Publications

rna aptamers that bind to and inhibit the ribosome-inactivating protein, pepocin.	pepocin, isolated from cucurbita pepo, is a ribosome-inactivating protein (rip). rips site-specifically recognize and depurinate an adenosine at position 4324 in rat 28 s rrna, rendering the ribosome incapable of interacting with essential elongation factors. aptamers that target pepocin were isolated from a degenerate rna pool by in vitro selection. a conserved hairpin motif, quite different from the sequence of the toxin-substrate domain in rat 28 s rrna, was identified in the aptamer sequence ...	2000	10671532
effects of solarization and ammonium amendments on plant-parasitic nematodes.	the effects of soil solarization and ammonium bicarbonate or ammonium sulfate against plant-parasitic nematodes on yellow squash (cucurbita pepo) and on vinca (catharanthus roseus) were evaluated at two sites. solarization for 3 weeks in the spring suppressed population levels of belonolaimus longicaudatus, criconemella spp., and dolichodorus heterocephalus throughout the growing season on both crops at both sites. levels of meloidogyne incognita were suppressed initially, but population densiti ...	2000	19271007
[immunocytological localization of iaa in the parenchyma cell and vascular elements in the graft union of cucurbita pepo/cucurbita moschata at the early developmental stage].	immuno-gold localization of iaa in cells of the graft union in the explant internode graft of cucurbita pepo/cucurbita moschata were investigated with electron microscopy. in parenchyma cells near the graft union, the gold particles were mainly accumulated in nucleus, plastid and endoplasmic reticulum, while no gold particles was detected in golgi body, mitochondrion, cell wall and vacuoles. in the differentiating xylem element, the gold particles were labeled in secondary wall and cytoplasm. in ...	2000	12548981
rate response of 1,3-dichloropropene for nematode control in spring squash in deep sand soils.	the soil fumigant 1,3-dichloropropene (1,3-d) formulated with chloropicrin is viewed as a likely alternative for replacing methyl bromide in florida when the latter is phased out in 2005. therefore, it behooves us to learn more about using 1,3-d in deep, sand soils. two trials were conducted on spring squash to determine the most effective rate of 1,3-d for the control of meloidogyne spp. rates tested included 0, 56, 84, 112, and 168 liters/ha of 1,3-d applied broadcast with conventional chisels ...	2000	19271005
yield response of pumpkin and winter squash to simulated cucumber beetle (coleoptera: chrysomelidae) feeding injury.	field studies were conducted to characterize the yield responses of pumpkin, cucurbita pepo l., and wintersquash, cucurbita maxima duch., to simulated striped cucumber beetle, acalymma vittatum (f.), feeding damage. preliminary studies in pumpkin ('spookie') were conducted in 1993, and more complete studies in 1994 and 1995 in pumpkin (spookie), and in 1995 and 1996 in winter squash ('waltham'). plants were artificially injured 1 time at the cotyledon, 1st, 2nd, or 3rd true leaf stages by clippi ...	2000	14658523
purification and characterization of a novel pumpkin short-chain acyl-coenzyme a oxidase with structural similarity to acyl-coenzyme a dehydrogenases.	a novel pumpkin (cucurbita pepo) short-chain acyl-coenzyme a (coa) oxidase (acox) was purified to homogeneity by hydrophobic-interaction, hydroxyapatite, affinity, and anion-exchange chromatography. the purified enzyme is a tetrameric protein, consisting of apparently identical 47-kd subunits. the protein structure of this oxidase differs from other plant and mammalian acoxs, but is similar to the protein structure of mammalian mitochondrial acyl-coa dehydrogenase (acdh) and the recently identif ...	2000	10806249
quiescent intense (qi): a gene that affects young but not mature fruit color intensity in cucurbita pepo.	jack o'lantern, a cultivar of the pumpkin group of cucurbita pepo that has intense-colored young fruits, was crossed with vegetable spaghetti, a cultivar of the vegetable marrow group that has light-colored young fruits and genotype d/d i-1/i-1 i-2/i-2. the f1 plants, regardless of the direction of the cross, had light-colored young fruits. young fruit color was observed to segregate in accordance with a 3 intense: 13 light ratio in the f2, indicating that two genes, one dominant and one recessi ...	2000	10912682
african cucurbita pepo l.: properties of seed and variability in fatty acid composition of seed oil.	pumpkin (cucurbita pepo) seeds are used locally in eritrea to treat tapeworm. seeds were found to be rich in oil (approximately 35%), protein (38%), alpha-tocoferols (3 mg/100 g) and carbohydrate content (approximately 37%). the physico-chemical properties and fatty acid composition of the seed oil were examined. the four dominant fatty acids found are: palmitic c16:0 (13.3%), stearic c18:0 (8.0%), oleic c18:1 (29.0%) and linoleic c18:2 (47.0%). the oil contains an appreciable amount of unsatura ...	2000	10846750
molecular cloning and tissue-specific expression of an anionic peroxidase in zucchini.	a calcium-pectate-binding anionic isoperoxidase (aprx) from zucchini (cucurbita pepo) was purified and subjected to n-terminal amino acid microsequencing. the cdna encoding this enzyme was obtained by reverse transcriptase polymerase chain reaction from a cdna library. it encoded a mature protein of 309 amino acids exhibiting all of the sequence characteristics of a plant peroxidase. despite the presence of a c-terminal propeptide, aprx was found in the apoplast. aprx protein and mrna were found ...	1999	10398715
[study on proteins of allele by using the microisoelectric focusing].	clear protein electrophoresis pattern of single pollen grain from cucurbita pepo l. was obtained with isoelectric focusing and supersensitive stain technique. the results showed that there were two special distributing protein bands near acidity pole. in species i, the two protein bands were a little near to acidity pole and in species ii, that was a little far from acidity pole. in species iii, the two protein bands distributed either like species i or like species ii and the distributed ratio ...	1999	12552897
cloning, expression and n-terminal myristoylation of cpcpk1, a calcium-dependent protein kinase from zucchini (cucurbita pepo l.).	we have isolated a full-length cdna clone (cpcdpk1) encoding a calcium-dependent protein kinase (cdpk) gene from zucchini (cucurbita pepo l.). the predicted amino acid sequence of the cdna shows a remarkably high degree of similarity to members of the cdpk gene family from arabidopsis thaliana, especially atcpk1 and atcpk2. northern analysis of steady-state mrna levels for cpcpk1 in etiolated and light-grown zucchini seedlings shows that the transcript is most abundant in etiolated hypocotyls an ...	1999	10080688
effects of a resistant corn hybrid and fenamiphos on meloidogyne incognita in a corn-squash rotation.	the efficacy of a double-cross corn (zea mays) hybrid (old raccoon selection x t216) x (tebeau selection x mp 307) resistant to meloidogyne incognita as a rotational crop, and fenamiphos treatment for management of root-knot nematode (m. incognita race 1) in squash (cucurbita pepo var. melopepo) was evaluated in field tests during 1996 and 1997. numbers of m. incognita in the soil and root-gall indices were lower on the resistant hybrid than on a commercial cultivar dekalb dk-683. treatment mean ...	1999	19270888
