Seasonal fluctuation in respiration of aging xylem in relation to heartwood formation in Pinus radiata

1973 ◽  
Vol 51 (4) ◽  
pp. 737-741 ◽  
Author(s):  
Louis Shain ◽  
J. F. Graham Mackay
Keyword(s):  
Transition Zone ◽  
Pinus Radiata ◽  
Enzyme Histochemistry ◽  
Respiratory Activity ◽  
Quantitative Estimation ◽  
Seasonal Fluctuation ◽  
Heartwood Formation ◽  
Malic Dehydrogenase ◽  
Dormant Season ◽  
Glucose 6 Phosphate Dehydrogenase

Respiratory activity in xylem tissues of Pinus radiata was monitored during the growing and dormant seasons by manometry as well as by histochemical localization of malic and glucose-6-phosphate dehydrogenases and by quantitative estimation of malic dehydrogenase. During the dormant season, respiration and activity of malic dehydrogenase were significantly greater (1% probability level) in the transition zone separating sapwood from heartwood than in middle and inner sapwood. These results were supported by enzyme histochemistry, which indicated a substantial increase in activity of glucose-6-phosphate dehydrogenase in the transition zone, particularly during the dormant season. It is suggested that heartwood formation occurs mainly during this time.

Ethylene production in xylem of Pinus radiata in relation to heartwood formation

1973 ◽  
Vol 51 (7) ◽  
pp. 1331-1335 ◽  
Author(s):  
Louis Shain ◽  
W. E. Hillis
Keyword(s):  
Carbon Dioxide ◽  
Pinus Radiata ◽  
Ethylene Production ◽  
Wound Response ◽  
Heartwood Formation ◽  
Seasonal Differences ◽  
Transition Zones ◽  
Phenol Synthesis ◽  
Dormant Season ◽  
Stimulation Of

The production of ethylene by xylem tissues of Pinus radiata was monitored throughout the year. Statistically, significantly greater quantities of ethylene were produced during the winter by transition zones separating sapwood from heartwood than by transition zones during the rest of the year and by middle and inner sapwood during the entire year. Ethylene (5 ppm in air), but not carbon dioxide (27.5% in air), stimulated the production of pinosylvin in sapwood blocks. Phenol synthesis appeared to be preceded by desiccation during both heartwood formation and wound response. Tests with cycloheximide indicated that transition zones are capable of protein synthesis. It was suggested that the auxin-ethylene balance could contribute to quantitative and seasonal differences in ethylene production between the wound and senescent responses (heartwood formation). These and other results suggest that (i) ethylene is involved in stimulation of respiration and phenol synthesis during the wound and senescent responses of xylem tissues of this species, and (ii) heartwood formation takes place mainly in the dormant season during increased metabolic activity in the transition zone.

CHANGES IN ENZYMES OF CARBOHYDRATE METABOLISM IN RAT UTERUS DURING EARLY PREGNANCY

1971 ◽  
Vol 68 (4) ◽  
pp. 805-816 ◽  
Author(s):  
M. A. H. Surani ◽  
P. J. Heald
Keyword(s):  
Energy Requirement ◽  
Lipid Synthesis ◽  
Dry Weight ◽  
Glycolytic Enzymes ◽  
Rat Uterus ◽  
Malic Dehydrogenase ◽  
Phosphogluconate Dehydrogenase ◽  
Tissue Changes ◽  
Implantation Sites ◽  
Glucose 6 Phosphate Dehydrogenase

ABSTRACT The enzymes phosphofructokinase (PFK), pyruvate kinase (PK), isocitric dehydrogenase (ICDH), malic dehydrogenase (MDH), glucose-6-phosphate dehydrogenase (G-6PDH) and 6-phosphogluconate dehydrogenase (6PGDH) have been measured in rat uterus during the first 9 days of pregnancy. It was found that after implantation on day 6, the activities of PFK and PK (the key glycolytic enzymes) increased in terms of dry weight — and in terms of protein in the implantation sites, but decreased in non-implanted tissue. The pentose shunt enzymes changed similarly to those of the glycolytic enzymes. ICDH activity increased in the non-implanted tissue and decreased in the implanted tissue. Changes in malic dehydrogenase were extremely variable and did not show a consistent pattern. Administration of Actinomycin D on day 6 of pregnancy abolished the increase in PK and PFK in the implantation sites and indeed led to a major decrease in activity. This implies that the increased PK and PFK in the implantation sites, arise from a DNA dependent RNA directed synthesis of new enzyme protein. The results are discussed in relation to the energy requirement of the decidualising tissue and the need for increased pentose for RNA synthesis. It is suggested that the extra NADPH resulting from the pentose shunt is involved in increased lipid synthesis.

