental Studies; Tsukuba, Japan
- Graduate School of Life and Environmental Sciences; University of Tsukuba; Tsukuba, Japan
| | - Mika Ohwada
- Center for Environmental Health Sciences; National Institute for Environmental Studies; Tsukuba, Japan
| | - Tatsuya Ehara
- Department of Molecular Endocrinology and Metabolism; Graduate School of Medical and Dental Sciences; Tokyo Medical and Dental University; Tokyo, Japan
| | - Yoshihiro Ogawa
- Department of Molecular Endocrinology and Metabolism; Graduate School of Medical and Dental Sciences; Tokyo Medical and Dental University; Tokyo, Japan
| | - Keiko Nohara
- Center for Environmental Health Sciences; National Institute for Environmental Studies; Tsukuba, Japan
- Graduate School of Life and Environmental Sciences; University of Tsukuba; Tsukuba, Japan
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Nohara K, Tateishi Y, Suzuki T, Okamura K, Murai H, Takumi S, Maekawa F, Nishimura N, Kobori M, Ito T. Late-onset Increases in Oxidative Stress and Other Tumorigenic Activities and Tumors With a Ha-ras Mutation in the Liver of Adult Male C3H Mice Gestationally Exposed to Arsenic. Toxicol Sci 2012; 129:293-304. [DOI: 10.1093/toxsci/kfs203] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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17
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Uchida M, Takumi S, Tachikawa K, Yamauchi R, Goto Y, Matsusaki H, Nakamura H, Kagami Y, Kusano T, Arizono K. Toxicity evaluation of glyphosate agrochemical components using Japanese medaka (Oryzias latipes) and DNA microarray gene expression analysis. J Toxicol Sci 2012; 37:245-54. [PMID: 22467014 DOI: 10.2131/jts.37.245] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
Using glyphosate agrochemical components, we investigated their acute toxicity to juvenile Japanese medaka (Oryzias latipes) as well as their toxic impact at gene expression level on the liver tissues of adult medaka using DNA microarray. In our acute toxicity test, juvenile medaka were exposed for 96 hr to each of the following glyphosate agrochemical components: 10~160 mg/l of glyphosate, 1.25~20 mg/l of fatty acid alkanolamide surfactant (DA), and 12~416 mg/l of a fully formulated glyphosate herbicide. As a result, LC(50) values of glyphosate, DA, and the glyphosate herbicide were > 160 mg/l, 8.5 mg/l, and 76.8 mg/l, respectively. On the other hand, adult male medaka fish were exposed to each of the glyphosate agrochemical components for 48 hr at the following concentrations: 16 mg/l of glyphosate, 0.5 mg/l of DA, and 16 mg/l-glyphosate/0.5 mg/l-DA mixture. Interestingly, DNA microarray analysis revealed that there were no significant gene expression changes in the medaka liver after exposure to glyphosate. Nevertheless, 78 and 138 genes were significantly induced by DA and the glyphosate/DA mixture, respectively. Furthermore, we identified five common genes that were affected by DA and glyphosate/DA mixture. These results suggested that glyphosate itself possessed very low toxicity as previously reported by some researchers at least to the small laboratory fish, and the major toxicity of the glyphosate agrochemical resided mainly in DA and perhaps in unintentionally generated byproduct(s) of glyphosate-DA mixture.
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Affiliation(s)
- Masaya Uchida
- Graduate School of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kunmamoto, Japan.
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Miyahara E, Nishie M, Takumi S, Miyanohara H, Nishi J, Yoshiie K, Oda H, Takeuchi M, Komatsu M, Aoyama K, Horiuchi M, Takeuchi T. Environmental mutagens may be implicated in the emergence of drug-resistant microorganisms. FEMS Microbiol Lett 2011; 317:109-16. [DOI: 10.1111/j.1574-6968.2011.02215.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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19
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Takumi S, Komatsu M, Furukawa T, Ikeda R, Sumizawa T, Akenaga H, Maeda Y, Aoyama K, Arizono K, Ando S, Takeuchi T. p53 Plays an important role in cell fate determination after exposure to microcystin-LR. Environ Health Perspect 2010; 118:1292-8. [PMID: 20421190 PMCID: PMC2944092 DOI: 10.1289/ehp.1001899] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2010] [Accepted: 04/26/2010] [Indexed: 05/03/2023]
Abstract
BACKGROUND Microcystin-LR, a cyclic heptapeptide, possesses the ability to inhibit the serine/threonine protein phosphatases PP1 and PP2A and, consequently, exhibits acute hepatocytotoxicity. Moreover, microcystin-LR induces cellular proliferation, resulting in tumor-promoting activity in hepatocytes. However, mechanisms that regulate the balance between cell death and proliferation after microcystin-LR treatment remain unclear. OBJECTIVE We examined the contribution of the transcription factor p53, as well as that of the hepatic uptake transporter for microcystin-LR, organic anion transporting polypeptide 1B3 (OATP1B3), to the cellular response to microcystin-LR exposure. METHODS We analyzed intracellular signaling responses to microcystin-LR by immunoblotting and real-time reverse-transcriptase polymerase chain reaction techniques using HEK293 human embryonic kidney