comparative study of the chemical composition and nutritional value of pumpkin seed cake, soybean meal and casein.	the chemical composition and nutritional value of pumpkin (cucurbita pepo) seed cake (psc) were studied and compared with those of casein and soybean meal. crude protein and ether extract content in dry matter of psc was 598.0 g/kg and 124.6 g/kg, respectively, and was higher than the percentage of these components (474.2 and 28.3 g/kg, respectively) in soybean meal used in this experiment. the main fatty acids in psc cake were oleic acid (50.4%) and linoleic acid (29.9%). protein found in psc c ...	1999	10633538
high-resolution structures of three new trypsin-squash-inhibitor complexes: a detailed comparison with other trypsins and their complexes.	an anionic trypsin from atlantic salmon and bovine trypsin have been complexed with the squash-seed inhibitors, cmti-i (cucurbita maxima trypsin inhibitor i, p1 arg) and cpti-ii (cucurbita pepo trypsin inhibitor ii, p1 lys). the crystal structures of three such complexes have been determined to 1.5-1.8 a resolution and refined to crystallographic r factors ranging from 17.6 to 19.3%. the two anionic salmon-trypsin complexes (st-cpti and st-cmti) and the bovine-trypsin complex (bt-cpti) have been ...	1999	10089404
elicitin 172 from an isolate of phytophthora nicotianae pathogenic to tomato.	elicitin 172, an acid protein with elicitor activity, has been isolated in true form from culture filtrates of phytophthora nicotianae, the causal agent of crown and root rot of tomato (lycopersicon esculentum). the m(r) (10,349 +/- 1) of the purified protein, determined by es-ms, is identical to that calculated for parasiticein using the mean isotopic composition and assuming the occurrence of three disulfide bridges. the primary structure of elicitin 172, determined using also maldi-ms experim ...	1999	10192962
characterization of cucumber mosaic virus. v. cell-to-cell movement requires capsid protein but not virions.	to ascertain the importance of amino-terminal proximal capsid protein (cp) sequences in cel-to-cell movement, virion formation, and stabilization, two cp mutants of cucumber mosaic virus (cmv) were generated by deletion of sequences encoding cp amino acids 15-40 (delta sal-nru) or 26-40 (delta sac-nru). wildtype cmv and cmv containing delta sac-nru could infect systemically four host species, although symptoms induced by the two viruses usually were different cmv containing delta sal-nru could o ...	1998	9657941
effect of tunicamycin on the activity and immunoreactivity of ascorbate oxidase (cucurbita pepo medullosa) expressed in cultured green zucchini cells.	ascorbate oxidase activity and immunoreactivity were evaluated in crude tissue extracts obtained from callus cell cultures induced by green zucchini sarcocarp and grown in the presence of tunicamycin, a powerful n-glycosylation inhibitor. tunicamycin at 2 or 4 microg ml(-1) blocked cell growth within a couple of weeks, although a sustained cell viability was observed in the same period. a significant inhibition of total protein synthesis was observed at 10 and 15 days of culture time, with a dec ...	1998	9870353
characterization of spermidine binding to solubilized plasma membrane proteins from zucchini hypocotyls	in this work [14c]spermidine binding to total proteins solubilized from plasma membrane purified from zucchini (cucurbita pepo l.) hypocotyls was investigated. proteins were solubilized using octyl glucoside as a detergent. specific polyamine binding was thermolabile, reversible, ph dependent with an optimum at ph 8.0, and had a kd value of 5 &mgr;m, as determined by glass-fiber-filter assays. sephadex g-25 m gel-filtration assays confirmed the presence of a spermidine-protein(s) complex with a ...	1998	9662539
the uptake of radionuclides by beans, squash, and corn growing in contaminated alluvial soils at los alamos national laboratory.	pinto beans (phaselous vulgaris), sweet corn (zea mays), and zucchini squash (cucurbita pepo) were grown in a field pot study using alluvial floodplain soils contaminated with various radionuclides within los alamos canyon (lac) at los alamos national laboratory, new mexico. soils as well as washed edible (fruit) and nonedible (stems and leaves) crop tissues were analyzed for tritium (3h), cesium (137cs), strontium (90sr), plutonium (238pu and 239,240pu), americium (241am), and total uranium (to ...	1998	9491570
structures of the n-linked carbohydrate of ascorbic acid oxidase from zucchini.	the n-glycan moiety of ascorbic acid oxidase from zucchini (cucurbita pepo) has been described to be a core-pentasaccharide with a xylose [d'andrea et al. (1988) glycoconjugate j 5:151-7]. ascorbic acid oxidase is sometimes used to characterize antibodies directed against carbohydrate determinants on plant glycoproteins. to prevent misinterpretations of immunological data, the structure of the n-glycan of ascorbic acid oxidase has been reinvestigated. the oligosaccharides were released by almond ...	1998	9530960
nucleotide triphosphates are required for the transport of glycolate oxidase into peroxisomes.	all peroxisomal proteins are nuclear encoded, synthesized on free cytosolic ribosomes, and posttranslationally targeted to the organelle. we have used an in vitro assay to reconstitute protein import into pumpkin (cucurbita pepo) glyoxysomes, a class of peroxisome found in the cotyledons of oilseed plants, to study the mechanisms involved in protein transport across peroxisome membranes. results indicate that atp hydrolysis is required for protein import into peroxisomes; nonhydrolyzable analogs ...	1998	9449847
dissecting the diphenylene iodonium-sensitive nad(p)h:quinone oxidoreductase of zucchini plasma membrane.	quinone oxidoreductase activities dependent on pyridine nucleotides are associated with the plasma membrane (pm) in zucchini (cucurbita pepo l.) hypocotyls. in the presence of nadph, lipophilic ubiquinone homologs with up to three isoprenoid units were reduced by intact pm vesicles with a km of 2 to 7 [mu]m. affinities for both nadph and nadh were similar (km of 62 and 51 [mu]m, respectively). two nad(p)h:quinone oxidoreductase forms were identified. the first, labeled as peak i in gel-filtratio ...	1997	12223742
protein transport into higher plant peroxisomes. in vitro import assay provides evidence for receptor involvement.	peroxisome biogenesis requires that proteins be transported from their site of synthesis in the cytoplasm to their final location in the peroxisome matrix or membrane. glyoxysomes are a class of peroxisomes found primarily in germinating seedlings and are involved in mobilizing fatty acids via the glyoxylate cycle and the beta-oxidation pathway. we have used an in vitro assay to study the mechanism(s) of import of proteins into glyoxysomes. results from this assay indicate that the transport pro ...	1997	9112774
root growth inhibition in boron-deficient or aluminum-stressed squash may be a result of impaired ascorbate metabolism.	although cessation of growth is the most apparent symptom of boron deficiency, the biochemical function of boron in growth processes is not well understood. we propose that the action of boron in root meristems is associated with ascorbate metabolism. total inhibition of root growth in squash (cucurbita pepo l.) plants transferred to boron-free medium coincided with a major decrease (up to 98%) in the ascorbate concentration of root apices. under low-boron conditions, in which root growth was pa ...	1996	12226437
cytoplasmic orientation of the naphthylphthalamic acid-binding protein in zucchini plasma membrane vesicles.	polar transport of the plant hormone auxin is blocked by substances such as n-1-naphthylphthalamic acid (npa), which inhibit auxin efflux and block polar auxin transport. to understand how auxin transport is regulated in vivo, it is necessary to discern whether auxin transport inhibitors act at the intra- or extracellular side of the plasma membrane. populations of predominantly in-side-in plasma membrane vesicles were subjected to treatments that reverse the orientation. these treatments, which ...	1996	12226399
