Cultured tobacco (Nicotiana tabacum var Wisconsin 38) cells adapted to grow under osmotic stress synthesize and accumulate a 26 kilodalton protein (osmotin) which can constitute as much 12% of total cellular protein. In NaCl, osmotin occurs in two forms: an aqueous soluble form (osmotin-I) detergent (osmotin II) the approximate ratio 2:3. Osmotin-I has been purified electrophoretic homogeneity, osmotin-II 90% homogeneity. The N-terminal amino acid sequences osmotins I II are identical...

Significance DNA methylation is generally considered an epigenetic mark for transcriptional gene silencing. In this work, we generated loss-of-function mutant alleles of SlDML2 . We characterized the fruits that failed to ripen and discovered required demethylation activation genes important fruit ripening, including involved in pigment flavor synthesis, ethylene synthesis signaling, cell wall hydrolysis. Unexpectedly, found SlDML2-mediated also necessary ripening-induced repression hundreds...

Pectin methylesterase (PME, EC 3.1.11) demethoxylates pectins and is believed to be involved in degradation of pectic cell wall components by polygalacturonase ripening tomato fruit. We have introduced antisense sense chimeric PME genes into elucidate the role fruit development ripening. Fruits from transgenic plants expressing high levels RNA showed <10% wild-type enzyme activity undetectable protein mRNA. Lower fruits was associated with an increased molecular weight methylesterification...

The transfer of cultured tomato cells (Lycopersicon esculentum cv VFNT-Cherry) to a low water potential environment resulted in an increased dry weight fresh ratio accompanied by rapid accumulation proline. Proline content continued increase as osmotic adjustment and growth occurred. initial proline concentration was drop turgor. However, levels with gain turgor during adjustment. Thus, the depended not only on cell potential, or loss but more closely potential. ultimate level adaptation....

Cultured tobacco cells (Nicotiana tabacum L. cv Wisconsin 38) adapted to grow in medium containing high levels of NaCl or polyethylene glycol (PEG) produce several new enhanced polypeptide bands on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The intensities some the (molecular weights 58, 37, 35.5, 34, 26, 21, 19.5, and 18 kilodaltons) increase with increasing adaptation, while other (54, 52, 17.5, 16.5 are reduced. Enhanced 43- 26-kilodalton polypeptides present both...

Osmotic adjustment was studied in cultured cells of tomato (Lycopersicon esculentum Mill cv VFNT-Cherry) adapted to different levels external water potential ranging from -4 bar -28 bar. The intracellular concentrations reducing sugars, total free amino acids, proline, malate, citrate, quaternary ammonium compounds, K(+), NO(3) (-), Na(+), and Cl(-) increased with decreasing potential. At any given level adaptation, the maximum contribution osmotic sugars followed by potassium ions. sucrose...

Pectin methylesterase (PME, EC 3.1.1.11) is an ubiquitous enzyme in the plant kingdom; however, its role growth and development not yet understood. Using transgenic tomato (Lycopersicon esculentum Mill.) fruits that show more than 10-fold reduction PME activity because of expression antisense gene, we have investigated fruit ripening. Our results reduced causes almost complete loss tissue integrity during senescence but shows little effect on firmness Low pericarp modified both accumulation...

An approximation of the entire population (83%) village Lower Nduu, Machakos Kenya, was examined in a cross-sectional study prevalence and intensity schistosomiasis mansoni correlated with morbidity as determined by standard medical examination. The 416 individuals 90 households studied had male:female ratio 44:56 an age structure which more than 50% were below 20. Malaria very low endemicity area intestinal helminths Schistosoma haematobium. S. infection quantitative Kato thick smears...

Cell lines of tobacco (Nicotiana tabacum L. var Wisconsin 38) were obtained which are adapted to grow in media with varying concentrations NaCl, up 35 grams per liter (599 millimolar). Salt-adapted cells exhibited enhanced abilities gain both fresh and dry weight the presence NaCl compared growing medium without (unadapted cells). Tolerance unadapted 10 was influenced by stage growth, highest degree tolerance exponential phase. osmotic potential turgor varied through growth cycle at all...