cells stably transfected with SLCO1B3 (HEK293-OATP1B3). In addition, we analyzed the effect of attenuation of p53 function, via the p53 inhibitor pifithrin-alpha, and knockdown of p53 mRNA on the cytotoxicity of microcystin-LR using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. RESULTS Microcystin-LR induced the phosphorylation and accumulation of p53 in HEK293-OATP1B3 cells, which resulted in up-regulation of the expression of p53 transcript targets, including p21 and seven in absentia homolog 1 (siah-1). In addition, microcystin-LR activated Akt signaling through the phosphorylation of Akt and glycogen synthase kinase 3beta. Although Akt signaling was activated, the accumulation of p53 led cells to apoptosis after treatment with 50 nM microcystin-LR for 24 hr. Both pharmacological inhibition of transcription factor activity of p53 by pifithrin-alpha and knockdown of p53 with small hairpin RNA attenuated the susceptibility of HEK293-OATP1B3 cells to microcystin-LR. CONCLUSIONS This study demonstrates the importance of p53 in the regulation of cell fate after exposure to microcystin-LR. Our results suggest that, under conditions of p53 inactivation (including p53 mutation), chronic exposure to low doses of microcystin-LR may lead to cell proliferation through activation of Akt signaling. Results of this study may contribute to the development of chemoprevention and chemotherapeutic approaches to microcystin-LR poisoning.
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Affiliation(s)
- Shota Takumi
- Department of Environmental Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
- Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Japan
| | - Masaharu Komatsu
- Department of Environmental Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
- Department of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima, Japan
- Address correspondence to M. Komatsu, Department of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, 890-0056 Kagoshima, Japan. Telephone: 81-99-286-4200. Fax: 81-99-286-4200. E-mail:
| | | | - Ryuji Ikeda
- Department of Clinical Pharmacy and Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Tomoyuki Sumizawa
- Department of Environmental Toxicology, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Hitomi Akenaga
- Department of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima, Japan
| | - Yuta Maeda
- Department of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima, Japan
| | - Kohji Aoyama
- Department of Environmental Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
| | - Koji Arizono
- Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, Kumamoto, Japan
| | - Seiichi Ando
- Department of Food and Chemical Biology, Faculty of Fisheries, Kagoshima University, Kagoshima, Japan
| | - Toru Takeuchi
- Department of Environmental Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan
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Takumi S, Kimura H, Matsusaki H, Kawazoe S, Tominaga N, Arizono K. DNA microarray analysis of genomic responses of yeast Saccharomyces cerevisiae to nickel chloride. J Toxicol Sci 2010; 35:125-9. [DOI: 10.2131/jts.35.125] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Shota Takumi
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto
| | - Hirokazu Kimura
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto
| | - Hiromi Matsusaki
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto
| | - Sadahiro Kawazoe
- Department of Food Sciences and Nutritional Health, Kyoto Prefectural University
| | - Nobuaki Tominaga
- Department of Chemical and Biological Engineering, Ariake National College of Technology
| | - Koji Arizono
- Faculty of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto
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Takumi S, Komatsu M, Aoyama K, Watanabe K, Takeuchi T. Oxygen induces mutation in a strict anaerobe, Prevotella melaninogenica. Free Radic Biol Med 2008; 44:1857-62. [PMID: 18343236 DOI: 10.1016/j.freeradbiomed.2008.02.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2007] [Revised: 01/09/2008] [Accepted: 02/09/2008] [Indexed: 11/20/2022]
Abstract
Strict anaerobes are highly sensitive to oxygen, but the mutagenicity of oxygen in strict anaerobes has not been well understood. Prevotella melaninogenica, a strict anaerobe, is susceptible to oxygen and shows an increase in oxidative DNA damage upon exposure to oxygen. In this study, we have investigated the mutagenicity of oxygen and the types of mutations induced by oxygen. Exposure to oxygen decreased cell survival and increased the levels of 8-oxo-deoxyguanosine (8-oxodG). The frequency of rifampicin-resistant mutants was markedly increased after exposure to oxygen. After sequencing a 254-bp fragment of the rpoB gene, which encodes the beta subunit of bacterial RNA polymerase, a target molecule of rifampicin, we found that most mutants induced by oxygen had GC to TA transversions, a signature of 8-oxodG. In addition, all detected single-nucleotide changes would lead to amino acid changes that confer rifampicin resistance. These results indicate that oxygen is mutagenic in a strict anaerobe, P. melaninogenica, and its mutagenic characteristics could be analyzed with this experimental system.