variability of fatty acid content in pumpkin seeds (cucurbita pepo l.).	pumpkin (cucurbita pepo l.) seed oil is a common salad oil which is produced in slovenia, hungary and the southern parts of austria. it is dark green and has a high content of free fatty acids. the seed itself can be eaten. due to its colour and the foam formation, the oil cannot be used for cooking. the content of vitamin e, especially gamma-tocopherol, is very high. the oil content of the pumpkin seed is about 50%. the variability in the oil content is very high resulting from a broad genetic ...	1996	8873459
degradation pattern of photosystem ii reaction center protein d1 in intact leaves. the major photoinhibition-induced cleavage site in d1 polypeptide is located amino terminally of the de loop.	photoinhibition-induced degradation of the d1 protein of the photosystem ii reaction center was studied in intact pumpkin (cucurbita pepo l.) leaves. photoinhibition was observed to cause the cleavage of the d1 protein at two distinct sites. the main cleavage generated an 18-kd n-terminal and a 20-kd c-terminal degradation fragment of the d1 protein. this cleavage site was mapped to be located clearly n terminally of the de loop. the other, less-frequent cleavage occurred at the de loop and prod ...	1996	8756500
the n-1-naphthylphthalamic acid-binding protein is an integral membrane protein.	n-1-naphthylphthalmic acid (npa)-binding protein is a plasmalemma (pm) protein involved in the control of cellular auxin efflux. we re-evaluated the spatial relationship of this protein with the pm of zucchini (cucurbita pepo l.) hypocotyls. first, triton x-114 partitioning indicated that the npa-binding protein was more hydrophobic than most pm proteins. second, the npa-binding activity was found to be resistant to proteolytic digestion in membranes. maximum concentrations of binding sites for ...	1996	12226298
effects of pollen selection on progeny vigor in a cucurbita pepo x c. texana hybrid.	we examined the effects of pollen selection for rapid pollen-tube growth on progeny vigor. first, we crossed a wild gourd (cucurbita texana) to a cultivated zucchini (cucurbita pepo cv 'black beauty') to produce an f1 and then an f2 generation. half of the f1 seeds were produced by depositing small loads of c. texana pollen onto the stigmas of c. pepo. these small pollen loads were insufficient to produce a full complement of seeds and, consequently, both the fast- and the slow-growing pollen tu ...	1996	24166555
variability of vitamin e content in pumpkin seeds (cucurbita pepo l.).	pumpkin (cucurbita pepo l.) seed oil is a common salad oil which is produced in the southern parts of austria, slovenia and hungary. it is dark green and has a high content of free fatty acids. due to its colour, the oil cannot be used for cooking. the content of vitamin e, especially gamma-tocopherol, is very high. the oil content of the pumpkin seed is about 50%. the seed itself can be eaten. therefore a pumpkin variety with high vitamin e content is desirable. the aim of this work was to find ...	1996	8638429
polyamine binding to plasma membrane vesicles isolated from zucchini hypocotyls.	the general features of [14c]spermidine binding to plasmalemma vesicles isolated from zucchini (cucurbita pepo l.) etiolated hypocotyls are reported in the present paper. the specific interaction of the polyamine with the plasma membranes was reversible and thermolabile, since it decreased by about 50% in the assay performed at 40[deg]c compared to that carried out on ice. on the contrary, nonspecific binding was unaffected by temperature. specific spermidine binding showed a ph dependence with ...	1996	12226221
transcriptional regulation of hydroxypyruvate reductase gene expression by cytokinin in etiolated pumpkin cotyledons.	to understand the mechanisms by which the expression of a specific gene is modulated by cytokinin, the regulation of hydroxypyruvate reductase (hpr) transcript levels by n6-benzyladenine (ba) in etiolated pumpkin (cucurbita pepo l. cv. halloween) cotyledons was investigated. a pumpkin hpr cdna was generated by reverse transcriptase-polymerase chain reaction and its nucleotide sequence was determined. an antisense hpr rna was prepared for rnase protection analysis of hpr-mrna expression patterns ...	1996	8580766
purification, characterization and subcellular localization of a type-1 ribosome-inactivating protein from the sarcocarp of cucurbita pepo.	the flesh of the fruit of cucurbita pepo contains a type-1 ribosome-inactivating protein (rip), which we named pepocin. pepocin was purified to apparent homogeneity by acid fractionation, ion-exchange chromatography and adsorption chromatography. the protein was found to have a molecular mass of 26 kda and a pi of about 9.9. it does not contain glycosidic linkages. the protein inhibits protein synthesis in a rabbit-reticulocyte lysate with an ic50 (concentration causing 50% inhibition) of 15.4 p ...	1996	9022685
study of the three-dimensional images of potyvirus-induced cytoplasmic inclusions using confocal laser scanning microscopy.	the three-dimensional structure of the cytoplasmic inclusions in leaves of cucurbita pepo l. infected with a singapore isolate of zucchini yellow mosaic virus (zymv-s) was studied using a confocal laser scanning microscope. the cytoplasmic inclusions were found to be linear filamentous structures that varied in thickness and length. the formation of the inclusions probably begins when finely-pointed linear filamentous structures aggregate into bundles forming flat parallel arrays, or diverge int ...	1996	8844619
purification and characterization of assimilatory nitrite reductase from candida utilis.	nitrate assimilation in many plants, algae, yeasts and bacteria is mediated by two enzymes, nitrate reductase (ec 1.6.6.2) and nitrite reductase (ec 1.7.7.1). they catalyse the stepwise reduction of nitrate to nitrite and nitrite to ammonia respectively. the nitrite reductase from an industrially important yeast, candida utilis, has been purified to homogeneity. purified nitrite reductase is a heterodimer and the molecular masses of the two subunits are 58 and 66 kda. the native enzyme exhibits ...	1996	8694757
a spatial analysis of physiological changes associated with infection of cotyledons of marrow plants with cucumber mosaic virus.	changes in host primary metabolism associated with the compatible interaction between cucumber mosaic virus and cotyledons of the marrow plant (cucurbita pepo l.) have been localized, first by measuring activities of key enzymes in infected and uninfected regions of the cotyledon, and second by histochemical techniques applied to tissue prints of the infected region. a series of progressive metabolic changes occurs within the expanding infected lesion. virus replication and the synthesis of vira ...	1996	12226342
ascorbate oxidase from cucurbita pepo medullosa. new method of purification and reinvestigation of properties.	1. ascorbate oxidase has been isolated from the green squash cucurbita pepo medullosa by a new purification method. furthermore a low-molecular-weight copper protein containing one type-1 copper/20000 mr could be separated during the purification of the oxidase. the six-step procedure developed improved the yield of ascorbate oxidase by a factor of 2.5. the method is well reproducible and a constant value of 8 cu (7.95 +/- 0.1/140000 mr) has been established. by ultracentrifugal and electrophore ...	1996	228938
