scholarly journals The Effects of Development and Salinity Stress on Mannitol Biosynthesis in Celery Leaves

HortScience ◽  
1997 ◽  
Vol 32 (3) ◽  
pp. 491F-492
Author(s):  
J.D. Everard ◽  
W.H. Loescher
Keyword(s):  
Salt Stress ◽  
Leaf Development ◽  
De Novo ◽  
Northern Blotting ◽  
Apium Graveolens ◽  
Fixed Carbon ◽  
Protein Levels ◽  
Mature Leaves ◽  
Young Leaves ◽  
The Relationship

In celery (Apium graveolens L.), up to 50% of newly assimilated carbon may be partitioned into mannitol in mature leaves. Mannitol biosynthesis involves three unique enzymatic steps, and mannose 6-phosphate reductase (M6PR) is the critical regulatory step in the pathway. We measured M6PR enzyme activities, M6PR protein levels (using an immunological method) and M6PR transcript levels (by Northern blotting) to assess effects of leaf development on mannitol biosynthesis. M6PR was limited to green tissues and was under tight transcriptional regulation during leaf initiation, expansion, and maturation. M6PR expression was also closely correlated with the capacity of leaves to partition newly fixed carbon into mannitol (measured by 14C pulse/chase on intact leaves). Previous studies have also shown salt stress to lead to mannitol accumulation in celery. Using the methods outlined above we also investigated the combined effects of salt stress and leaf development on M6PR expression and the capacity of leaves to partition C to mannitol. Under salt stress M6PR expression and the capacity to synthesize mannitol occurred in younger leaves than in control plants. Thus, the increase in mannitol pool size in salt-stressed celery plants is due, in part, to enhanced de novo synthesis in young leaves. The data also confirmed the relationship between development of photosynthetic capacity, mannitol synthesis and M6PR activity. Supported by USDA-NRI grant # 940-1439.

Surface Structure and Chemical Composition of Epicuticular Waxes during Leaf Development of Tilia tomentosa Moench

1991 ◽  
Vol 46 (9-10) ◽  
pp. 743-749 ◽  
Author(s):  
Paul-Gerhard Gülz ◽  
R. B. N. Prasad ◽  
Edith Müller
Keyword(s):  
Chemical Composition ◽  
Coming Out ◽  
Leaf Development ◽  
De Novo ◽  
Epicuticular Waxes ◽  
De Novo Biosynthesis ◽  
Mature Leaves ◽  
Young Leaves ◽  
Tilia Tomentosa ◽  
First Time

Abstract The very young leaflets of silver lime trees (Tilia tomtentosa), just unfolding from buds, con ­ tained a continuous wax layer without any wax sculptures. The wax on young leaves is quite different in yield and composition than that of mature leaves. After unfolding of leaves a very dynamic biosynthesis of most wax lipids was started. Fifteen days after leaf unfolding the de novo biosynthesis of β-amyrenyl acetate and later on of aldehydes could be detected for the first time. The biosynthesis of wax components in silver lime leaves was finished at the end of June and the wax remained nearly constant in amount and composition during the remaining season. At the same time, when β-amyrenyl acetate was found for the first time, wax sculptures were observed in silver lime leaf waxes coming out of the continuous wax layer, exclusively on the upper leaf side. These wax sculptures increased in quantity in the next weeks and resulted in a crystalloid shape of most solitaire quadrangular rodlets. These crystals were remained all over the season and were formed from β-amyrenyl acetate, the dominating main wax compo­nent {ca. 49% wax).

Sorbitol Versus Sucrose as Photosynthesis and Translocation Products in Developing Apricot Leaves

1985 ◽  
Vol 12 (6) ◽  
pp. 657 ◽  
Author(s):  
RL Bieleski ◽  
RJ Redgwell
Keyword(s):  
Leaf Development ◽  
Main Product ◽  
Mature Leaf ◽  
Young Leaf ◽  
Mature Leaves ◽  
Specific Transport ◽  
Young Leaves