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Affiliation(s)
- Shota Takumi
- Department of Environmental Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, 890-8544 Kagoshima, Japan
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Komatsu M, Furukawa T, Ikeda R, Takumi S, Nong Q, Aoyama K, Akiyama SI, Keppler D, Takeuchi T. Involvement of mitogen-activated protein kinase signaling pathways in microcystin-LR-induced apoptosis after its selective uptake mediated by OATP1B1 and OATP1B3. Toxicol Sci 2007; 97:407-16. [PMID: 17369605 DOI: 10.1093/toxsci/kfm054] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The serine/threonine protein phosphatase (PP) 2A inhibitor, microcystin-LR, selectively induces liver damage and promotes hepatocarcinogenesis. It is thought that microcystin-LR affects hepatocellular viability mainly through inhibition of PP2A, partially through PP1, and, in addition, by generation of reactive oxygen species (ROS). However, the molecular basis of the selective liver damage and the balance between cell death and survival remained unclear. We analyzed the cytotoxicity of low doses of microcystin-LR using HEK293 cells stably expressing the human hepatocyte uptake transporters, organic anion transporting polypeptide (OATP)1B1 (HEK293-OATP1B1 cells) and OATP1B3 (HEK293-OATP1B3 cells). HEK293-OATP1B1 (IC(50) 6.6nM) and HEK293-OATP1B3 cells (IC(50) 6.5nM) were equally very sensitive to microcystin-LR. In contrast, control-vector-transfected (HEK293-CV) cells were resistant to microcystin-LR. Using HEK293-OATP1B3 cells, the cytotoxicity was attenuated by substrates and inhibitors of OATP1B3, including bromosulfophthalein, rifampicin, and cyclosporin A. Microcystin-LR was transported into HEK293-OATP1B3 cells with 1.2 microM Km value, and its uptake was inhibited by above substances. Accumulation of microcystin-LR in the HEK293-OATP1B1 and HEK293-OATP1B3 cells was increased in a dose-dependent manner but not in HEK293-CV cells. Cellular serine/threonine PP activity of HEK293-OATP1B3 cells was decreased by microcystin-LR but not in HEK293-CV cells. Apoptotic changes were observed after incubation of the HEK293-OATP1B3 cells with microcystin-LR. We found by FACS analysis that microcystin-LR induced apoptosis but not necrosis in HEK293-OATP1B3 cells. Microcystin-LR activated several mitogen-activated protein kinases (MAPKs) including ERK1/2, JNK, and p38 through inhibition of PP2A. In addition, the cytotoxicity of microcystin-LR was attenuated by the inhibitors of MAPK pathways, including U0126, SP600125, and SB203580. The ROS scavenger N-acetyl-L-cysteine partially attenuated the cytotoxicity of microcystin-LR. Thus, the present study demonstrates that microcystin-LR induces apoptosis through activation of multiple MAPK pathways subsequent to its selective uptake via OATP1B1 and OATP1B3 and followed by inhibition of PP2A, in addition to the ROS generation which might contribute to apoptosis.
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Affiliation(s)
- Masaharu Komatsu
- Department of Environmental Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
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Abumhadi N, Kamenarova K, Todorovska E, Dimov G, Takumi S, Nakamura C, Anzai H, Atanassov A. Development of the Simple Gene Gun Apparatuses Systems. BIOTECHNOL BIOTEC EQ 2005. [DOI: 10.1080/13102818.2005.10817197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Abumhadi N, Kamenarova K, Todorovska E, Stoyanova M, Dimov G, Trifonova A, Takumi S, Nakamura C, Anzai H, Gecheff K, Atanassov A. Biotechnological Approaches for Cereal Crops Improvement. BIOTECHNOL BIOTEC EQ 2005. [DOI: 10.1080/13102818.2005.10817288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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25
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Hashimoto Z, Mori N, Kawamura M, Ishii T, Yoshida S, Ikegami M, Takumi S, Nakamura C. Genetic diversity and phylogeny of Japanese sake-brewing rice as revealed by AFLP and nuclear and chloroplast SSR markers. Theor Appl Genet 2004; 109:1586-96. [PMID: 15375619 DOI: 10.1007/s00122-004-1794-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2003] [Accepted: 08/06/2004] [Indexed: 05/05/2023]
Abstract
Japanese rice ( Oryza sativa L.) cultivars that are strictly used for the brewing of sake (Japanese rice wine) represent a unique and traditional group. These cultivars are characterized by common traits such as large grain size with low protein content and a large, central white-core structure. To understand the genetic diversity and phylogenetic characteristics of sake-brewing rice, we performed amplified fragment length polymorphism and simple sequence repeat analyses, using 95 cultivars of local and modern sake-brewing rice together with 76 cultivars of local and modern cooking rice. Our analysis of both nuclear and chloroplast genome polymorphisms showed that the genetic diversity in sake-brewing rice cultivars was much smaller than the diversity found in cooking rice cultivars. Interestingly, the genetic diversity within the modern sake-brewing cultivars was about twofold higher than the diversity within the local sake-brewing cultivars, which was in contrast to the cooking cultivars. This is most likely due to introgression of the modern cooking cultivars into the modern sake-brewing cultivars through breeding practices. Cluster analysis and chloroplast haplotype analysis suggested that the local sake-brewing cultivars originated monophyletically in the western regions of Japan. Analysis of variance tests showed that several markers were significantly associated with sake-brewing traits, particularly with the large white-core structure.