responses of meloidogyne arenaria and m. incognita to green manures and supplemental urea in glasshouse culture.	the recent loss of many effective nematicides has led to renewed interest in alternative methods of nematode management. greenhouse experiments were conducted to determine the effects of rapeseed and velvetbean green manures, and supplemental urea, on the root-knot nematodes meloidogyne arenaria and m. incognita. green manures were incorporated with m. arenaria-infested soil using rates totaling 200,300, and 400 mg n/kg soil. squash plants grown in this soil were evaluated using a gall index and ...	1996	19277190
effects and carry-over benefits of nematicides in soil planted to a sweet corn-squash-vetch cropping system.	the effects of irrigation on the efficacy of nematicides on meloidogyne incognita race 1 population densities, yield of sweet corn, and the carry-over of nematicidal effect in the squash crop were determined in a sweet corn-squash-vetch cropping system for 3 years. fenamiphos 15g and aldicarb 15g were applied at 6.7 kg a.i./ha and incorporated 15 cm deep with a tractor-mounted rototiller. ethylene dibromide (edb) was injected at 18 kg a.i./ha on each side of the sweet corn rows (total 36 kg a.i. ...	1995	19277323
effect of simulated rainfall on leaching and efficacy of fenamiphos.	there is increasing concern in the united states about the pesticide movement in soil, groundwater contamination, and pesticide residue in food. the objective of this study was to determine the efficacy, degradation, and movement of fenamiphos (nemacur 15g) in the soil and residues in squash fruit as influenced by four simulated rainfall treatments (2.5 or 5.0 cm each applied 1 or 3 days after nematicide application) under field conditions. in 1990, concentrations of fenamiphos were greater in t ...	1995	19277322
effect of yard waste compost on plant-parasitic nematode densities in vegetable crops.	the effects of yard-waste compost on densities of plant-parasitic nematodes were determined on four crops at two sites in north florida. separate experiments were conducted with sweet corn (zea mays), cowpea (vigna unguiculata), yellow squash (cucurbita pepo), and okra (hibiscus esculentus). in each test, the design was a randomized complete block replicated four times and involving three treatments: 269 mt/ha yard-waste compost applied to the soil surface as a mulch, 269 mt/ha compost incorpora ...	1995	19277320
rotations with coastal bermudagrass and fallow for management of meloidogyne incognita and soilborne fungi on vegetable crops.	the efficacy of fallow and coastal bermudagrass (cynodon dactylon) as a rotation crop for control of root-knot nematode (meloidogyne incognita race 1) and soilborne fungi in okra (hibiscus esculentus cv. emerald), squash (cucurbita pepo cv. dixie hybrid), and sweet corn (zea mays cv. merit) was evaluated in a 3-year field trial. numbers of m. incognita in the soil and root-gall indices were greater on okra and squash than sweet corn and declined over the years on vegetable crops following fallow ...	1995	19277312
synthesis, cloning and expression in escherichia coli of the gene coding for the trypsin inhibitor from cucurbita pepo.	a chemically synthesized gene coding for the serine proteinase inhibitor cpti ii was cloned in e. coli and its expression was investigated in cytoplasmic and secretion systems. under all conditions investigated the biologically active form of the inhibitor was found only in the latter system, although the yield was rather low.	1995	7653151
characterization of the p1 protein and coding region of the zucchini yellow mosaic virus.	the nucleotide sequence of the 5'-terminal p1 coding region of an aphid-transmissible isolate of zucchini yellow mosaic virus (zymv; strain fl/at), a mild isolate (strain md) and a severe isolate (strain sv), all from florida, were compared with two other zymv isolates. the zymv md and sv isolates and an isolate from california (zymv ca) had 95-98% sequence similarities to fl/at, whereas an isolate from reunion island (zymv ru) had a 60% sequence similarity to fl/at. zymv md had an 18 nucleotide ...	1995	7844540
identification of the proteins responsible for sar dna binding in nuclear matrix of cucurbita pepo.	the nuclear matrices from white bush (cucurbita pepo var. patisonina) cell nuclei have been isolated using three methods: i, standard procedure involving extraction of cell nuclei with 2 m nacl and 1% triton x-100; ii, the same with pre-treatment of cell nuclei with 0.5 mm cuso4 (stabilisation step); and iii, method with extraction by lithium diiodosalicylate (lis), and compared the polypeptide pattern. the isolated matrices specifically bind sar dna derived from human beta-interferon gene in th ...	1995	8588459
galactinol synthase from kidney bean cotyledon and zucchini leaf. purification and n-terminal sequences.	galactinol synthase (gs) was purified 1591-fold with a 3.9% recovery from the cotyledon of kidney bean (phaseolus vulgaris) by a novel scheme consisting of ammonium sulfate fractionation followed by diethylaminoethyl, affi-gel blue, and udp-hexanolamine affinity chromatography. the purified enzyme had a specific activity of 8.75 mumol mg-1 min-1, a ph optimum of 7.0, and requirements for manganese ion and dtt. the enzyme exhibited a km = 0.4 mm for udp-galactose and a km = 4.5 mm for myo-inosito ...	1995	7480343
in search of a reversible stage of photoinhibition in a higher plant: no changes in the amount of functional photosystem ii accompany relaxation of variable fluorescence after exposure of lincomycin-treated cucurbita pepo leaves to high light.	pumpkin (cucurbita pepo l.) leaves in which chloroplast protein synthesis was inhibited with lincomycin were exposed to strong photoinhibitory light, and changes in fo, fm, fv/fm and in the amount of functional photosystem ii (o2 evolution induced by saturating single-turnover flashes) were monitored during the high-light exposure and subsequent dark or low-light incubation. in the course of the photoinhibitory illumination, fm, fv/fm and the amount of functional ps ii declined continuously wher ...	1995	24301535
determination of the quantum efficiency of photosystem ii and of non-photochemical quenching of chlorophyll fluorescence in the field.	a newly developed portable chlorophyll fluorometer in combination with a special leaf clip holder was used for assessing photosynthetic activity of attached sun leaves of fagus sylvatica and cucurbita pepo under field conditions. during diurnal time courses, fluorescence yield, photosynthetic photon flux density (ppfd) incident on the leaf plane, and leaf temperature were measured and quantum efficiency of photosystem ii (ps ii), apparent relative electron transport rates, and non-photochemical ...	1995	28306885
stability of japanese-lacquer-tree (rhus vernicifera) laccase to thermal and chemical denaturation: comparison with ascorbate oxidase.	the thermal denaturation of laccase from the japanese lacquer tree (rhus vernicifera) was studied by differential scanning calorimetry. the endotherms of holo-laccase, type 2-cu-depleted laccase and apo-laccase were deconvoluted into two independent two-state transitions, providing evidence for a domain structure of the protein. the correlation of the two transitions with the bleaching of copper optical bands and the decrease of the transitions' enthalpy on cu removal show that the process invol ...	1995	7702562
immunoglobulins anti-endonuclease 32 kda from cucurbita pepo var patissonina affect process of dna synthesis.	immunoglobulins anti-endonuclease 32 kda inhibit dna synthesis. we observed that low concentrations of iggs (about 50 micrograms igg per 1 x 10(6) cell nuclei) temporary inhibit dna synthesis. this inhibition concerns only the synthesis of dna bound to the nuclear matrix (associated with isolated nuclear matrix). preincubation of cell nuclei of white bush with igg generates longer dna fragments than in controls. involvement of the 32 kda endonuclease or an endonuclease-65 kda protein complex fro ...	1995	8588460