Enzyme variation in the Anopheles gambiae Giles group of species (Diptera: Culicidae)

1978 ◽  
Vol 68 (1) ◽  
pp. 85-97 ◽  
Author(s):  
S. J. Miles
Keyword(s):  
Anopheles Gambiae ◽  
Natural Populations ◽  
Lactic Dehydrogenase ◽  
Starch Gel Electrophoresis ◽  
Malic Dehydrogenase ◽  
Glycerophosphate Dehydrogenase ◽  
Starch Gel ◽  
Anopheles Gambiae Giles ◽  
Species Specific ◽  
Glucose 6 Phosphate Dehydrogenase

AbstractThe genotypes of chromosomally-identified individuals from natural populations of the known species of the group of Anopheles gambiae Giles were scored for the enzyme protein structural loci coding for adenylate kinase (Adk), α-naphthyl acetate esterase (Est-1, Est-2, Est-3), glutamic-oxaloacetic transaminase (Got), α-glycerophosphate dehydrogenase (αGpd), hexokinase (Hk), isocitric dehydrogenase (Idh), lactic dehydrogenase (Ldh), ‘leucine’ aminopeptidase (Lap-2), malic enzyme (Me), octanol dehydrogenase (Odh), phosphoglucomutase (Pgm-1, Pgm-2), 6-phosphogluconic dehydrogenase (6-Pgd), phosphohexose isomerase (Phi) and superoxide dismutase (Sod), following starch gel electrophoresis. In the material examined, Est-1, Est-2, Est-3, Got, ldh, Lap-2, Odh, Pgm-1, Pgm-2 and Sod were segregating for two or more alleles; unique alleles at the Est-1, Got and Sod loci produced species-specific phenotypes in A. melas (Theo.), species C and species D, respectively. The further sampling of A. merus Dön, populations supported the presence of a unique SOD phenotype by which this species can also be identified. Of the other enzyme systems examined, no activity following electrophoresis was detected for aldolase and fructose-1,6-diphosphatase, and the resolution of acid and alkaline phosphatase, glyceraldehyde-3-phosphate dehydrogenase, glucose-6-phosphate dehydrogenase, malic dehydrogenase and xanthine dehydrogenase was too poor under the particular electrophoretic conditions for genetic analyses of the enzyme phenotypes.

scholarly journals Heritability of Heartwood Formation in Pinus radiata D. Don

Nature ◽  
1965 ◽  
Vol 207 (4994) ◽  
pp. 320-320 ◽  
Author(s):  
J. W. P. NICHOLLS
Keyword(s):  
Pinus Radiata ◽  
Heartwood Formation

Estimation of Pathways of Glucose Metabolism Employing [14C] Glucose

1973 ◽  
Vol 28 (1-2) ◽  
pp. 9-20 ◽  
Author(s):  
Ladislav Kümmel
Keyword(s):  
Methylene Blue ◽  
Glucose Metabolism ◽  
Carbohydrate Metabolism ◽  
Quantitative Estimation ◽  
Inhibitory Effect ◽  
Atp Content ◽  
Glucose 6 Phosphate Dehydrogenase

A method of quantitative estimation of the contribution of the pentose cycle and the Embden-Meyerhof pathway to erythrocyte carbohydrate metabolism employing [1-14C] glucose and [6-14C] glucose, is described. It has been found that the ratio of both pathways changes with time of incubation. The contribution of the pentose cycle to glucose metabolism was about 50% and below 10% after 1 hour and 3-5 hour incubation, respectively. Methylene blue (1.84 × 10-4 м) increased the contribution of the pentose cycle to glucose metabolism from 1.5 times to 7 times after 20 min und 3 hour incubation, respectively. In view of the inhibitory effect of ATP on glucose-6-phosphate dehydrogenase (ᴅ-glucose- 6-phosphate: NADP+ oxidoreductase EC 1.1.1.49) the dependence of the contribution of the pentose cycle to glucose metabolism on the length of incubation may be related to the possible changes of erythrocyte ATP content during the separation and washing of these cells.