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Affiliation(s)
- Z Hashimoto
- Laboratory of Plant Genetics, Department of Biological and Environmental Science, Faculty of Agriculture, and Graduate School of Science and Technology, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, 657-8501, Japan
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Takumi S, Koike A, Nakata M, Kume S, Ohno R, Nakamura C. Cold-specific and light-stimulated expression of a wheat (Triticum aestivum L.) Cor gene Wcor15 encoding a chloroplast-targeted protein. J Exp Bot 2003; 54:2265-2274. [PMID: 12909691 DOI: 10.1093/jxb/erg247] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Wcor15, a member of the wheat cold-responsive (Cor) gene family, has been isolated and characterized. The deduced polypeptide WCOR15 (MW=14.7 kDa) showed high homology to the previously identified wheat and barley COR proteins. Southern blot analysis using diploid, tetraploid and hexaploid wheat and diploid Aegilops species showed that the wheat and related wild genomes possessed multiple copies of Wcor15 homologues. Five copies were assigned to the homologous group 2 chromosomes by nulli-tetrasomic analysis. Northern blot analysis showed that expression of Wcor15 was specifically induced by low-temperature. Homologous transcripts accumulated in leaves, and light markedly increased their steady-state levels. Bombardment-mediated transient expression analysis of a chimeric CaMV 35S::Wcor15-GFP construct showed protein-targeting to epidermal guard cell chloroplasts in excised spiderwort leaves. A promoter of Wcor15 contained at least three CRT/DRE-like sequence motifs found in Arabidopsis Cor genes and induced the reporter GUS gene expression in leaves of transgenic tobacco plants under low-temperature and light conditions. These results suggest that the functional Cor gene system involving the CRT/DRE cis-element is conserved in both monocotyledonous and dicotyledonous plants.
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MESH Headings
- Amino Acid Sequence
- Chloroplasts/metabolism
- Cloning, Molecular
- Cold Temperature
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- DNA, Plant/chemistry
- DNA, Plant/genetics
- Dehydration
- Gene Expression Regulation, Plant/drug effects
- Gene Expression Regulation, Plant/radiation effects
- Heat-Shock Proteins/genetics
- Heat-Shock Proteins/metabolism
- Light
- Molecular Sequence Data
- Plant Growth Regulators/pharmacology
- Plant Leaves/genetics
- Plant Leaves/metabolism
- Plant Proteins/genetics
- Plant Proteins/metabolism
- Plants, Genetically Modified
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Triticum/genetics
- Triticum/metabolism
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Affiliation(s)
- S Takumi
- Laboratory of Plant Genetics, Department of Biological and Environmental Science, Faculty of Agriculture and Graduate School of Science and Technology, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
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Ogihara Y, Isono K, Kojima T, Endo A, Hanaoka M, Shiina T, Terachi T, Utsugi S, Murata M, Mori N, Takumi S, Ikeo K, Gojobori T, Murai R, Murai K, Matsuoka Y, Ohnishi Y, Tajiri H, Tsunewaki K. Structural features of a wheat plastome as revealed by complete sequencing of chloroplast DNA. Mol Genet Genomics 2002; 266:740-6. [PMID: 11810247 DOI: 10.1007/s00438-001-0606-9] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2001] [Accepted: 10/15/2001] [Indexed: 10/27/2022]
Abstract
Structural features of the wheat plastome were clarified by comparison of the complete sequence of wheat chloroplast DNA with those of rice and maize chloroplast genomes. The wheat plastome consists of a 134,545-bp circular molecule with 20,703-bp inverted repeats and the same gene content as the rice and maize plastomes. However, some structural divergence was found even in the coding regions of genes. These alterations are due to illegitimate recombination between two short direct repeats and/or replication slippage. Overall comparison of chloroplast DNAs among the three cereals indicated the presence of some hot-spot regions for length mutations. Whereas the region with clustered tRNA genes and that downstream of rbcL showed divergence in a species-specific manner, the deletion patterns of ORFs in the inverted-repeat regions and the borders between the inverted repeats and the small single-copy region support the notion that wheat and rice are related more closely to each other than to maize.
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Affiliation(s)
- Y Ogihara
- Kihara Institute for Biological Research and Graduate School of Integrated Science, Yokohama City University, Yokohama 244-0813, Japan.