pattern and degree of methylation in ribosomal rna genes of cucurbita pepo l.	methylation with respect to its degree and distribution throughout the 18s, 5.8s and 25s rrna gene clusters (rdna) and within single rdna repeats in seedlings of the higher plant cucurbita pepo l. (zucchini) was investigated. in this plant, which is characterized by several thousand repeats, at least 70% are completely or nearly completely methylated in cpgs and to a lower degree in cpnpgs. detailed methylation analysis revealed that a fraction of about 3-4% of all repeats is hypomethylated near ...	1994	7811974
squash leaf glandular trichome volatiles: identification and influence on behavior of female pickleworm moth [diaphania nitidalis (stoll.)] (lepidoptera: pyralidae).	fourteen volatile compounds occurring in leaf trichomes of yellow squash (cucurbita pepo l. cv. early prolific straightneck) were identified. these compounds accounted for 83.5% of the volatile matrix. ubiquitous constituents of the epidermis (myristic, palmitic, and stearic acids,n-tricosane, andn-pentacosane) accounted for 73.7%; these compounds were not bioassayed. the volatileso-,m-, andp-xylene, toluene, 2-heptanone, (r)-(+)- and (s)-(-)-limonene, and germacrene d were tested for their infl ...	1994	24242732
localization of boron in cell walls of squash and tobacco and its association with pectin (evidence for a structural role of boron in the cell wall).	b deficiency results in a rapid inhibition of plant growth, and yet the form and function of b in plants remains unclear. in this paper we provide evidence that b is chemically localized and structurally important in the cell wall of plants. the localization and chemical fractionation of b was followed in squash plants (curcurbita pepo l.) and cultured tobacco cells (nicotiana tabacum) grown in b-replete or b-deficient medium. as squash plants and cultured tobacco cells became deficient, an incr ...	1994	12232235
efficacy of fenamiphos formulations applied through irrigation for control of meloidogyne incognita on squash.	management ofmeloidogyne incognita by chemigation with fenamiphos was studied in an infested field planted to m. incognita-suscepfible yellow summer squash cv. dixie hybrid. fenamiphos (vl 73.1% a.i. manufacturing concentrate in propylene glycol) was mixed with unitol dsr-90 or used as fenamiphos 3 sc (spray concentrate). both formulations, applied with 63.5 kl irrigation water per hectare, decreased numbers of m. incognita second-stage juveniles in the soil and root-gall indices, and increased ...	1994	19279950
tropical rotation crops influence nematode densities and vegetable yields.	the effects of eight summer rotation crops on nematode densities and yields of subsequent spring vegetable crops were determined in field studies conducted in north florida from 1991 to 1993. the crop sequence was as follows: (i) rotation crops during summer 1991; (ii) cover crop of rye (secale cereale) during winter 1991-92; (iii) 'lemondrop l' squash (cucurbita pepo) during spring 1992; (iv) rotation crops during summer 1992; (v) rye during winter 1992-93; (vi) 'classic' eggplant (solanum melo ...	1994	19279897
effects of tropical rotation crops on meloidogyne arenaria population densities and vegetable yields in microplots.	the effects of 12 summer crop rotation treatments on population densities of meloidogyne arenaria race 1 and on yields of subsequent spring vegetable crops were determined in microplots. the crop sequence was: (i) rotation crops during summer 1991 ; (ii) cover crop of rye (secale cereale) during winter 1991-92; (iii) squash (cucurbita pepo) during spring 1992; (iv) rotation crops during summer 1992; (v) rye during winter 1992-93; (vi) eggplant (solanum melongena) during spring 1993. the 12 rotat ...	1994	19279880
plant virus-induced changes in aphid population development and temporal fluctuations in plant nutrients.	cucurbita pepo plants were infected with zucchini yellow mosaic virus or maintained noninfected.aphis gossypii, which transmits the virus, lived longer and produced more offspring on infected than on noninfected plants. on infected plants, the intrinsic rate of natural increase fora. gossypii increased with time after inoculation. in a similar experiment, concentrations of phloem sap nutrients, including free amino acids, total protein, and sugars from infected and noninfected plants were compar ...	1994	24242121
characterization and sequencing of cdna clone encoding the phloem protein pp2 of cucurbita pepo.	direct n-terminal amino acid sequencing of the phloem protein 2 (pp2) from 3-month old cucurbita pepo l. (pumpkin), purified by sds-page and blotted onto pvdf membrane, showed that the protein had a blocked n-terminus. however, after in situ cleavage of the polypeptide in a gel slice by cyanogen bromide, 75 residues of sequences on two cyanogen bromide fragments were determined. an oligonucleotide probe based on this amino acid sequence was used to screen a cdna library, constructed from mrna of ...	1994	8111014
molecular evolution of the intergenic spacer in the nuclear ribosomal rna genes of cucurbitaceae.	the intergenic spacer (igs) of a 10-kbp repeat (clone prz7d) of the nuclear 18s, 5.8s, and 25s ribosomal rna genes of cucurbita pepo (zucchini) was sequenced and compared to the igs sequences of two other cucurbitaceae, curcurbita maxima (squash), and cucumis sativus (cucumber). the nucleotide sequence and the structural organization of the igs of c. pepo and c. maxima are rather similar (between 75 and 100% sequence similarity depending on the region compared). the igs are mainly composed of th ...	1993	8433383
regulation of purine metabolism in intact leaves of coffea arabica.	the capacity of coffea arabica leaves (5- x 5-mm pieces) to synthesize de novo and catabolize purine nucleotides to provide precursors for caffeine (1,3,7-trimethylxanthine) was investigated. consistent with de novo synthesis, glycine, bicarbonate, and formate were incorporated into the purine ring of inosine 5[prime]-monophosphate (imp) and adenine nucleotides ([sigma]ade); azaserine, a known inhibitor of purine de novo synthesis, inhibited incorporation. activity of the de novo pathway in c. a ...	1993	12232012
effects of mixed cropping on a soil nematode community in honduras.	nematode-resistant tropical legumes are effective in reducing populations of plant-parasitic nematodes when used in rotation systems. mixed cropping is a common practice of many small farmers in central america, but little is known about the effects of tropical legumes on nematode communities under these systems. to examine the effects of intercropping on the nematode fauna associated with squash (cucurbita pepo) and cucumber (cucumis sativa) in honduras, two field experiments were conducted to ...	1993	19279824
protein kinases in zucchini (characterization of calcium-requiring plasma membrane kinases).	using an in situ phosphorylation assay with zucchini (cucurbita pepo l. cv dark green) seedling tissue, we have identified numerous polypeptides that are capable of acting as protein kinases. total protein preparations from different organs contain different kinase profiles, but all are within the range of 55 to 70 kd. at least four kinases are associated with highly purified plasma membranes from etiolated zucchini hypocotyls. the major phosphorylated polypeptides from plasma membranes range in ...	1993	12231949
