A5012827102- Plant Stress Responses and Tolerance
- Photosynthetic Processes and Mechanisms
- Plant Molecular Biology Research
- Plant nutrient uptake and metabolism
- Light effects on plants
- Plant Micronutrient Interactions and Effects
- Lipid Membrane Structure and Behavior
- Seed Germination and Physiology
- Plant responses to water stress
- Plant Reproductive Biology
- Lipid metabolism and biosynthesis
- Legume Nitrogen Fixing Symbiosis
- Aluminum toxicity and tolerance in plants and animals
- Polysaccharides and Plant Cell Walls
- Plant tissue culture and regeneration
- Postharvest Quality and Shelf Life Management
- Magnetic and Electromagnetic Effects
- Mass Spectrometry Techniques and Applications
- Proteins in Food Systems
- Crystallization and Solubility Studies
- Plant Physiology and Cultivation Studies
- Freezing and Crystallization Processes
- Advanced Proteomics Techniques and Applications
- Ion Transport and Channel Regulation
- X-ray Diffraction in Crystallography
Iwate University
2016-2025
Institute of Biomedical Science
2020
Iwate Medical University
2020
Purdue University West Lafayette
2013
Infrafrontier
2009-2010
Graduate School USA
2007
Kumamoto University
1981-2005
Kumamoto Industrial Research Institute
1999-2005
Cornell University
1988-2003
Michigan State University
1996-1998
Plant aquaporins form a large protein family including plasma membrane-type (PIPs) and tonoplast-type (TIPs), facilitate osmotic water transport across membranes as key physiological function. We identified 33 genes for in the genome sequence of rice (Oryza sativa L. cv. Nipponbare). investigated their expression levels leaf blades, roots anthers (cv. Akitakomachi) using semi-quantitative reverse transcription–PCR (RT–PCR). At both early tillering (21 d after germination) panicle formation...
Maximum freezing tolerance of Arabidopsis thaliana L. Heyn (Columbia) was attained after 1 week cold acclimation at 2[deg]C. During this time, there were significant changes in both the lipid composition plasma membrane and freeze-induced lesions that associated with injury. The proportion phospholipids increased from 46.8 to 57.1 mol% total lipids little change proportions phospholipid classes. Although di-unsaturated species phosphatidylcholine phosphatidylethanolamine increased,...
Constitutive expression of the co ld- r egulated COR15a gene Arabidopsis thaliana results in a significant increase survival isolated protoplasts frozen over range −4.5 to −7°C. The increased freezing tolerance is result decreased incidence freeze-induced lamellar-to-hexagonal II phase transitions that occur regions where plasma membrane brought into close apposition with chloroplast envelope as dehydration. Moreover, mature polypeptide encoded by this gene, COR15am, increases transition...
Cold acclimation in plants is associated with the expression of COR (cold-regulated) genes that encode polypeptides unknown function. It has been widely speculated products these might have roles freezing tolerance. Here we provide direct evidence support this hypothesis. We show constitutive COR15a, a cold-regulated gene Arabidopsis thaliana encodes chloroplast-targeted polypeptide, enhances vivo tolerance chloroplasts nonacclimated by almost 2 degrees C, nearly one-third increase occurs...
Abstract To understand the mechanistic basis of cold temperature stress and role auxin response, we characterized root growth gravity response Arabidopsis thaliana after stress, finding that 8 to 12 h at 4°C inhibited by ∼50%. The auxin-signaling mutants axr1 tir1, which show a reduced responded treatment like wild type, suggesting affects transport rather than signaling. Consistently, expression analyses an auxin-responsive marker, IAA2-GUS, direct assay confirmed inhibits basipetal...
The lipid composition of the plasma membrane isolated from leaves spring oat (Avena sativa L. cv Ogle) was vastly different that winter rye (Secale cereale Puma). contained large proportions phospholipids (28.8 mol% total lipids), cerebrosides (27.2 mol%), and acylated sterylglucosides (27.3 mol%) with lesser free sterols (8.4 (5.6 mol%). In contrast, a greater proportion (36.6 there lower (16.4 mol%); (38.1 were predominant sterols, (2.9 Although relative individual phospholipids, primarily...
Summary Although enhancement of freezing tolerance in plants during cold acclimation is closely associated with an increase the cryostability plasma membrane, molecular mechanism for increased membrane still to be elucidated. In Arabidopsis, enhanced was detectable after at 2°C as short 1 day, and maximum attained week. To identify proteins that change quantity response acclimation, a highly purified fraction isolated from leaves before were separated gel electrophoresis. We found there...
The plasma membrane is considered to be the primary site of injury when plant cells are subjected extracellular freezing. In order for plants or acquire freezing tolerance, it is, thus, necessary that increases its cryostability during freeze-thaw excursion. During cold acclimation both under natural and artificial conditions, there compositional, structural functional changes occurring in membrane, many, if not all, which ultimately contribute increased stability conditions. addition,...
The lipid composition of plasma membranes and tonoplasts from etiolated mung bean hypocotyls was examined in detail. Phospholipids, sterols, ceramide monohexoside(s) were the major classes both membranes. content phospholipids on a protein basis higher tonoplast, but total sterols similar Accordingly, sterol to phospholipid molar ratio membrane than that tonoplast. Phosphatidylethanolamine phosphatidylcholine comprised Phosphatidylinositol, phosphatidylserine, phosphatidylglycerol identified...