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Ohno R, Takumi S, Nakamura C. Expression of a cold-responsive Lt-Cor gene and development of freezing tolerance during cold acclimation in wheat (Triticum aestivum L.). J Exp Bot 2001; 52:2367-2374. [PMID: 11709586 DOI: 10.1093/jexbot/52.365.2367] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Time-courses of the development of freezing tolerance and the expression of a cold-responsive gene wlt10 were monitored during cold acclimation in wheat (Triticum aestivum L.). Bioassay showed that cold acclimation conferred much higher freezing tolerance on a winter cultivar than a spring cultivar. Northern blot analysis showed that the expression of wlt10 encoding a novel wheat member of a cereal-specific LT-COR protein family was specifically induced by low temperature. A freezing-tolerant winter cultivar accumulated the mRNA more rapidly and for a longer period than a susceptible spring cultivar. The increase in the amount of mRNA was temporary but the peak occurred at the time when the maximum level of freezing tolerance was attained. The mRNA accumulated more in the leaves than in the roots, and different light/dark regimes modulated the level of mRNA accumulation. Genomic Southern blot analyses using the nulli-tetrasomic series showed that the wlt10 homologues were located on the homologous group 2 chromosomes.
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Affiliation(s)
- R Ohno
- Laboratory of Plant Genetics, Department of Biological and Environmental Science, Faculty of Agriculture, Kobe University, 1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
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Tsukamoto N, Asakura N, Hattori N, Takumi S, Mori N, Nakamura C. Identification of paternal mitochondrial DNA sequences in the nucleus-cytoplasm hybrids of tetraploid and hexaploid wheat with D and D2 plasmons from Aegilops species. Curr Genet 2000; 38:208-17. [PMID: 11126780 DOI: 10.1007/s002940000153] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mitochondrial (mt) DNA structures were studied in 12 nucleus-cytoplasm (NC) hybrids of tetraploid and hexaploid wheat in which nuclear genomes of the recurrent paternal wheat parents were combined with D and D2 plasmons from Aegilops species. RFLP analysis of 15 mtDNA regions indicated the presence of the paternal sequences in six regions encompassing 11 structural genes in all the NC hybrids. PCR-RFLP analysis showed that one region (a nad3-orf156 region) consisted of a mixture of the maternal, paternal and novel paternal-like sequences. The presence of unexpectedly high levels of the paternal sequences was confirmed by random PCR cloning and sequencing of this region. PCR-RFLP analysis of the random clones further showed that the relative stoichiometry of the maternal and paternal sequences varied depending on the plasmons from the maternal parents and the nuclear backgrounds of the paternal parents. Our results suggest that the differential amplification of the paternal mtDNA sequences is under the control of NC interaction in these NC hybrids.
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Affiliation(s)
- N Tsukamoto
- Department of Biological and Environmental Science, Faculty of Agriculture, Graduate School of Science and Technology, Kobe University, Japan
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Tsuda K, Tsvetanov S, Takumi S, Mori N, Atanassov A, Nakamura C. New members of a cold-responsive group-3 Lea/Rab-related Cor gene family from common wheat (Triticum aestivum L.). Genes Genet Syst 2000; 75:179-88. [PMID: 11126566 DOI: 10.1266/ggs.75.179] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
A Cor (cold-responsive) cDNA that belongs to the group-3 Lea (late embryogenesis abundant)/Rab (responsive to abscisic acid, ABA) family was isolated from a winter-hardy cultivar of common wheat (Triticum aestivum L.). Screening of a cold-acclimated cDNA library was performed using an ABA- and other stress-responsive barley cDNA clone, Hva1, as a probe. A wheat cDNA clone (designated as Wrab19) putatively encoded a basic (pI = 10.3) and hydrophobic protein with 179 amino acids. The deduced protein showed characteristics of the group-3 LEA/RAB protein family. In contrast to the single copy barley Hva1, Wrab19 belonged to a multigene family in the hexaploid wheat genome and six loci were assigned to the homoeologous group 1 chromosomes. Using Wrab19 as a probe, four homologous cDNAs (designated as Wrab17) were isolated that encoded acidic (pI = 4.6-4.7) and hydrophobic proteins, all with 166 amino acids. The deduced proteins showed high homology (a mean of 84% identity) with a barley gibberellic acid (GA3)-inducible protein, ES2A, and several other group-3 LEA/RAB proteins. Wrab17 was considered to be a three-copy gene and each copy was assigned to chromosome 5A, 4B or 4D of hexaploid wheat. Transcripts of both Wrab19 and Wrab17 accumulated within 1 day of cold acclimation at 4 degrees C. They were responsive to ABA and/or GA3, but showed some cultivar differences in their response to these plant hormones. We conclude that the two genes are new members of the group-3 Lea/Rab-related Cor gene family in wheat.