[main carotenoids in pressed seeds (cucurbitae semen) of oil pumpkin (cucurbita pepo convar. pepo var. styriaca)].	various use of the oil-pumpkin offers reason for the phytochemical analysis of seed-meal's carotene pigments. column chromatography was performed on the adsorbents mgo, celite and caco3 with hexane and benzene as eluents. hplc separation of different pigments was carried out on a 6 microns reverse phase packing with a ternary gradient elution method using a diode-array detector. the main components of the press-residue were lutein [3,3'-dihydroxy-alpha-carotene = (3r,3'r,6'r)-beta,epsilon-carote ...	1993	8249609
the effects of calcium deficiency on cucurbita pepo l. hypocotyl cells: a (31)p nuclear-magnetic-resonance study.	calcium deficiency in zucchini (cucurbita pepo l.) is associated with reduced growth and a reduced ability to transport auxin (allan and rubery, 1991, planta 183, 604-612). an investigation of the effects of calcium-deficiency on zucchini hypocotyl cells was made using weak-acid uptake and (31)p-nuclear-magneticresonance ((31)p-nmr) spectroscopy in vivo and in tissue extracts. calcium-deficient tissue had the same cytoplasmic and vacuolar phs as normal tissue when extracellular ph was near neutr ...	1993	24178486
sphingolipid long-chain base synthesis in plants (characterization of serine palmitoyltransferase activity in squash fruit microsomes).	the activity of serine palmitoyltransferase (palmitoyl-coenzyme a [coa]:l-serine [ser]-c-palmitoyltransferase [decarboxylating], ec 2.3.1.50), the enzyme catalyzing the first step in the synthesis of the long-chain base required for sphingolipid assembly, has been characterized in a plant system. enzyme activity in a microsomal membrane fraction from summer squash fruit (cucurbita pepo l. cv early prolific straightneck) was assayed by monitoring the incorporation of l-[3h]ser into the chloroform ...	1993	12232036
exhaustive removal of n-glycans from ascorbate oxidase: effect on the enzymatic activity and immunoreactivity.	purified ascorbate oxidase from cucurbita pepo medullosa has been subjected to enzymatic deglycosylation using peptide n-glycosidase f. experimental conditions were chosen to obtain efficiently deglycosylated and active ascorbate oxidase: in particular, three different detergent solutions were added separately to the incubation mixtures prior to the peptide n-glycosidase f. the detergent solution made of 0.1% (w/v) sodium dodecyl sulphate + 0.5% (v/v) nonidet p-40 proved to be the only one effec ...	1993	8130388
evidence for a single naphthylphthalamic acid binding site on the zucchini plasma membrane.	the binding of [2,3,4,5,(n)-3h]n-1-napthylphthalamicacid ([3h]-npa) to zucchini (cucurbita pepo l.) plasma membranes was examined in detail using two different filtration assays and the results were rigorously analyzed by saturation curves, double-reciprocal plots, scatchard plots, hill plots, and the computer program ligand (p.j. munson, d. rodbard [1980] anal biochem 107: 220-239). to facilitate these analyses, a new assay that allows rapid and quantitative analysis of [3h]npa binding with hig ...	1993	12231953
vapor heat treatment for zucchini infested with bactrocera cucumis (diptera: tephritidae).	zucchini, cucurbita pepo l., infested with 22-h-old eggs of bactrocera cucumis (french) were completely disinfested using a vapor heat treatment of 45 degrees c with > 94% rh for 30 min. an estimated total of 178,219 eggs (22 h old) was treated without survivors, thus achieving probit 9 mortality. twenty-two-h-old eggs were significantly more tolerant of heat than first, second, or third instars. all treatments were done in a sanshu model ehk-1000b vapor heat treatment system.	1993	8432953
characterization of auxin-binding proteins from zucchini plasma membrane.	we have previously identified two auxin-binding polypeptides in plasma membrane (pm) preparations from zucchini (cucurbita pepo l.) (hicks et al. 1989, proc. natl. acad. sci. usa 86, 4948-4952). these polypeptides have molecular weights of 40 kda and 42 kda and label specifically with the photoaffinity auxin analog 5-n3-7-3h-iaa (azido-iaa). azido-iaa permits both the covalent and radioactive tagging of auxin-binding proteins and has allowed us to characterize further the 40-kda and 42-kda polyp ...	1993	11536546
slow degradation of the d1 protein is related to the susceptibility of low-light-grown pumpkin plants to photoinhibition.	photoinhibition of photosystem ii (psii) electron transport and subsequent degradation of the d1 protein were studied in pumpkin (cucurbita pepo l.) leaves developed under high (1000 mumol m(-2) s(-1)) and low (80 mumol m(-2) s(-1)) photon flux densities. the low-light leaves were more susceptible to high light. this difference was greatly diminished when illumination was performed in the presence of chloramphenicol, indicating that a poor capacity to repair photodamaged psii centers is decisive ...	1992	16653122
proton-transport activity, sidedness, and morphometry of tonoplast and plasma-membrane vesicles purified by free-flow electrophoresis from roots of lepidium sativum l. and hypocotyls of cucurbita pepo l.	large-scale preparations of highly purified tonoplast and plasma-membrane vesicles were obtained from roots (garden cress, lepidium sativum l.) and shoots (etiolated zucchini hypocotyl, cucurbita pepo l.) of representative dicotyledonous seedlings. when tonoplast-enriched fractions of cress roots were prepared by centrifugation and then subjected to free-flow electrophoresis a highly purified tonoplast fraction was obtained. this fraction from cress roots was characterized by morphometry of fili ...	1992	24186777
operation of the xanthophyll cycle in higher plants in response to diurnal changes in incident sunlight.	changes in the carotenoid composition of leaves in response to diurnal changes in sunlight were determined in the crop species helianthus annuus l. (sunflower), cucurbita pepo l. (pumpkin), and cucumls sativus l. (cucumber), in the diaheliotropic mesophyte malva neglecta wallr., and in the perennial shrub euonymus kiautschovicus loesner. large daily changes were observed in the relative proportions of the components of the xanthophyll cycle, violaxanthin (v), antheraxanthin (a), and zeaxanthin ( ...	1992	24186736
subthreshold changes in excitable membranes of cucurbits pepo l. stem cells during cooling-induced action-potential generation.	the nature of subthreshold changes in excitable plasma membranes has been investigated in stem parenchyma cells of cucurbita pepo l. during action-potential generation induced by gradual cooling (from 23 to 10 ° c). the character of the subthreshold depolarization of excitable cells is shown to be mainly defined by a decrease in the activity of the plasma-membrane electrogenie pump (h(+)-atpase). in its turn, the pump activity is controlled by thermal changes in the structure of the membrane lip ...	1992	24186654
flavonoids and flavonoid sulphates as probes of auxin-transport regulation in cucurbita pepo hypocotyl segments and vesicles.	the accumulation of iaa by sealed microsomal vesicles prepared from hypocotyls of dark-grown cucurbita pepo l. (zucchini) seedlings was stimulated by n-1-naphthylphthalamic acid (npa: an inhibitor of carrier-mediated auxin efflux and hence of polar auxin transport) as well as by quercetin and certain other flavonoids with a specificity pattern similar to that previously shown for their npa-like effects on auxin transport and inhibition of npa binding to saturable sites. in contrast, putatively n ...	1992	24186794