Cells of Nicotiana tabacum L. var Wisconsin 38 adapted to NaCl (up 428 millimolar) which have undergone extensive osmotic adjustment accumulated Na(+) and Cl(-) as principal solutes for this adjustment. Although the intracellular concentrations correlated well with level adaptation, these ions apparently did not contribute occurred during a culture growth cycle, because increase period most active The average soluble sugars total free amino acids increased function adaptation; however,...

Abstract Salinity is a significant limiting factor to agricultural productivity, impacting about 9 × 10 8 ha of the land surface on earth, an area 3 times greater than all that presently irrigated (17, 18). Reduced productivity occurs as result decreased yields cultivated [about one-third considered be affected by salt (18, 45)], well due restriction expansion into areas are not cultivated. In United States, salinity major and quality irrigation water continues decline this problem will...

Polyamines (PAs) are ubiquitous, polycationic biogenic amines that implicated in many biological processes, including plant growth and development, but their precise roles remain to be determined. Most of the previous studies have involved three amines: putrescine (Put), spermidine (Spd) spermine (Spm), derivatives. We expressed a yeast synthase (ySpdSyn) gene under constitutive (CaMV35S) fruit-ripening specific (E8) promoters Solanum lycopersicum (tomato), determined alterations tomato...

Abstract Transgenic tomato (Solanum lycopersicum) lines overexpressing yeast spermidine synthase (ySpdSyn), an enzyme involved in polyamine (PA) biosynthesis, were developed. These transgenic accumulate higher levels of (Spd) than the wild-type plants and examined for responses to fungal necrotrophs Botrytis cinerea Alternaria solani, bacterial pathogen Pseudomonas syringae pv DC3000, larvae chewing insect tobacco hornworm (Manduca sexta). The Spd-accumulating more susceptible B. plants;...

Cultured tobacco cells ( Nicotiana tabacum L. cv. Wisconsin 38) synthesize a predominant 26-kDa protein upon exposure to abscisic acid (ABA). ABA also accelerates the rate of adaptation unadapted NaCl stress. The ABA-induced is immunologically cross-reactive to, and produces similar pattern peptides after partial proteolysis as, major associated with adaptation. Both have pI values &gt;8.2. synthesis transient unless are simultaneously exposed There an association between increased...

Abstract Polyamines are ubiquitous aliphatic amines that have been implicated in myriad processes, but their precise biochemical roles not fully understood. We carried out metabolite profiling analyses of transgenic tomato (Solanum lycopersicum) fruit engineered to accumulate the higher polyamines spermidine (Spd) and spermine (Spm) bring an insight into metabolic processes Spd/Spm regulate plants. NMR spectroscopic analysis revealed distinct trends wild-type/azygous fruits ripened off vine....

We have purified pectin methylesterase (PME; EC 3.1.11) from mature green (MG) tomato (Lycopersicon esculentum Mill. cv Rutgers) pericarp to an apparent homogeneity, raised antibodies the protein, and isolated a PME cDNA clone λgtll expression library constructed MG poly(A)+ RNA. Based on DNA sequencing, in present study is different that cloned earlier Ailsa Craig (J Ray et al. [1989] Eur J Biochem 174:119-124). are used determine changes gene developing fruits normally ripening Rutgers...

The first enzyme of the shikimate pathway, 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase (EC 4.1.2.15), is induced by wounding potato or tomato tissue. increase in activity associated with elevated amounts as determined immunoblots. specific wound-induced protein synthesis preceded an mRNA encoding this enzyme. tuber, leaf, and stem tissue translated into a precursor polypeptide that recognized antibodies raised against mature from tuber plastids. Wounding also induces phenylalanine...