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Affiliation(s)
- K Tsuda
- Laboratory of Plant Genetics, Department of Biological and Environmental Science, Graduate School of Science & Technology, Kobe University, Kobe 657-8501, Japan
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Ando S, Takumi S, Ueda Y, Ueda T, Mori N, Nakamura C. Nicotiana tabacum cDNAs encoding alpha and beta subunits of a heterotrimeric GTP-binding protein isolated from hairy root tissues. Genes Genet Syst 2000; 75:211-21. [PMID: 11126570 DOI: 10.1266/ggs.75.211] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Heterotrimeric GTP-binding proteins (G-proteins) play important roles in signal transduction pathways in eukaryotic cells. Through differential screening of a hairy root cDNA library of tobacco (Nicotiana tabacum L.) against transcripts from non-root tissues of normal cuttings, we obtained a partial cDNA clone that showed abundant expression and high homology to the alpha subunit gene of plant G-protein. After RACE-PCR, a full-length cDNA clone was obtained, which was 1,677-bp in length and contained an open reading frame encoding a protein of 384 amino acids. A cDNA clone encoding a beta subunit of G-protein was also isolated from the same cDNA library based on PCR amplification and library screening. The clone was 1,600-bp in length and contained an open reading frame encoding 377 amino acids. The deduced amino acid sequences of these clones showed high homology (75.5 to 99.8% amino acid identity) with alpha and beta subunits of other plant G-proteins. Genomic Southern blot analysis showed that the amphidiploid tobacco genome possessed two major copies of both alpha and beta subunit genes and some minor homologous copies. Northern blot analysis showed that the transcript of alpha subunit gene was abundant in the root tissues, particularly in the hairy root tissues. In contrast, the level of expression of the beta subunit gene was equivalent in all the tissues studied. Possible function of tobacco G-protein was discussed.
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Affiliation(s)
- S Ando
- Laboratory of Plant Genetics, Department of Biological and Environmental Science, Faculty of Agriculture, Graduate School of Science and Technology, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
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Takumi S, Kosugi T, Murai K, Mori N, Nakamura C. Molecular cloning of three homoeologous cDNAs encoding orthologs of the maize KNOTTED1 homeobox protein from young spikes of hexaploid wheat. Gene 2000; 249:171-81. [PMID: 10831851 DOI: 10.1016/s0378-1119(00)00164-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The plant knotted1 (kn1)-like homeobox genes are known to play important roles in the maintenance of shoot apical meristem (SAM), determination of cell fate and differentiation of vegetative tissues. To study structural diversity of the three homologous loci encoding a KN1-like homeobox protein in the hexaploid wheat genome, we isolated clones from a cDNA library of young spikes of Japanese common wheat cultivar 'Norin 26'. Three different but highly homologous cDNAs were isolated and their sequences were determined. The mean homology of the deduced amino acid sequences was 96% as compared to the barley ortholog KNOX3. The wheat kn1-like homeobox proteins named WKNOX1 are encoded by a single set of homologous genes on the homologous group 4 chromosomes in the three component genomes of common wheat, i.e. 4A, 4B and 4D. The nucleotide sequence data and the Southern blot pattern suggested that the three homologous loci of wknox1 genes are highly conserved through polyploid evolution of wheat. They were expressed in SAM-containing shoots and young spikes but not in developed leaves, glumes and lemmas and callus tissues. The ectopic expression of the wknox1 was observed in lemma of wheat Hooded (Hd) mutants. The result suggested that the Hd gene is a dominant allele of the wknox1 locus on chromosome 4A.
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MESH Headings
- Amino Acid Sequence
- Base Sequence
- Blotting, Southern
- Chromosome Mapping
- Cloning, Molecular
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- DNA, Complementary/isolation & purification
- DNA, Plant/genetics
- Exons
- Gene Expression Profiling
- Genes, Homeobox/genetics
- Genes, Plant/genetics
- Homeodomain Proteins/genetics
- Introns
- Molecular Sequence Data
- Mutation
- Phylogeny
- Plant Proteins
- Polymerase Chain Reaction
- Polymorphism, Genetic
- Polyploidy
- Protein Isoforms/genetics
- RNA, Plant/genetics
- RNA, Plant/metabolism
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Sequence Homology, Nucleic Acid
- Tissue Distribution
- Triticum/genetics
- Zea mays/genetics
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Affiliation(s)
- S Takumi
- Department of Biological and Environmental Science, Kobe University, Nada-ku, Japan.
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Abstract
A method using particle bombardment and beta-glucuronidase (GUS) assay was applied to rice callus for detecting the excision of the maize Ds element trans-activated by the Ac transposase source. Excision of Ds biolistically introduced into rice callus resulted in the restoration of the interrupted gus gene expression, allowing visual detection of trans-activation two days after bombardment. Only the transgenic callus lines expressing the Ac transposase gene and the wild-type callus co-transformed with Ac and Ds revealed GUS activity. Frequency of excision, estimated based on the relative GUS activity, ranged from 0.3% to 2.2%. Callus lines showing different levels of Ac transcripts revealed varying excision frequencies. At the later stages of callus growth after selection for the Ac/Ds transformed lines, excision events were detected by GUS assay and confirmed by PCR and sequence analyses of the excision sites in individual colonies. GUS activity was also demonstrated in the primary regenerants from the Ac/Ds-transformed callus colonies. The method described in this study may be used as an approach for rapid detection of excision events and assessment of various factors limiting Ac/Ds activity in rice cells.
