1997 年度実績報告書

低温適応と低温耐性の分子機構

研究課題

研究課題/領域番号	08102011
研究機関	岡崎国立共同研究機構
研究代表者	村田紀夫岡崎国立共同研究機構, 基礎生物学研究所, 教授 (90011569)
研究分担者	鈴木石根岡崎国立共同研究機構, 基礎生物学研究所, 助手 (10290909) 西山佳孝岡崎国立共同研究機構, 基礎生物学研究所, 助手 (30281588) 坂本敦岡崎国立共同研究機構, 基礎生物学研究所, 助手 (60270477)
キーワード	低温適応 / 低温耐性 / 不飽和化酵素 / 不飽和膜脂質 / ベタイン / 低温シグナル / 形質転換植物 / 光合成
研究概要	(1)低温と凍結に対する不飽和膜脂質の保護効果の研究:1価の不飽和脂肪酸しか生合成できないラン藻Synechococcusに新たな不飽和化酵素の遺伝子を導入し、膜脂質の不飽和結合数を増加させることに成功した。この遺伝子導入株および昨年度に作製したラン藻Synechocystisの不飽和化酵素の遺伝子破壊株の解析から、低温に対する不飽和膜脂質の保護効果の作用部位は,光化学系II複合体のD1タンパク質前駆体のC末端のプロセシングであることを明らかにした。 (2)低温と凍結に対するベタインの保護効果の研究:土壌細菌のコリンオキシダーゼ遺伝子をシロイヌナズナおよびイネに導入することでベタイン合成能を獲得した形質転換植物の作製に成功した。これらの形質転換植物では、塩、低温、高温、強光に対する耐性の増強がみられた。特にシロイヌナズナについては、種子の吸水時と発芽時における低温および高温に対する耐性が増強していることを明らかにした。 (3)新しい低温適応因子の研究:不飽和化酵素の遺伝子破壊により膜脂質の不飽和度が温度によって変化しなくなったラン藻Synechocystisの変異株を取得した。これを用いて新しい低温適応因子の単離に向けて予備実験を行った。 (4)低温センサーと低温シグナル伝達系の研究:ラン藻Synechocystisの4種の不飽和化酵素遺伝子が低温に対して異なった発現応答を示すことを明らかにした。低温刺激に対して最も重要なΔ9不飽和化酵素の遺伝子発現は構成的であったが、次に重要なΔ12不飽和化酵素の遺伝子は比較的ゆっくりと応答し、あまり重要でないΔ6とΔ15不飽和化酵素の各遺伝子が最も早く応答した。またラン藻Synechocystisを用いたランダムな遺伝子破壊およびセンサーキナーゼと推定される遺伝子群の破壊による低温シグナル伝達系に異常をきたした変異株を多数取得した。

研究成果
(19件)

すべてその他

すべて文献書誌 (19件)

[文献書誌] Deshnium, et al.: "The action in vivo of glycine betaine in enhancement of tolerance of Synechococcus sp.strain PCC 7942 to low temperature." Journal of Bacteriology. 179. 339-344 (1997)
[文献書誌] Gombos, et al.: "Genetic enhancement of the ability to tolerate photoinhibition by introduction of unsaturated bonds into membrane glycerolipids." Plant Physiology. 115. 551-559 (1997)
[文献書誌] Hayashi, et al.: "Transformation of Arabidopsis thaliana with the codA gene for choline oxidase ; accumulation of glycinebetaine and enhanced tolerance to salt and cold stress." Plant Journal. 12. 133-142 (1997)
[文献書誌] Hideg & Murata: "The irreversible photoinhibition of the photosystem II complex in leaves of Vicia faba under strong light." Plant Science. 130. 151-158 (1997)
[文献書誌] Kanervo, et al.: "Membranelipid unsaturation modulates processing of photosystem II reaction-center protein D1 at low temperature." Plant Physiology. 114. 841-849 (1997)
[文献書誌] Los, et al.: "Differences in the control of the temperature-dependent expression of four genes for desaturases in Synechocystis sp.PCC 6803." Molecular Microbiology. 25. 1167-1175 (1997)
[文献書誌] Nishiyama, et al.: "Thermal protection of the oxygen-evolving machinery by PsbU,an extrinsic protein of photosystem II,in Synechococcus species PCC 7002." Plant Physiology. 115. 1473-1480 (1997)
[文献書誌] Sakamoto, et al.: "Low-temperature induced desaturation of fatty acids and expression of desaturase genes in the cyanobacterium Synechococcus sp.PPC 7002." FEMS Microbiology Letters. 152. 313-320 (1997)
[文献書誌] Sato, et al.: "Identification of a cold-regulated RNA-binding protein from the marine cyanobacterium Synechococcus sp.PCC 7002." Jouranl of Plant Research. 110. 405-410 (1997)
[文献書誌] Tasaka & Murata: "Glycerol-3-phosphate acyltransferase in plants (review)." Biochimica et Biophysica Acta. 1348. 10-16 (1997)
[文献書誌] Los & Murata: "Membrane fluidity and temperature perception (review)." Plant Physiology. 115. 875-879 (1997)
[文献書誌] Fukuchi, et al.: "Characterization of Δ9 acyl-lipid desaturase homologues from Arabidopsis thaliana." Plant & Cell Physiolohy. 39. 247-253 (1998)
[文献書誌] Alia, et al.: "Transformation with a gene for choline oxidase enhances the cold tolerance of Arabidopsis during germination and early growth." Plant,Cell & Environment. (印刷中). (1998)
[文献書誌] Panpoom, et al.: "Biochemical characterization of a Δ12 acyl-lipid desaturase after overexpression of the enzyme in Escherichia coli." Biochimica et Biophysica Acta. (印刷中). (1998)
[文献書誌] Papageorrgiou, et al.: "A method to prove the cytoplasmic osmolarity and osmotic water and solute fluxes across the cell membrane of cyanobacteria with chlorophyll a fluorescence : Experiments with Synechococcus sp.PCC 7942." Physiologia Plantarum. (印刷中). (1998)
[文献書誌] Sippola, et al.: "Genetically engineered increase in fatty acid unsaturation in Synechococcus sp.PCC 7942 allows D1 protein from exchange and sustenance of photosystem II activity at low temperature." European Journal of Biochemistry. (印刷中). (1998)
[文献書誌] Sakamoto, et al.: "Metabolic engineering of rice leading to biosynthesis of glycinebetaine and tolerance to salt and cold." Plant Molecular Biology. (印刷中). (1998)
[文献書誌] Satoh & Murata (eds.): "Stress Responses of Photosynthetic Organisms. Molecular Mechanisms and Molecular Regulations" Elsevier Science (Amsterdam), 260 (1997)
[文献書誌] Siegenthalar & Murata (eds.): "Lipids in Photosynthesis" Kluwer Academic Publishers (Dordrecht) (印刷中), (1998)