Abstract Plant freezing tolerance involves the prevention of lethal freeze-induced damage to plasma membrane. We hypothesized that plant membrane resealing, which, in animal cells, is accomplished by calcium-dependent exocytosis following mechanical disruption In Arabidopsis thaliana protoplasts, extracellular calcium enhanced not only but also electroporation, which typically punctures However, did enhance survival when protoplasts were exposed osmotic stress mimicked dehydration....
Microdomains in the plasma membrane (PM) have been proposed to be involved many important cellular events plant cells. To understand role of PM microdomains cold acclimation, we isolated as detergent-resistant fractions (DRMs) from Arabidopsis seedlings and compared lipid protein compositions before after acclimation. The DRM was enriched sterols glucocerebrosides, proportion free increased protein-to-lipid ratio greater than that total fraction. amount recovered DRMs decreased gradually...
Plants are always exposed to various stresses. We have focused on freezing stress, which causes serious problems for agricultural management. When plants suffer freeze-induced damage, the plasma membrane is thought be primary site of injury because its central role in regulation cellular processes. Cold tolerant species, however, adapt such conditions by modifying components and functions (cold acclimation). One most important adaptation mechanisms alteration compositions functions. Advanced...
A detailed analysis of cold acclimation a winter rye (Secale cereale L. cv Puma), oat (Avena sativa Kanota), and spring cultivar (Ogle) revealed that freezing injury leaves nonacclimated seedlings occurred at -2[deg]C in both the cultivars but did not occur until after -4[deg]C. The maximum tolerance was attained all 4 weeks acclimation, temperature which 50% electrolyte leakage decreased to -8[deg]C for oat, -10[deg]C -21[deg]C rye. In protoplasts isolated from expansion-induced lysis...
Using plasma membranes with high purity isolated from winter rye seedlings (Secale cereale L. cv Puma) by an aqueous two-polymer phase partition technique, lipid and protein changes were determined during the development of cold hardiness.The degree fatty acid unsaturation proportions phospholipid classes changed only slightly acclimation. A small change, however, was observed in sterol composition; beta-sitosterol increased gradually a corresponding decrease campesterol plus stigmasterol...
A simplified method for the isolation of a plasma membrane-enriched fraction from plants utilizing an aqueous two-polymer phase system is outlined. Mainly, plant used was Orchard grass (Dactylis glomerata L.). The two-phase consisted 5.6% (w/w) dextran T500 and polyethyleneglycol 4000 in 0.5 molar sorbitol-15 millimolar Tris-maleate (pH 7.3), 30 NaCl. In this system, membranes other were preferentially partitioned into top lower phase, respectively. purity isolated membrane sufficiently high...
Water transport in plants is greatly dependent on the expression and activity of water channels, called aquaporins. Here, we have clarified tissue- cell-specific localization aquaporins rice by immunoblotting immunocytochemistry using seven isoform-specific aquaporin antibodies. We also examined activities typical family members a yeast system combination with stopped-flow spectrophotometry assay. OsPIP1 members, OsPIP2;1, OsTIP1;1 OsTIP2;2 were expressed both leaf blades roots, while...
The chemical composition of plasma membrane fractions isolated from orchard grass seedlings (Dactylis glomerata L.) was analyzed and compared with endomembranes. is characterized by an enrichment sterols a lower degree unsaturation phospholipids. Steryl glycosides were found to be one the lipid components membrane, but steryl esters galactolipids barely detectable. Diphosphatidyl glycerol characteristically detected in mitochondrial not fraction. Plasma mambrane fraction also its ;lower...
The freezing tolerance of protoplasts isolated from nonacclimated rye leaves (Secale cereale L. cv Puma) was significantly altered by using a pH-induced protoplastliposome fusion technique to modify the lipid composition plasma membrane. increase in elicited with liposomes composed either total phospholipid fraction membrane cold-acclimated or single mono- diunsaturated species phosphatidylcholine (PtdCho). Of PtdCho tested, dilinoleoylphosphatidylcholine ([Lin(2)]PtdCho) and...
Cold acclimation process plays a vital role in the survival of chilling- and freezing-tolerant plants subjected to cold temperature stress. However, it remains elusive whether enhances root water uptake (a component chilling tolerance) chilling-sensitive crops such as rice. By analyzing hydraulic conductivity under stress for prolonged time, we found that induced gradual increase osmotic [Lp(r(os))]. Compared with control treatment (roots shoots at 25°C), low (LRT) 10°C; 25°C) dramatically...
To elucidate the fundamental mechanisms and subsequent evolutionary aspects of plant cold acclimation, we examined effect acclimation on freezing tolerance in Klebsormidium flaccidum, a green alga belonging to Charophyceae, sister group land plants. Freezing K. flaccidum was significantly enhanced by treatment: survival increased from 15% at -10 degrees C when grown 18 55 85% after exposure 2 for 7 d, respectively. Accompanying development tolerance, soluble sugars (glucose sucrose),...
Overwintering plants are capable of exhibiting high levels cold tolerance, which is acquired through the process acclimation (CA). In contrast to CA, freezing tolerance rapidly reduced during de-acclimation (DA) and resume growth after sensing warm temperatures. order better understand plant development, aid in breeding cold-tolerant plants, it important decipher functional mechanisms DA process. this study, we performed comparative transcriptomic proteomic analyses CA DA. As revealed by...
Abstract Although light is essential for photosynthesis, it has the potential to elevate intracellular levels of reactive oxygen species (ROS). Since high ROS are cytotoxic, plants must alleviate such damage. However, cellular mechanism underlying ROS-induced leaf damage alleviation in peroxisomes was not fully explored. Here, we show that autophagy plays a pivotal role selective removal ROS-generating peroxisomes, which protects from oxidative during photosynthesis. We present evidence...