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MESH Headings
- Biolistics
- Cells, Cultured
- DNA Transposable Elements/genetics
- DNA, Plant/genetics
- DNA, Plant/metabolism
- DNA, Recombinant/genetics
- DNA, Recombinant/metabolism
- Gene Expression Regulation, Plant
- Genes, Reporter
- Genes, Synthetic
- Glucuronidase/biosynthesis
- Glucuronidase/genetics
- Oryza/genetics
- Plant Proteins/metabolism
- Plants, Genetically Modified
- Recombinant Fusion Proteins/metabolism
- Repetitive Sequences, Nucleic Acid
- Sequence Alignment
- Sequence Homology, Nucleic Acid
- Transcriptional Activation
- Transposases/metabolism
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Affiliation(s)
- R Solis
- Graduate School of Science and Technology, Faculty of Agriculture, Kobe University, Japan
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Tsvetanov S, Ohno R, Tsuda K, Takumi S, Mori N, Atanassov A, Nakamura C. A cold-responsive wheat (Triticum aestivum L.) gene wcor14 identified in a winter-hardy cultivar 'Mironovska 808'. Genes Genet Syst 2000; 75:49-57. [PMID: 10846621 DOI: 10.1266/ggs.75.49] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
A cDNA library was constructed from a cold-acclimated winter-hardy common wheat (Triticum aestivum L.) cultivar 'Mironovska 808'. Using this library and a cold- and light-responsive barley cDNA clone cor14b as a probe, cDNAs of a homologous wheat gene wcor14 were isolated. Two identical cDNAs designated as wcor14a had an open reading frame encoding an acidic (pI = 4.71) and hydrophobic polypeptide with 140 amino acids (MW = 13.5 kDa). The deduced WCOR14a polypeptide showed 70% identity with the barley chloroplast-imported COR14b and had a nearly identical N-terminal, putative chloroplast transit peptide of 51 amino acid residues. Another cDNA clone wcor14b was assumed to encode a polypeptide WCORb which had 5 substitutions and a frame shift in the C-terminal region as compared with WCOR14a. RACE PCR, genomic PCR and Southern blot analyses suggested that wcor14 and its related sequences constitute a small multigene family with and without an intron in the hexaploid wheat genome. Northern blot analysis showed that transcripts of wcor14 accumulated within 3-6 hours of cold acclimation at 4 degrees C and the level reached a maximum at day 3. The transcripts became non-detectable within 3 hours after de-acclimation at room temperature. Contrary to the barley cor14b, a similar level of wcor14 transcripts was detected under the continuous darkness. Neither treatment with NaCl, ABA nor dehydration induced its expression. Based on these results we conclude that wcor14 is a wheat orthologue of the barley cor14b and specifically induced by low temperature.
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Affiliation(s)
- S Tsvetanov
- Department of Life Science, Graduate School of Science & Technology, Kobe University, Japan
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Takumi S, Murai K, Mori N, Nakamura C. Variations in the maize Ac transposase transcript level and the Ds excision frequency in transgenic wheat callus lines. Genome 1999; 42:1234-41. [PMID: 10659792 DOI: 10.1139/g99-077] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To investigate the excision of a maize transposable element in wheat cells, plasmid DNAs containing a Dissociation (Ds) element located between a rice actin 1 gene promoter and a beta-glucuronidase (GUS) gene (gus) were introduced into wheat callus lines by microprojectile bombardment, and transient GUS expression was assayed. The gus-expressing cells after Ds excision were detected only when the Activator (Ac) transposase gene was co-transformed. To further examine a relationship between the amount of Ac mRNA and the Ds excision frequency, the Ds-containing plasmids were introduced into 15 independent transgenic callus lines transformed with the Ac transposase gene. Ten lines expressed the Ac transposase gene under the control of either the cauliflower mosaic virus 35S promoter or the Ac native promoter. The gus gene expression that indicated the Ds excision was observed only in the transgenic callus lines stably expressing the Ac transposase gene. The number of blue spots reflecting the frequency of Ds excision was variable among them. Northern-blot analysis also showed a large variability in the amount of Ac transposase transcripts among the lines. It was however noted that the excision frequency was decreased at a high level of the Ac transposase transcripts, supporting the hypothesis that Ds excision is inhibited above a certain level of the Ac transposase as observed in maize and transgenic tobacco.
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Affiliation(s)
- S Takumi
- Department of Biological and Environmental Science, Faculty of Agriculture, Kobe University, Japan.