1997 年度 実績報告書

低温適応と低温耐性の分子機構

研究代表者

村田 紀夫 岡崎国立共同研究機構, 基礎生物学研究所, 教授 (90011569)

研究成果

[文献書誌] Deshnium, et al.: "The action in vivo of glycine betaine in enhancement of tolerance of Synechococcus sp.strain PCC 7942 to low temperature." Journal of Bacteriology. 179. 339-344 (1997)

[文献書誌] Gombos, et al.: "Genetic enhancement of the ability to tolerate photoinhibition by introduction of unsaturated bonds into membrane glycerolipids." Plant Physiology. 115. 551-559 (1997)

[文献書誌] Hayashi, et al.: "Transformation of Arabidopsis thaliana with the codA gene for choline oxidase ; accumulation of glycinebetaine and enhanced tolerance to salt and cold stress." Plant Journal. 12. 133-142 (1997)

[文献書誌] Hideg & Murata: "The irreversible photoinhibition of the photosystem II complex in leaves of Vicia faba under strong light." Plant Science. 130. 151-158 (1997)

[文献書誌] Kanervo, et al.: "Membranelipid unsaturation modulates processing of photosystem II reaction-center protein D1 at low temperature." Plant Physiology. 114. 841-849 (1997)

[文献書誌] Los, et al.: "Differences in the control of the temperature-dependent expression of four genes for desaturases in Synechocystis sp.PCC 6803." Molecular Microbiology. 25. 1167-1175 (1997)

[文献書誌] Nishiyama, et al.: "Thermal protection of the oxygen-evolving machinery by PsbU,an extrinsic protein of photosystem II,in Synechococcus species PCC 7002." Plant Physiology. 115. 1473-1480 (1997)

[文献書誌] Sakamoto, et al.: "Low-temperature induced desaturation of fatty acids and expression of desaturase genes in the cyanobacterium Synechococcus sp.PPC 7002." FEMS Microbiology Letters. 152. 313-320 (1997)

[文献書誌] Sato, et al.: "Identification of a cold-regulated RNA-binding protein from the marine cyanobacterium Synechococcus sp.PCC 7002." Jouranl of Plant Research. 110. 405-410 (1997)

[文献書誌] Tasaka & Murata: "Glycerol-3-phosphate acyltransferase in plants (review)." Biochimica et Biophysica Acta. 1348. 10-16 (1997)

[文献書誌] Los & Murata: "Membrane fluidity and temperature perception (review)." Plant Physiology. 115. 875-879 (1997)

[文献書誌] Fukuchi, et al.: "Characterization of Δ9 acyl-lipid desaturase homologues from Arabidopsis thaliana." Plant & Cell Physiolohy. 39. 247-253 (1998)

[文献書誌] Alia, et al.: "Transformation with a gene for choline oxidase enhances the cold tolerance of Arabidopsis during germination and early growth." Plant,Cell & Environment. (印刷中). (1998)

[文献書誌] Panpoom, et al.: "Biochemical characterization of a Δ12 acyl-lipid desaturase after overexpression of the enzyme in Escherichia coli." Biochimica et Biophysica Acta. (印刷中). (1998)

[文献書誌] Papageorrgiou, et al.: "A method to prove the cytoplasmic osmolarity and osmotic water and solute fluxes across the cell membrane of cyanobacteria with chlorophyll a fluorescence : Experiments with Synechococcus sp.PCC 7942." Physiologia Plantarum. (印刷中). (1998)

[文献書誌] Sippola, et al.: "Genetically engineered increase in fatty acid unsaturation in Synechococcus sp.PCC 7942 allows D1 protein from exchange and sustenance of photosystem II activity at low temperature." European Journal of Biochemistry. (印刷中). (1998)

[文献書誌] Sakamoto, et al.: "Metabolic engineering of rice leading to biosynthesis of glycinebetaine and tolerance to salt and cold." Plant Molecular Biology. (印刷中). (1998)

[文献書誌] Satoh & Murata (eds.): "Stress Responses of Photosynthetic Organisms. Molecular Mechanisms and Molecular Regulations" Elsevier Science (Amsterdam), 260 (1997)

[文献書誌] Siegenthalar & Murata (eds.): "Lipids in Photosynthesis" Kluwer Academic Publishers (Dordrecht) (印刷中), (1998)

1997 年度実績報告書

村田紀夫岡崎国立共同研究機構, 基礎生物学研究所, 教授 (90011569)