Polysome formation in Pinus resinosa at initiation of seed germination

Ribonucleic acid systems present in dormant embryos of red pine(Pinus resinosa Ait.) were studied. Sucrose gradient centrifugationwas used to isolate ribosomes of dormant embryos and embryosimbibed for various times in the light. In dormant embryos,ribosomes existed as monomers. After imbibition, a gradual decreasein the monomers was observed, with subunits and polymers ofribosomes detected within 4 hr. When poly U was added to homogenatesof dormant embryos, formation of polysomes was observed aftera 15-min incubation at 25°C. However, artificial polysomeformation required some factors from heavy particles in thehomogenates. ¹ Contribution from the Missouri Agricultural Experiment Station,Journal Series No. 7079. ² Present address: Government Forest Experiment Station, Meguro,Tokyo, Japan. (Received April 20, 1971; )     

Different Sets of cis-Elements Contribute to the Expression of a Catalase Gene from Castor Bean during Seed Formation and Postembryonic Development in Transgenic Tobacco

Deletion analysis of the promoter region of a gene for catalase,cat2, from castor bean (Ricinus communis) was performed to identifythe cis-regulatory elements responsible for the expression ofa rß-glucuronidase (GUS) fusion gene during seed formationand postembryonic development in transgenic tobacco. The analysisshowed that multiple cis-elements contribute to the activityof the cat2 promoter during seed formation and postembryonicdevelopment. The 5'-upstream regions from –1,241 to –816bp, from –720 to –682 bp, and from –632 to–535 bp, relative to the site of initiation of translationof cat2, contributed positively to the activity of the cat2promoter during both stages. By contrast, the region from –816to –720 bp had a negative effect at both stages. The regionfrom –682 to –632 bp contributed positively to theactivity during seed formation but negatively during postembyonicdevelopment. Histochemical analysis revealed that the multiplecis-elements determined not only the level of expression ofthe chimeric gene but also the tissue-specificity of such expression.For example, the region from –1,241 to –816 bp allowedexpression of the chimeric gene in the axis of the embryo ofthe dry seed, as well as in the cortex of the middle part ofthe hypocotyl and at the base of epicotyl in the young seedling. ¹Present address: Department of Plant Molecular and Cell Biology,University of Florida, Gainesville, Florida 32611-0511, U.S.A. ²Present address: Center for Molecular Biology and Genetics,Mie University, 1515 Kamihama, Tsu, Mie, 519 Japan ³Present address: Faculty of Biotechnology, Fukui PrefecturalUniversity, 4-1-1 Kenjojima, Matsuoka-cho, Yoshida-gun, Fukui,910-11 Japan     

Some Characteristics of Membrane-Associated Protein Kinase in Lemna paucicostata

A protein kinase which phosphorylates histone was isolated fromthe endoplasmic reticulum-rich fractions of Lemna paucicostata.The enzyme could be solubilized by sonication, and its molecularweight was estimated as 220,000 by Sephacryl S-300 gel filtration.The optimum pH for enzyme activity was 9.0–9.5 and theactivity was stimulated by Co^2$, Mg^2$ and Mn^2$. Substrate proteinswhich might be phosphorylated by this protein kinase were alsodetected in microsomal fractions of Lemna plants. ¹ Present address: Advanced Research Laboratory, HITACHI LTD.,Kokubunji, Tokyo 185, Japan.     

Purification and properties of two ribonucleases in different intracellular compartments in pea root tissue.

Two RNases in bound forms associated with the microsomal membrane and with the ribosomes or unknown particles in pea root tissue were solubilized by subjecting the membrane to sonic oscillation in the presence of EDTA and KC1 and by treating the particles with EDTA, respectively. The RNases were than purified by DEAE-cellulose and Sephadex G-75 column chromatographies. The elution profiles of RNases from the columns were very similar. No significant differences were observed in their electrophoretic mobilities in polyacrylamide gels, in molecular weight, in activation by inorganic ions, urea or phospholipid micelles or in the dependence of their activities upon pH. The purified RNASES were not different from the bound enzymes as regards activation by inorganic ions and urea and the dependence of the activity upon pH. Triton X-100 stimulated the activity only if RNase was in a bound form associated with the microsomal membrane. We propose that the two RNases may be the same molecular species and differ only in the form of association with intracellular structures.     