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Makino A, Shimada T, Takumi S, Kaneko K, Matsuoka M, Shimamoto K, Nakano H, Miyao-Tokutomi M, Mae T, Yamamoto N. Does Decrease in Ribulose-1,5-Bisphosphate Carboxylase by Antisense RbcS Lead to a Higher N-Use Efficiency of Photosynthesis under Conditions of Saturating CO2 and Light in Rice Plants? Plant Physiol 1997; 114:483-491. [PMID: 12223722 PMCID: PMC158328 DOI: 10.1104/pp.114.2.483] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Rice (Oryza sativa L.) plants with decreased ribulose-1,5-bisphosphate carboxylase (Rubisco) were obtained by transformation with the rice rbcS antisense gene under the control of the rice rbcS promoter. The primary transformants were screened for the Rubisco to leaf N ratio, and the transformant with 65% wild-type Rubisco was selected as a plant set with optimal Rubisco content at saturating CO2 partial pressures for photosynthesis under conditions of high irradiance and 25[deg]C. This optimal Rubisco content was estimated from the amounts and kinetic constants of Rubisco and the gas-exchange data. The R1 selfed progeny of the selected transformant were grown hydroponically with different N concentrations. Rubisco content in the R1 population was distributed into two groups: 56 plants had about 65% wild-type Rubisco, whereas 23 plants were very similar to the wild type. Although the plants with decreased Rubisco showed 20% lower rates of light-saturated photosynthesis in normal air (36 Pa CO2), they had 5 to 15% higher rates of photosynthesis in elevated partial pressures of CO2, (100-115 Pa CO2) than the wild-type plants for a given leaf N content. We conclude that the rice plants with 65% wild-type Rubisco show a higher N-use efficiency of photosynthesis under conditions of saturating CO2 and high irradiance.
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Affiliation(s)
- A. Makino
- Department of Applied Biological Chemistry, Faculty of Agriculture, Tohoku University, Tsutsumidori-Amamiyamachi, Sendai 981, Japan (A.M., K.K., H.N., T.M.)
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Takumi S, Shimada T. Variation in transformation frequencies among six common wheat cultivars through particle bombardment of scutellar tissues. Genes Genet Syst 1997; 72:63-9. [PMID: 9265734 DOI: 10.1266/ggs.72.63] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The transformation technique in common wheat has already been established by using microprojectile bombardment and scutellar tissues of immature embryos. In this study, in vitro culture response of immature embryos and the production of transgenic wheat plants were examined in six common wheat cultivars, i.e., Chinese Spring, Akadaruma, Haruhikari, Shiroganekomugi, Norin 12, and Norin 61. In all genotypes, more than seven hundred immature embryos were bombarded with a plasmid containing a bialaphos-resistant gene under control of the rice actin 1 gene. (Act1) promoter. Although the transient expression of the reporter gene encoding beta-glucuronidase following the rice Act1 promoter was similar in five of the six cultivars tested, the frequency of stable transformation varied with the genotype. The frequency of transformation was the highest in Akadaruma and Norin 12 of the six wheat cultivars; independently transformed plants were produced from 1.4% and 1.7% of bombarded embryos, respectively. On the other hand, the immature embryos of Norin 61 and Shiroganekomugi showing low efficiency of in vitro culture generated no transgenic plants. This variation of the transformation frequency was generally caused by the difference in the in vitro culture response with the genotype, rather than the efficiency of the introduction of the transgene into wheat cells by particle bombardment.
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Affiliation(s)
- S Takumi
- Research Institute of Agricultural Resources, Ishikawa Agricultural College, Japan
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38
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Takumi S. Hygromycin-resistant calli generated by activation and excision of maize Ac/Ds transposable elements in diploid and hexaploid wheat cultured cell lines. Genome 1996; 39:1169-75. [PMID: 8983186 DOI: 10.1139/g96-147] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
To investigate the activation and transposition of maize transposable elements in wheat cultured cells, plasmid DNAs containing the maize Ac/Ds elements located between the CaMV 35S promoter and a hygromycin B resistance gene (hph) were introduced into two wheat (Triticum aestivum and Triticum monococcum) cultured cell lines by microprojectile bombardment. In the first experiment, hph was activated by excision of the Ac element, which encodes transposase, in the two wheat cell lines. In the second experiment, the Ds element was excised by a stabilized Ac element, lacking inverted repeats of the Ac element and located on another plasmid, and therefore leading to activation of hph. After selection of bombarded cells by hygromycin B, many resistant calli were recovered in both wheat cell lines. The integration of hph and the Ac transposase gene was confirmed by PCR and genomic Southern analysis. The stable expression of hph and the transposase gene was also assessed by Northern blot and reverse transcriptase PCR analysis, respectively. Moreover, characteristic sequence alterations were found at Ac/Ds excision sites. These findings indicate that the maize Ac/Ds transposable elements are activated and excised by expression of the Ac transposase gene in both diploid and hexaploid wheat cells.
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Affiliation(s)
- S Takumi
- Laboratory of Genetic Resources, Ishikawa Agricultural College, Japan
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