Very young apricot leaves behave like the young leaves of most plants; that is, [14C]sucrose is formed as the main product of 14CO2 photosynthesis, and also when the leaves are supplied with [14C]glucose. [14C]sorbitol is not produced, and is poorly metabolized when fed to the leaf. Expanding leaves behave differently: [14C]sorbitol and [14C]sucrose are formed in similar amounts from both 14CO2 and [14C]glucose; and when [14C]sorbitol is supplied, it is readily metabolized and utilized for growth. Mature leaves are different again. They form [14C]sorbitol as the main product from 14CO2 and from [14C]glucose, and they do not metabolize [14C]sorbitol at all. Thus during development, apricot leaves gain but then lose the ability to utilize sorbitol. They also gain and keep the ability to synthesize sorbitol. This suggests that different biochemical paths exist for sorbitol formation and utilization, and that these paths are differently developed in the various stages of leaf development. Although the very young leaves did not synthesize sorbitol from CO2 or glucose, they contained it as their major sugar. Translocation behaviour was therefore studied. Neither the very young leaves nor the expanding leaves export any photosynthate, but the mature leaf rapidly translocates carbohydrate, mainly in the form of sorbitol, to the younger leaves as well as the rest of the plant. [14C]sorbitol supplied to the mature leaf can be recovered in that form from the very young leaf on the same shoot. This further establishes the role of sorbitol in apricot as a specific transport carbohydrate.

scholarly journals Olfactory Response of the Green Lacewing Chrysoperla Externa to Volatile Organic Compounds of Eucalyptus Urograndis

2021 ◽  
Author(s):  
David Jackson Vieira Borges ◽  
Rafael Aparecido Carvalho Souza ◽  
Alberto de Oliveira ◽  
Raquel Maria Ferreira de Sousa ◽  
Jean Carlos Santos
Keyword(s):  
Chemical Composition ◽  
Volatile Organic Compounds ◽  
Essential Oil ◽  
Organic Compounds ◽  
Green Lacewing ◽  
Mature Leaves ◽  
Volatile Organic ◽  
Young Leaves ◽  
The Relationship ◽  
Eucalyptus Urograndis

Abstract The evaluation of the direct effects of the relationship between plants and predators without considering the participation of herbivores can provide vital information for the study of ecological interactions and integrated pest management. In this context, the present work studied the behavioral responses of Chrysoperla externa (Neuroptera: Chrysopidae) larvae to the volatile organic compounds of young and mature, undamaged and damaged leaves of Eucalyptus urograndis (Myrtaceae), and investigate the chemical composition of leaf essential oils and their effects on the green lacewing. The responses of the C. externa larvae to the odors emitted by leaves were evaluated by an experimental behavior test using a Y-tube olfactometer. The essential oil was extracted by hydrodistillation of the young and mature leaves with and without damage. The larvae respond attractively to the volatiles emitted without the participation of herbivores, and it selected preferentially odors emitted by young leaves with simulated herbivory. The chemical composition was analyzed using gas chromatography coupled with mass spectrometry. This research identified 32 compounds; some of them had not been identified in other studies. Young leaves had a higher content of essential oil compared to mature leaves. Among the compounds identified, eucalyptol, α-Terpineol, Aromadendrene, and α-Terpinyl acetate are the major compounds. An inversion in the content of eucalyptol (which decreases) and α-terpinyl acetate (which increases) is observed when young and mature leaves are damage. Thus, this work contributed with basic data on the potential use of eucalyptus forests as maintainers of natural chrysopids populations.

Delayed greening in phosphorus-efficient Hakea prostrata (Proteaceae) is a photoprotective and nutrient-saving strategy

2021 ◽  
Vol 48 (2) ◽  
pp. 218
Author(s):  
Thirumurugen Kuppusamy ◽  
Dorothee Hahne ◽  
Kosala Ranathunge ◽  
Hans Lambers ◽  
Patrick M. Finnegan
Keyword(s):  
Fatty Acids ◽  
Leaf Development ◽  
Developmental Stages ◽  
Saturated Fatty Acids ◽  
Structural Development ◽  
Mature Leaves ◽  
Young Leaves ◽  
Sequential Allocation ◽  
Delayed Greening ◽  
Photosynthetic Machinery