localization of galactinol, raffinose, and stachyose synthesis in cucurbita pepo leaves.	the biochemical pathway of stachyose synthesis was localized by immunocytochemical and (14)c-labeling techniques in mature cucurbita pepo l. leaves. galactinol synthase (gas; ec 2.4.1.123), the first unique enzyme in this pathway, was immunolocalized within the intermediary cells of minor veins in conventionally fixed and cryo-fixed, resin-embedded sections using polyclonal anti-gas antibodies and protein a-gold. intermediary cells are specialized companion cells with extensive symplastic connec ...	1992	24178325
phytotropin-binding sites and auxin transport in cucurbita pepo: evidence for two recognition sites.	two properties of phytotropins, their ability to bind to 1-n-naphthylphthalamic acid (npa) receptors located on microsomal vesicles isolated from cucurbita pepo l. hypocotyls, and to stimulate auxin (indol-3-yl acetic acid, iaa) accumulation into such vesicles by blocking its efflux from them, were assessed in double labelling experiments using [2,3,4,5-(3)h]1-n-naphthylphthalamic acid and 3-indolyl-[2-(14)c]acetic acid. two sites of differing affinities and activities on iaa accumulation were f ...	1992	24178053
alatae production and population increase of aphid vectors on virus-infected host plants.	zucchini yellow mosaic virus (zymv) and aphis gossypii glover are two components of a recently identified plant-parasite system that provides an excellent opportunity to study interrelations between a virus and a vector that share the same host, but have no direct physiological interaction. in a field experiment we documented numbers of alate and apterous a. gossypii on healthy cucurbita pepo and on plants inoculated with virus 0, 7, 14, and 21 days before aphid infestation. when plants were ino ...	1992	28311813
proton transport and phosphorylation of tonoplast polypeptides from zucchini are stimulated by the phospholipid platelet-activating factor.	the ether phospholipid platelet-activating factor and certain similar phospholipids, including lysophosphatidylcholine, are known to stimulate both h(+) transport and protein phosphorylation in plant microsomal membranes. in the present work, several polypeptides in highly purified tonoplast membranes from zucchini (cucurbita pepo l.) showed platelet-activating factor-dependent phosphorylation. comparison of protein phosphorylation in different membrane fractions separated by sucrose step densit ...	1992	16669084
a rapid method for isolating glandular trichomes.	a physical method is described for the rapid isolation of plant trichomes, with emphasis on stalked glandular types. the technique involved breaking frozen trichomes with powdered dry ice and collection of glandular heads by sieving from larger tissue fragments. this method was applied to several plants that bear similar stalked trichomes: geranium (pelargonium), potato (solanum tuberosum), tomato (lycopersicon esculentum), squash (cucurbita pepo), and velvetleaf (abutilon theophrasti). the tiss ...	1992	16668834
effects of rapeseed and vetch as green manure crops and fallow on nematodes and soil-borne pathogens.	in a rapeseed-squash cropping system, meloidogyne incognita race 1 and m. javanica did not enter, feed, or reproduce in roots of seven rapeseed cultivars. both nematode species reproduced at low levels on roots of the third crop of rapeseed. reproduction of m. incognita and m. javanica was high on squash following rapeseed, hairy vetch, and fallow. the application of fenamiphos suppressed (p = 0.05) root-gall indices on squash following rapeseed, hairy vetch, and fallow; and on dwarf essex and c ...	1992	19283212
blue light activates a specific protein kinase in higher plants.	blue light mediates the phosphorylation of a membrane protein in seedlings from several plant species. when crude microsomal membrane proteins from dark-grown pea (pisum sativum l.), sunflower (helianthus annuus l.), zucchini (cucurbita pepo l.), arabidopsis (arabidopsis thaliana l.), or tomato (lycopersicon esculentum l.) stem segments, or from maize (zea mays l.), barley (hordeum vulgare l.), oat (avena sativa l.), wheat (triticum aestivum l.), or sorghum (sorghum bicolor l.) coleoptiles are i ...	1992	16653043
characterization of gtp binding and hydrolysis in plasma membranes of zucchini.	we have investigated the possibility that g-protein-like entities may be present in the plasma membrane (pm) of zucchini (cucurbita pepo l.) hypocotyls by examining a number of criteria common to animal and yeast g-proteins. the gtp binding and hydrolysis characteristics of purified zucchini pm are similar to the characteristics of a number of known g-proteins. our results demonstrate gtp binding to a single pm site having a kd value between 16-31 nm. this binding has a high specificity for g ...	1992	11542503
crop rotation studies with velvetbean (mucuna deeringiana) for the management of meloidogyne spp.	results from a greenhouse experiment at cabrils, spain, with two velvetbean (mucuna deeringiana) accessions (florida and mozambique) growing in sterilized sandy loam and inoculated with meloidogyne arenaria race 2, m. incognita race 1, and m. javanica revealed that the legume was not a host for these nematodes. in contrast, roots of 'clemson spineless' okra (hibiscus esculentum), 'summer crookneck' squash (cucurbita pepo), and 'davis' soybean (glycine max) were galled by all three root-knot nema ...	1992	19283043
peroxidase as a developmental marker in plant tissue culture.	peroxidase was studied as a developmental marker in pumpkin (cucurbita pepo l.) callus lines and horse-radish (armoracia lapathifolia gilib) transformants. embryogenic callus lines de grown on ms medium with 2.4-d and na-3 grown on medium with naa and adenine sulfate showed about a 20 times higher enzyme activity than the habituated non-embryogenic line z5b/t grown on medium without hormones. a rise in peroxidase activity indicated that somatic embryogenesis was triggered in a few habituated tis ...	1991	1667582
differential replication in zucchini squash of a cucumber mosaic virus satellite rna maps to rna 1 of the helper virus.	cucumber mosaic virus (cmv) supports the replication and encapsidation of its satellite rna, both in solanaceous and cucurbit host plants; however, different strains of cmv support the replication of satellite rnas with different efficiency. in addition, replication of satellite rna is very efficient in solanaceous host plants and generally poor in cucurbit host plants. the wl1-satellite (wl1-sat) rna is an exception, and replicates to high levels in both solanaceous and curcubit host plants wit ...	1991	1704659
the influence of plant growth regulators on callus induction in pumpkin (cucurbita pepo l.) hairy roots.	following in vitro infection with agrobacterium rhizogenes wild strain (mannopine, 8196) and two a. tumefaciens transconjugant strains (c58c1 para4abc and c58c1 para4b) transformed (hairy) roots were induced in pumpkin (c. pepo l.) cotyledons. the presence of pri t-dna in pumpkin long-term hairy root cultures was determined by southern hybridization. the influence of plant growth regulators on callus induction in root explants from hairy root lines, which differed mutually in morphology and grow ...	1991	1814408
infectious in vitro rna transcripts derived from cloned cdna of the cucurbit potyvirus, zucchini yellow mosaic virus.	a full-length cdna clone of the rna genome of the cucurbit potyvirus zucchini yellow mosaic virus (zymv) was constructed downstream from a bacteriophage t7 rna polymerase promoter. a single extra guanosine residue not present in zymv rna was added to the 5' and 3' ends. capped (m7gpppg) zymv rna transcripts were infectious in 10 of 91 cucurbita pepo test plants; uncapped rna transcripts were not infectious. the appearance of symptoms in plants inoculated with the infectious transcript was delaye ...	1991	1940860