High Affinity of the 5'-Upstream Region of a Winged Bean Chymotrypsin Inhibitor Gene for Nuclear Matrix

The 5'-upstream region of a winged bean chymotrypsin inhibitorgene (WCI-3b) was found to have a high affinity for nuclearmatrix. The region, named WCI-3b MAR (matrix attachment region),is highly A+T-rich and contains multiple sites interacting withnuclear matrix. A MAR was also found in the corresponding regionof the WCI-x gene, another active gene of the WCI family. SeveralMAR-binding proteins were detected in the wheat nuclear matrix. ⁴Present address: Friedrich Miescher Institute, P.O. Box 2543,CH-4002 Basel, Switzerland. ⁵Present address: Research Institute for Biological Sciences(RIBS), Kayo-cho, Jyobo-gun, Okayama, 716–1241 Japan.     

Energy conversion and changes in physical parameters in chloroplasts and subchloroplast particles II. Energy conversion in chloroplasts and different types of subchloroplast particles

The light-induced absorbance change at 515 nm, light-inducedhydrogen ion uptake and ATP formation were compared in chloroplastsand different types of sonicated subchloroplast particles. Noparallel relationship among the activities for ATP formation,hydrogen ion uptake and the 515-nm change was observed in differenttypes of preparations. NH₄Cl inhibited ATP formation in chloroplastsbut had little effect on subchloroplast particles. In contrast,the light-induced hydrogen ion uptake was inhibited by NH₄Clin a similar manner. Tetraphenylboron (TPB), at 1 µM, inhibited ATP formationby about 30% in both chloroplasts and subchloroplast particles.In the presence of TPB, ATP formation in chloroplasts was stronglyinhibited by NHC₄Cl, but in subchloroplast particles the additionalinhibitory effect of NH₄Cl was small. A synergistic inhibitionof photophosphorylation by valinomycin plus NH₄Cl was much clearer.Although acceleration of the recovery of the 515-nm change byNH₄Cl or valinomycin was moderate, the 515-nm change virtuallydisappeared when NH₄Cl and valinomycin were added simultaneously. Although the membrane potential has a major role as the principaldriving force for ATP formation in subchloroplast particles,the simultaneous abolishment of the pH gradient and membranepotential may be required to uncouple ATP formation. ¹Present address: Fukuoka Women's University, Kasumigaoka, Fukuoka813, Japan. ²Present address: Ryukyu University, Naha, Okinawa 903, Japan. (Received February 5, 1974; )     

Phosphoenolpyruvate Carboxylase of Maize Leaves: an Improved Method for Purification and Reduction of the Inhibitory Effect of Malate by Ethylene Glycol and Bicarbonate

Light-adapted and dark-adapted forms of phosphoenolpyruvatecarboxylase were purified from maize leaves by an improved methodthat included chromatography on Butyl-Toyopearl in the presenceof ethylene glycol. The inhibition by malate was relieved notonly by increasing concentrations of ethylene glycol but alsoby bicarbonate at pH 7.0. ¹Present address: NEOS Central Research Laboratory, 1-1 Ohike-machi,Kosei-cho, Shiga, 520-32 Japan. ²Present address: Asahi Medical Co., Ltd., 4-3400-I Asahimachi,Nobeoka, 882 Japan. ³Present address: Chugai Pharmaceutical Co., Ltd., 1-135 Komakado,Gotemba, 412 Japan.     

Inactivation of Photosynthetic Oxygen Evolution and Concomitant Release of Three Polypeptides in the Photosystem II Particles of Spinach Chloroplasts

Photosystem II particles having an oxygen evolution activityas high as 300 µmol mg^–1 chlorophyll hr ^–1were prepared from spinach chloroplasts using Triton X-100.The oxygen evolution system in these particles was stable; 70%of the original activity remained after storage of the particlesat 0?C for 7 days. When the particles were treated at pH 9.3,the oxygen evolution was specifically inactivated and threepolypeptides having apparent molecular weights of 32,000. 24,000and 15,000 were simultaneously released. This observation suggeststhat these polypeptides are associated with the oxygen evolutionsystem of photosynthesis. ¹ Present address: Department of Chemistry, Faculty of Science,Toho University, Miyama 2-2-1, Funabashi, Chiba 274, Japan. (Received January 4, 1982; Accepted February 19, 1982)     

The Deduced Amino Acid Sequence of Phytochrome from Adiantum Includes Consensus Motifs Present in Phytochrome B from Seed Plants