Hakea prostrata R.Br. (Proteaceae) shows a ‘delayed greening’ strategy of leaf development characterised by reddish young leaves that become green as they mature. This trait may contribute to efficient use of phosphorus (P) during leaf development by first investing P in the development of leaf structure followed by maturation of the photosynthetic machinery. In this study, we investigated the properties of delayed greening in a highly P-efficient species to enhance our understanding of the ecological significance of this trait as a nutrient-saving and photoprotective strategy. In glasshouse-grown plants, we assessed foliar pigments, fatty acids and nutrient composition across five leaf developmental stages. Young leaves had higher concentrations of anthocyanin, P, nitrogen (N), copper (Cu), xanthophyll-cycle pigments and saturated fatty acids than mature leaves. As leaves developed, the concentration of anthocyanins decreased, whereas that of chlorophyll and the double bond index of fatty acids increased. In mature leaves, ~60% of the fatty acids was α-linolenic acid (C18:3 n-3). Mature leaves also had higher concentrations of aluminium (Al), calcium (Ca) and manganese (Mn) than young leaves. We conclude that delayed greening in H. prostrata is a strategy that saves P as well as N and Cu through sequential allocation of these resources, first to cell production and structural development, and then to supplement chloroplast development. This strategy also protects young leaves against photodamage and oxidative stress during leaf expansion under high-light conditions.

CDDO Increases Translation of CCAAT Enhancer Binding Protein alpha To Induce Granulocytic Differentiation.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 2458-2458 ◽  
Author(s):  
Steffen Koschmieder ◽  
Francesco D′Alo′ ◽  
Hanna Radomska ◽  
Susumu Kobayashi ◽  
Elena Levantini ◽  
...  
Keyword(s):  
De Novo ◽  
Binding Protein ◽  
Northern Blotting ◽  
Granulocytic Differentiation ◽  
Protein Levels ◽  
Enhancer Binding Protein ◽  
Ccaat Enhancer Binding Protein ◽  
Eif2 Alpha

Abstract The triterpenoid 2-Cyano-3,12-dioxooleana-1,9-dien-28-oic acid (CDDO) is a novel antineoplastic drug which induces apoptosis of a wide variety of tumor cells in vitro and in vivo and leads to granulocytic differentiation of hematopoietic progenitor cells. We studied the effect of CDDO on CCAAT enhancer binding protein alpha (CEBPA), a transcription factor which is critical for granulocytic differentiation. In HL60 myeloblastic cells, CDDO (0.01 to 2 uM) dose-dependently decreased the number of cells in culture and increased the fraction of apoptotic cells. However, at doses which did not induce apoptosis, CDDO increased the number of granulocytic cells, as assessed by morphology, NBT assay, and FACS, and Northern blotting showed an increase of GCSFR and a decrease of c-myc mRNA. Phagocytosis of FITC-labeled E. coli bacteria by these cells was enhanced by CDDO. While CEBPA mRNA was decreased, CEBPA protein was significantly increased within 24 hours of treatment, and this was not abrogated by preincubation with the caspase inhibitor Z-DEVD-fmk, again suggesting that these effects were independent of apoptosis. CDDO increased the ratio of the transcriptionally active isoform p42 and the inactive p30 isoform 3-fold, and gel shift assays showed enhanced DNA binding to a GCSFR promoter probe. Since eukaryotic translation initiation factors (eIF) have been described to alter the CEBPA protein isoform ratio, we studied the effects of CDDO on eiF2 alpha and eiF4E activity. CDDO increased the phosphorylation of eIF4E and decreased the phosphorylation of eIF2 alpha within 5 hours of treatment, and this was associated with an increase of the p42/p30 CEBPA ratio. In the presence of the translation inhibitor cycloheximide, CEBPA protein levels decreased after 2 hours, suggesting that CDDO did not stabilize CEBPA and that de novo protein synthesis was required for the observed effects. The effect of CDDO on the p42/p30 ratio was mimicked by 2-AP, which inhibits eIF2 alpha phosphorylation, but was independent of PPARgamma and TGFß pathways, as demonstrated by preincubation with GW9662, or TGFß1, respectively. In primary blasts from patients with acute myeloid leukemia (AML), the p42/p30 ratio of CEBPA was enhanced by CDDO treatment. In conclusion, CDDO leads to granulocytic differentiation and translational induction of CEBPA protein. Since CEBPA function is impaired in many patients with AML, CDDO may provide a novel treatment approach for these patients.

scholarly journals Malate Accumulation in Different Organs of Mesembryanthemum crystallinum L. Following Age-dependent or Salinity-triggered CAM Metabolism