Content and distribution of lignans in Taiwania cryptomerioides Hayata

Holzforschung ◽  
2016 ◽  
Vol 70 (6) ◽  
pp. 511-518 ◽  
Author(s):  
Nai-Wen Tsao ◽  
Ying-Hsuan Sun ◽  
Shih-Chang Chien ◽  
Fang-Hua Chu ◽  
Shang-Tzen Chang ◽  
...  
Keyword(s):  
Secondary Metabolites ◽  
Transition Zone ◽  
Tree Species ◽  
Heartwood Formation ◽  
Wood Bark ◽  
Taiwania Cryptomerioides

Abstract Taiwania (Taiwania cryptomerioides Hayata) is one of the economically important tree species indigenous to Taiwan. Hundreds of secondary metabolites have been identified from its wood, bark, root, and needles with lignans as the dominant ones. This substance group contributes a lot to the color, durability, and bioactivities of Taiwaniana. The present paper is dedicated to the quantification of radial and longitudinal lignan distribution. The extractives begin to accumulate largely in the transition zone (TZ), and reach a maximum after finishing the heartwood (hW) formation. Both dibenzyl-γ-butyrolactone type and arylnaphthalide type lignans were found in sapwood (sW) except for the compound taiwanin A. Clearly, the heartwood formation of Taiwania differs from the hitherto known hW formation types and it is suggested to be denominated as Taiwania-type hW formation, where the biosynthesis of extractives begins in the sW and where their accumulation is clearly elevated in the TZ. A generalized biosynthesis scheme of Taiwanin is presented showing the putative relationships among the most important dimeric lignans that lead to the formation of taiwanin type lignans.

scholarly journals HEARTWOOD FORMATION IN PINUS RADIATA (D.DON.)

1954 ◽  
Vol 53 (3) ◽  
pp. 517-524 ◽  
Author(s):  
J. MADDERN HARRIS
Keyword(s):  
Pinus Radiata ◽  
Heartwood Formation

Collection of expressed genes from the transition zone of Cryptomeria japonica in the dormant season

2012 ◽  
Vol 58 (2) ◽  
pp. 89-103 ◽  
Author(s):  
Kazumasa Yoshida ◽  
Norihiro Futamura ◽  
Mitsuru Nishiguchi
Keyword(s):  
Transition Zone ◽  
Cryptomeria Japonica ◽  
Dormant Season

Physiological changes during heartwood formation in young Eucalyptus bosistoana trees

IAWA Journal ◽  
2018 ◽  
Vol 39 (4) ◽  
pp. 382-394 ◽  
Author(s):  
Gayatri Mishra ◽  
David A. Collings ◽  
Clemens M. Altaner
Keyword(s):  
Transition Zone ◽  
Fluorescence Emission ◽  
Histochemical Staining ◽  
Physiological Changes ◽  
Heartwood Formation ◽  
Water Conductivity ◽  
Radial Profiles ◽  
Parenchyma Cells ◽  
Wide Transition ◽  
Old Trees

ABSTRACTEucalyptus bosistoanaF. Muell. is valued for its naturally durable heartwood. As part of anE. bosistoanabreeding programme, we have tested the hypothesis that there is a prolonged transition from sapwood to heartwood in young trees, resulting in a wide transition zone. This needs to be considered when assessing trees for heartwood quantity and quality. Heartwood formation was investigated in radial profiles in cores from bark to bark of 6-year-old trees with conventional and confocal microscopy, and with a range of different staining techniques that visualised the physiological changes taking place in the parenchyma cells. Using immunolabelling with antibodies against histone proteins and α-tubulin, histochemical staining using potassium iodide (I3-KI) and fluorescence emission spectral scanning, we demonstrated that in heartwood nuclei, microtubules, reserve materials (starch) and vacuoles were absent. The observations revealed that 6-year-oldE. bosistoanatrees contained heartwood. The loss of water conductivity by tyloses formation and the death of the parenchyma cells occurred in close proximity resulting in a transition zone of ~1 cm.

scholarly journals Enzyme histochemistry of developing rat oral mucosa.

1981 ◽  
Vol 29 (1) ◽  
pp. 57-64 ◽  
Author(s):  
S Sjögren ◽  
L Hammarström ◽  
A Larsson
Keyword(s):  
Alkaline Phosphatase ◽  
Acid Phosphatase ◽  
Lactate Dehydrogenase ◽  
Succinate Dehydrogenase ◽  
Oral Mucosa ◽  
Adenosine Triphosphatase ◽  
Enzyme Histochemistry ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Developing Rat

The oral mucosa of developing and mature rats was analyzed histochemically for regional enzyme differences. The following enzymes were studied: nonspecific alkaline phosphatase (alkpase), acid phosphatase (acidpase), 5'-nucleotidase (AMPase), adenosine triphosphatase (ATPase), succinate dehydrogenase (SDH), lactate dehydrogenase (LDH), and glucose-6-phosphate dehydrogenase (G-6-pDH). All enzymes were active in the oral mucosa, but regional as well as tissue variations were observed. Epithelium in all regions showed acidpase staining. Oxidoreductases were found in all regions with variations within the epithelium. The epithelium of specific regions stained for alkpase and AMPase, while adjacent epithelium did not. We suggest that the alkpase and AMPase activities are associated with specific functions of the epithelium in these regions.

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