membranes markers in highly purified clathrin-coated vesicles from cucurbita hypocotyls.	the two plasma-membrane (pm) markers: 1,3-β-glucan synthase and naphthylphthalamic-acid-binding capacity are localized in two peaks of activity on isopycnic ficoll/d2o gradients prepared from a zucchini (cucurbita pepo l.) hypocotyl post-microsomal fraction. the denser peak overlaps with the major distribution of clathrin and represents a region of the gradient enriched in coated vesicles (cv). further purification of the pooled cv-fractions has shown that these pm marker activities are not born ...	1991	24193754
small light-harvesting antenna does not protect from photoinhibition.	high-light-induced decrease in photosystem ii (psii) electron transfer activity was studied in high- and low-light-grown pumpkin (cucurbita pepo l.) plants in vivo and in vitro. the psii light-harvesting antenna of the low-light leaves was estimated to be twice as big as that of the high-light leaves. the low-light leaves were more susceptible to photoinhibition in vivo. however, thylakoids isolated from these two plant materials were equally sensitive to photoinhibition when illuminated in the ...	1991	16668423
in vitro effects of monoterpenes on chloroplast membranes.	a chloroplast preparation was extracted from squash (cucurbita pepo (l.) var. senator). enrichment of intact chloroplasts was achieved by continuous free-flow electrophoresis. the addition of monoterpenes, detergent and free fatty acids changed the elecrophoretic separation pattern characteristically. monoterpene-dependent degradation of envelope membranes could be prevented by addition of α-tocopherol prior to monoterpene incubation.photosynthetic electron transport of photosystem ii was comple ...	1991	24414970
stimulation by auxin of phospholipase a in membrane vesicles from an auxin-sensitive tissue is mediated by an auxin receptor.	microsomal vesicles were prepared from zucchini (cucurbita pepo l.) hypocotyls containing radioactive phosphatidylethanolamine or phosphatidylcholine, and these lipids were used as substrates by phospholipase a which is activated by auxins. phospholipase d and phospholipase c hydrolysed the same substrates but were not influenced by auxin. phospholipase a was activated by the auxins indolyl-3-acetic acid, 2,4-dichlorophenoxyacetic acid and, to a lesser extent, by α-naphthaleneacetic acid whereas ...	1991	24186343
expression of ascorbic acid oxidase in zucchini squash (cucurbita pepo l.).	the expression of ascorbic acid oxidase was studied in zucchini squash (cucurbita pepo l.), one of the most abundant natural sources of the enzyme. in the developing fruit, specific activity of ascorbic acid oxidase was highest between 4 and 6 days after anthesis. protein and mrna levels followed the same trend as enzyme activity. highest growth rate of the fruit occurred before 6 days after anthesis. within a given fruit, ascorbic acid oxidase activity and mrna level were highest in the epiderm ...	1991	16668145
plant development in long-term embryogenic callus lines of cucurbita pepo.	embryogenic callus derived from pumpkin hypocotyl segments was induced and maintained for 15 years on ms medium supplemented with the auxins iba (4.9 μm), 2, 4-d (4.5 μm) or iaa (5.7 μm). on induction media continued embryo maturation and development of adult plants typically failed. therefore, small embryogenic clumps and individually isolated embryos were subcultured two to four times on one of the conversion media: ms supplemented with 1.5% sucrose and (a) no hormone, (b) 2.9 μm iaa, (c) 5.7 ...	1991	24213663
somatic embryogenesis and plant regeneration of squash cucurbita pepo l cv. yc 60.	plant regeneration from tissue cultures of summer squash, cucurbita pepo l., cv. yc60, has been observed. somatic embryos organized from shoot apex derived callus cultured on murashige and skoog (ms) medium supplemented with 1.2 mg/l 2,4,5-trichlorophenoxyacetic acid, 0.8 mg/l benzylaminopurine, and 0.1 mg/l kinetin. embryos developed into plantlets by transfer of immature somatic embryos to ms medium with 0.05 mg/l naa and 0.05 mg/l kinetin. regenerated plants appeared morphologically normal an ...	1991	24213662
calcium deficiency and auxin transport in cucurbita pepo l. seedlings.	hypocotyls of cucurbita pepo l. (zucchini) seedlings grown at low calcium levels (0.1 mm) showed reduced basipetal polar transport of the auxins indole-3-acetic acid and 1-naphthylacetic acid in comparison with control plants grown at 5 mm ca(2+). the contribution to overall transmembrane auxin transport of the symport uptake carrier was unchanged by calcium deficiency, but the efflux carrier of the auxin-anion uniport was less active and the sensitivity of auxin transport to n-1-naphthylphthala ...	1991	24193855
phytochrome-mediated detection of changes in reflected light.	measurements of phytochrome photoequilibria and photoconversion rates in vivo, in seedlings of cucurbita pepo l. exposed to light in growth chambers, indicate that significant changes in the state of phytochrome can be brought about by changes in the quality and quantity of the light reflected from the walls of the growth chambers. the changes in reflected light, although large, were small in terms of the total radiation (direct light from the lamps plus wall-reflected light) to which the seedli ...	1991	16667942
two genes encoding 1-aminocyclopropane-1-carboxylate synthase in zucchini (cucurbita pepo) are clustered and similar but differentially regulated.	a 17-kilobase (kb) region of the zucchini (cucurbita pepo) genome has been sequenced and contains two genes, cp-acc1a and cp-acc1b, encoding 1-aminocyclopropane-1-carboxylate synthase (acc synthase; s-adenosyl-l-methionine methylthioadenosine-lyase, ec 4.4.1.14). the genes are transcribed convergently and are separated by a 5.7-kb intergenic region. their coding regions are interrupted by four introns located in identical positions. while the dna identity in their coding regions is 97%, their 5' ...	1991	1871117
purification and characterization of galactinol synthase from mature zucchini squash leaves.	galactinol synthase catalyzes the first committed step in the biosynthesis of raffinose sugars. previous attempts to purify the enzyme have proven difficult and have resulted in low quantities of unpurified enzyme. galactinol synthase was purified 752-fold from mature zucchini (cucurbita pepo l. cv burpee hybrid) leaves using sequential liquid chromatography on de 52, octyl-sepharose cl-4b, and sephacryl s-200. this isolation scheme resulted in an 18.6% recovery of the initial activity. the puri ...	1991	16668244
treatment of benign prostatic hyperplasia with phytosterols.	in a randomised, double-blind study, the preparation curbicin, obtained from pumpkin seeds and dwarf palm plants (cucurbita pepo l. and sabal serrulata), was compared with a placebo in the treatment of symptoms caused by prostatic hyperplasia; 53 patients took part in the study, which was carried out over a 3-month period. urinary flow, micturition time, residual urine, frequency of micturition and a subjective assessment of the effect of treatment were all significantly improved in the treatmen ...	1990	1702340
temperature-dependent changes in photosystem ii heterogeneity support a cycle of photosystem ii during photoinhibition.	high light treatments were given to attached leaves of pumpkin (cucurbita pepo l.) at room temperature and at 1°c where the diffusion- and enzyme-dependent repair processes of photosystem ii are at a minimum. after treatments, electron transfer activities and fluorescence induction were measured from thylakoids isolated from the treated leaves. when the photoinhibition treatment was given at 1°c, the photosystem ii electron transfer assays that were designed to require electron transfer to the p ...	1990	24420463