2004 ◽  
Vol 59 (3-4) ◽  
pp. 223-228 ◽  
Author(s):  
Marta Libik ◽  
Beata Pater ◽  
Stewart Elliot ◽  
Ireneusz Ślesak ◽  
Zbigniew Miszalski
Keyword(s):  
Salt Stress ◽  
Catalase Activity ◽  
Crassulacean Acid Metabolism ◽  
Acid Metabolism ◽  
Mesembryanthemum Crystallinum ◽  
Mature Leaves ◽  
Cam Metabolism ◽  
Age Dependent ◽  
Young Leaves ◽  
High Concentrations

Different organs of Mesembryanthemum crystallinum exhibit differing levels of CAM (Crassulacean acid metabolism), identifiable by quantification of nocturnal malate accumulation. Shoots and also basal parts of young leaves were observed to accumulate high concentrations of malate. It was typically found in mature leaves and especially prominent in plants subjected to salt stress. Small amount of nocturnal malate accumulation was found in roots of M. crystallinum plants following age-dependent or salinity-triggered CAM. This is an indication that malate can be also stored in non-photosynthetic tissue. Measurements of catalase activity did not produce evidence of the correlation between activity of this enzyme and the level of malate accumulation in different organs of M. crystallinum although catalase activity also appeared to be dependent on the photoperiod. In all material collected at dusk catalase activity was greater than it was observed in the organs harvested at dawn.

Karakter Morfologi Daun Ubi Jalar Sebagai Bahan Pangan Suku Dani Distrik Kurulu Jayawijaya

Agrotek ◽  
2018 ◽  
Vol 2 (3) ◽  
Author(s):  
Antonius Suparno ◽  
Opalina Logo ◽  
Dwiana Wasgito Purnomo
Keyword(s):  
Sweet Potato ◽  
Leaf Morphology ◽  
Food Source ◽  
Staple Food ◽  
Sweet Potatoes ◽  
General Outline ◽  
Leaf Vein ◽  
Mature Leaves ◽  
Young Leaves ◽  
Tuber Roots

Sweet potato serves as a staple food for people in Jayawijaya. Many cultivars of sweet potatoes have been cultivated by Dani tribe in Kurulu as foot for their infant, child and adult as well as feeding especially for pigs. Base on the used of sweet potatoes as food source for infant and child, this study explored 10 different cultivars. As for the leaf morphology, it was indentified that the mature leaves have size around 15 � 18 cm. general outline of the leaf is reniform (40%), 60% have green colour leaf, 50% without leaf lobe, 60% of leaf lobes number is one, 70% of shape of central leaf lobe is toothed. Abazial leaf vein pigmentation have purple (40%), and petiole pigmentation is purple with green near leaf (60%), besides its tuber roots, sweet potatoes are also harvested for its shoots and green young leaves for vegetables.

MiR-335-5p Inhibits β-Amyloid (Aβ) Accumulation to Attenuate Cognitive Deficits Through Targeting c-jun-N-terminal Kinase 3 in Alzheimer’s Disease

2020 ◽  
Vol 17 (1) ◽  
pp. 93-101 ◽  
Author(s):  
Dan Wang ◽  
Zhifu Fei ◽  
Song Luo ◽  
Hai Wang
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Transgenic Mice ◽  
Western Blot ◽  
Mrna Expression ◽  
Cognitive Deficits ◽  
Protein Levels ◽  
Amyloid Aβ ◽  
Β Amyloid ◽  
The Relationship

Objectives: Alzheimer's disease (AD), also known as senile dementia, is a common neurodegenerative disease characterized by progressive cognitive impairment and personality changes. Numerous evidences have suggested that microRNAs (miRNAs) are involved in the pathogenesis and development of AD. However, the exact role of miR-335-5p in the progression of AD is still not clearly clarified. Methods: The protein and mRNA levels were measured by western blot and RNA extraction and quantitative real-time PCR (qRT-PCR), respectively. The relationship between miR-335-5p and c-jun-N-terminal kinase 3 (JNK3) was confirmed by dual-luciferase reporter assay. SH-SY5Y cells were transfected with APP mutant gene to establish the in vitro AD cell model. Flow cytometry and western blot were performed to evaluate cell apoptosis. The APP/PS1 transgenic mice were used as an in vivo AD model. Morris water maze test was performed to assess the effect of miR- 335-5p on the cognitive deficits in APP/PS1 transgenic mice. Results: The JNK3 mRNA expression and protein levels of JNK3 and β-Amyloid (Aβ) were significantly up-regulated, and the mRNA expression of miR-335-5p was down-regulated in the brain tissues of AD patients. The expression levels of miR-335-5p and JNK3 were significantly inversely correlated. Further, the dual Luciferase assay verified the relationship between miR-335- 5p and JNK3. Overexpression of miR-335-5p significantly decreased the protein levels of JNK3 and Aβ and inhibited apoptosis in SH-SY5Y/APPswe cells, whereas the inhibition of miR-335-5p obtained the opposite results. Moreover, the overexpression of miR-335-5p remarkably improved the cognitive abilities of APP/PS1 mice. Conclusion: The results revealed that the increased JNK3 expression, negatively regulated by miR-335-5p, may be a potential mechanism that contributes to Aβ accumulation and AD progression, indicating a novel approach for AD treatment.