A cDNA for the phytochrome of the fern Adiantum capillus-venerisL. was cloned and sequenced. The deduced phytochrome is 50{smalltilde}55% identical to phytochromes of seed plants, and 68%identical to Selaginella phytochrome. Regions resemble thosein previously characterized phytochromes from ferns, lower plantsand seed plants. ³Present address: Yamanouchi Pharmaceutical Co., Ltd., 21 Miyukigaoka,Tsukuba-shi, Ibaraki, 305 Japan ⁴Present address: Plant Growth Regulation Laboratory, The Instituteof Physical and Chemical Research (RIKEN), Hirosawa 2-1, Wako-shi,Saitama, 351-01 Japan ⁵Present address: Advanced Research Laboratory, Hitachi, Ltd.,Hatoyama, Saitama, 350-03 Japan     

Tentoxin Inhibits Both Photophosphorylation in Thylakoids and the ATPase Activity of Isolated Coupling Factor F1 from the Cyanobacterium Anacystis nidulans

Tentoxin strongly inhibited the ATPase activity of isolatedcoupling factor 1 (AF₁) from the cyanobacterium Anacystis nidulans,with 50% inhibition occurring at 0.3 µM. When thylakoidsfrom A. nidulans were preincubated with 0.3 µM tentoxinfor 30 min, photophosphorylation was inhibited by 50%. Measurementsof fluorescence from 9-aminoacridine indicated that tentoxininhibited the utilization of the proton gradient by ATP formationin thylakoids. These results indicate that tentoxin is a strongenergy-transfer inhibitor of photophosphorylation in A. nidulans.Tentoxin decreased the level of ATP in intact cells both inthe light and in darkness, its effects being much stronger inthe dark. Tentoxin at 50 µM strongly inhibited the growthof the cells. ³Present address: Corporate Research and Development Laboratory,Tonen Co. 1-3-1 Nishi-tsurugaoka, Ohi-machi, Saitama, 354 Japan ⁴Present address: Technology and Engineering Laboratories, AjinomotoCo., Inc. Suzuki-cho 1, Kawasaki, 210 Japan     

Inhibition of Hydroxyquinol Auto-Oxidation by a Cell Extract of Trichosporon cutaneum

A cell extract from acetate-grown Trichosporon cutaneum WY2-2inhibited auto-oxidation of phenolics, especially that of hydroxyquinol.It prevented auto-oxidation of hydroxyquinol without directinteraction with hydroxyquinol. Bovine erythrocyte superoxidedismutase had similar characteristics as the cell extract, andthe elution patterns of superoxide dismutase activity and ofthe inhibitory activity to hydroxyquinol auto-oxidation froma Sephadex G-150 column coincided. These results indicate thatthe inhibitory activity in the cell extract is mainly due tosuperoxide dismutase. High activity of superoxide dismutase(20–30 unit/mg protein) and its isozyme profiles suggestan intimate relation between the regulation of superoxide dismutaseand catabolism of phenolics via hydroxyquinol. ¹Present address: Biological Institute, Faculty of Science,Nagoya University, Nagoya 464, Japan. ²Present address: Shin Nihon Chemical Co. Ltd., 19-10, Showa-cho,Anjoh, Aichi 446, Japan. (Received November 15, 1985; Accepted July 3, 1986)     

Protein synthesis in the embryos of Pinus thunbergii seed I. Influences of imbibition of seeds in the dark

The conditions and requirements of an in vitro protein-synthesizingsystem in the embryos of Pinus thunbergii seeds were studied.Even in the dry seed embryos, the ribosomes retained their syntheticcapacity. Even after imbibition in the dark, the ribosomes didnot show an increase in the activity of protein synthesis. Anincrease in the activity during dark imbibition was found inthe 100,000?g supernatant fraction. The activities of the cell-freesystems prepared from both embryos of dark-imbibed and dry seedswere dependent on the addition of poly U. This suggests thelack or inactivity of messenger RNA in these seed embryos. ¹ Present address: Faculty of Education, Utsunomiya University,Mine-machi, Utsunomiya 320, Japan. (Received July 19, 1976; )     

Anatomical and physiological aspects of developmental processes of adventitious root formation in Azukia cuttings