The nutritional consequences of foraging in primates: the relationship of nutrient intakes to nutrient requirements

1991 ◽  
Vol 334 (1270) ◽  
pp. 161-170 ◽  
Keyword(s):  
Food Selection ◽  
Nutrient Requirements ◽  
Nutrient Intakes ◽  
Protein Levels ◽  
Nutrient Density ◽  
High Nutrient ◽  
Relationship Of ◽  
The Relationship ◽  
High Dietary Protein ◽  
Growth And Reproduction

Many studies have examined the proportion of time that primates devote to feeding on various types of food, but relatively little is known about the intake rates associated with each food. However, the nutritional consequences of foraging can only be interpreted by comparing nutrient intakes with estimated nutrient requirements. The energy available to primates from ingested foods will depend both on the composition of the food and the extent to which various constituents, including fibre fractions, are digested. Both human and non-human primates have relatively low requirements for protein as a consequence of slow growth rates, small milk yields and relatively dilute milk. Because the nutrient demands of growth and reproduction are spread out over time, it appears that primates do not need to seek out foods of particularly high nutrient density, except perhaps during weaning. Although food selection in some species of primates appears to be correlated with the protein concentration of foods, it is unlikely that high dietary protein levels are required, at least when foods of balanced amino acid composition (such as leaves) are included in the diet.

scholarly journals The role of JrPPOs in the browning of walnut explants

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Shugang Zhao ◽  
Hongxia Wang ◽  
Kai Liu ◽  
Linqing Li ◽  
Jinbing Yang ◽  
...  
Keyword(s):  
Tissue Culture ◽  
Production Efficiency ◽  
Phenolic Content ◽  
Leaf Tissue ◽  
Limiting Factor ◽  
Mature Leaves ◽  
Survival Percentage ◽  
Highly Active ◽  
Young Leaves

Abstract Background Tissue culture is an effective method for the rapid breeding of seedlings and improving production efficiency, but explant browning is a key limiting factor of walnut tissue culture. Specifically, the polymerization of PPO-derived quinones that cause explant browning of walnut is not well understood. This study investigated explants of ‘Zanmei’ walnut shoot apices cultured in agar (A) or vermiculite (V) media, and the survival percentage, changes in phenolic content, POD and PPO activity, and JrPPO expression in explants were studied to determine the role of PPO in the browning of walnut explants. Results The results showed that the V media greatly reduced the death rate of explants, and 89.9 and 38.7% of the explants cultured in V media and A media survived, respectively. Compared with that of explants at 0 h, the PPO of explants cultured in A was highly active throughout the culture, but activity in those cultured in V remained low. The phenolic level of explants cultured in A increased significantly at 72 h but subsequently declined, and the content in the explants cultured in V increased to a high level only at 144 h. The POD in explants cultured in V showed high activity that did not cause browning. Gene expression assays showed that the expression of JrPPO1 was downregulated in explants cultured in both A and V. However, the expression of JrPPO2 was upregulated in explants cultured in A throughout the culture and upregulated in V at 144 h. JrPPO expression analyses in different tissues showed that JrPPO1 was highly expressed in stems, young leaves, mature leaves, catkins, pistils, and hulls, and JrPPO2 was highly expressed in mature leaves and pistils. Moreover, browning assays showed that both explants in A and leaf tissue exhibited high JrPPO2 activity. Conclusion The rapid increase in phenolic content caused the browning and death of explants. V media delayed the rapid accumulation of phenolic compounds in walnut explants in the short term, which significantly decreased explants mortality. The results suggest that JrPPO2 plays a key role in the oxidation of phenols in explants after branch injury.

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