In Azukia stem cuttings, root primordia always appeared in theinterfascicular regions between the endodermis and the interfascicularcambium. Transverse cell divisions were observed as the first eventsin the process of root formation. They began to occur 10 hrafter cuttings had been made and were restricted to the interfascicularregions about 1 mm above the basal cut end of the cutting. Ineach of interfascicular region, 10 to 20 cells divided. Transversedivisions were followed by longitudinal divisions, which beganto occur 18 hr after cuttings had been made. The early process of root primordium formation is distinguishedby the following three phases: the first phase during whichno cell division occurs (0–8 hr), the second phase duringwhich transverse cell divisions occur (8–16 hr) and thethird phase during which longitudinal divisions occur (16–24hr). Cuttings in each phase responded differently to test substances. ¹Supported in part by Grant No. 139011 from the Ministry ofEducation, Japan. ² Present address: Junior College of Toyo University, Hakusan,Bunkyo-ku, Tokyo 112, Japan. (Received October 24, 1977; )     

Studies on anaerobic biphasic growth of a denitrifying bacterium, Pseudomonas stutzeri

Growth of Pseudomonas stutzeri(VAN NIEL strain) in the presenceof a limiting amount of nitrate under anaerobic conditions ischaracterized by 2 logarithmic phases separated distinctly byan intermediate phase where the growth rate is very low. Inthe first logarithmic phase nitrate is reduced stoichiometricallyto nitrite stage, and in the second phase nitrite is reducedto nitrogen gas. The nitrite reducing activity of cells in the second growthphase is 3–4 times higher than that of cells in the firstphase. The rise in nitrite reducing activity is correlated witha remarkable increase in the content of cytochromes a₂ and c-552. ¹Present address: Department of Biochemistry, Hiroshima UniversitySchool of Dentistry, Hiroshima, Japan. ²Present address: Institute of Molecular Biology, Faculty ofScience, Nagoya University, Nagoya, Japan. (Received June 16, 1969; )     

Ionic Activity Gradients across the Surface Membrane of Cytoplasmic Droplets Prepared from Chara australis

The membrane potential and the ionic activity gradients of K⁺and Cl^– across the surface membrane of cytoplasmic dropletsprepared from Chara australis internodal cells, were measuredin high and low ionic strength bathing solutions using liquidion exchange microelectrodes selective for K⁺ and Cl^–.Our results indicate that K⁺ is close to electrochemical equilibriumwhereas Cl^– is not. ¹ Present address: ICI Japan, Palace Hotel Annex Building, Marunouchi,Tokyo, Japan.     

Action Spectra Confirm Two Separate Actions of Phytochrome in the Induction of Flowering in Lemna paucicostata 441

Action spectra studies have shown that in the short day plant(SDP) Lemna paucicostat441 there are at least two actions ofphytochrome in the induction of flowering. At the beginningof the dark period far-red light inhibited flowering, and theaction spectrum corresponded to the absorption spectrum of P_FR,while at the middle of the inductive dark period both red andfar-red light were inhibitory. The action spectrum for the redlight corresponded to that of PR absorption, but there was activityin the region beyond 720 nm which exactly coincided with theabsorption by P_FR observed at the beginning of the dark period,indicating that at the middle of the dark period there was absorptionby both P_R and P_FR. The difference in quantum efficiency betweenthe red and far-red light effects was about 60-fold. These resultsare consistent with there being a stable pool of P_FR necessaryfor the induction of flowering and another pool of phytochromein a different cellular environment which participates in thenight-break reaction as P_R. ¹ Present address: School of Applied Biology, Faculty of Science,Lancashire Polytechnic, Preston PR1 2TQ, U.K. ² 2 Present address: Division of Environmental Biology, NationalInstitute for Environmental Studies, Yatabemachi, Tsukuba, Ibaraki305, Japan. ³ Present address: Division of Plant Biological Regulation,The Riken Institute for Frontier Research Program, Hirosawa,Wako-shi, 351-01, Japan. (Received December 13, 1986; Accepted July 17, 1987)     

Demonstration of light-induced potential change in Chara cells lacking tonoplast

Chara cells without tonoplasts, prepared by replacing the cellsap with EGTA-containing media, showed essentially the samepattern of light-induced changes in membrane potential and membraneresistance as normal cells although the concentrations of ionsand ATP in the cytoplasm decreased considerably (1/3–1/10)after loss of the tonoplast. Removal of the tonoplast reducedthe rate of photosynthetic O₂ evolution to about 50% of thatof normal cells but did not affect the magnitude of light-inducedpotential change. Not a full but a certain level of electronflow seems necessary to activate the putative electrogenic H⁺-pump. ¹ Present address: Department of Botany, Faculty of Science,University of Tokyo, Japan. ² Present address: Niigata College of Pharmacy, Niigata 950-21,Japan. (Received September 4, 1978; )