scholarly journals Expression of an 11 kDa methionine-rich delta-zein in transgenic soybean results in the formation of two types of novel protein bodies in transitional cells situated between the vascular tissue and storage parenchyma cells

2004 ◽  
Vol 2 (3) ◽  
pp. 199-210 ◽  
Author(s):  
Won-Seok Kim ◽  
Hari B. Krishnan
Keyword(s):  
Vascular Tissue ◽  
Protein Bodies ◽  
Transgenic Soybean ◽  
Parenchyma Cells ◽  
Storage Parenchyma ◽  
Transitional Cells ◽  
And Storage ◽  
Novel Protein

Cellular pathways of source leaf phloem loading and phloem unloading in developing stems of Sorghum bicolor in relation to stem sucrose storage

2015 ◽  
Vol 42 (10) ◽  
pp. 957 ◽  
Author(s):  
Ricky J. Milne ◽  
Christina E. Offler ◽  
John W. Patrick ◽  
Christopher P. L. Grof
Keyword(s):  
Sorghum Bicolor ◽  
Cell Walls ◽  
Phloem Loading ◽  
Vascular Bundles ◽  
Phloem Unloading ◽  
Parenchyma Cells ◽  
Storage Parenchyma ◽  
Sucrose Storage ◽  
Cellular Pathways ◽  
And Storage

Cellular pathways of phloem loading in source leaves and phloem unloading in stems of sweet Sorghum bicolor (L.) Moench were deduced from histochemical determinations of cell wall composition and from the relative radial mobilities of fluorescent tracer dyes exiting vascular pipelines. The cell walls of small vascular bundles in source leaves, the predicted site of phloem loading, contained minimal quantities of lignin and suberin. A phloem-loaded symplasmic tracer, carboxyfluorescein, was retained within the collection phloem, indicating symplasmic isolation. Together, these findings suggested that phloem loading in source leaves occurs apoplasmically. Lignin was restricted to the walls of protoxylem elements located in meristematic, elongating and recently elongated regions of the stem. The apoplasmic tracer, 8-hydroxypyrene-1,3,6-trisulfonic acid, moved radially from the transpiration stream, consistent with phloem and storage parenchyma cells being interconnected by an apoplasmic pathway. The major phase of sucrose accumulation in mature stems coincided with heavy lignification and suberisation of sclerenchyma sheath cell walls restricting apoplasmic tracer movement from the phloem to storage parenchyma apoplasms. Phloem unloading at this stage of stem development followed a symplasmic route linking sieve elements and storage parenchyma cells, as confirmed by the phloem-delivered symplasmic tracer, 8-hydroxypyrene-1,3,6-trisulfonic acid, moving radially from the stem phloem.

scholarly journals Localization of vicilin peptidohydrolase in the cotyledons of mung bean seedlings by immunofluorescence microscopy.

1978 ◽  
Vol 79 (1) ◽  
pp. 10-19 ◽  
Author(s):  
B Baumgartner ◽  
K T Tokuyasu ◽  
M J Chrispeels
Keyword(s):  
Vigna Radiata ◽  
Mung Bean ◽  
Immunofluorescence Microscopy ◽  
De Novo ◽  
Protein Bodies ◽  
Vascular Bundles ◽  
Large Protein ◽  
Parenchyma Cells ◽  
Storage Parenchyma ◽  
Monospecific Antibodies

Vicilin peptidohydrolase, the protease that hydrolyzes the reserve proteins in the cotyledons of mung bean (Vigna radiata) seedlings, has been localized intracellularly by immunofluorescence microscopy using monospecific antibodies against the enzyme and rhodamine-coupled goat-anti-rabbit immunoglobulin G's. The enzyme can first be visualized after 3 days of seedling growth and is associated with small foci within the cytoplasm of the storage parenchyma cells farthest from the vascular bundles. On the 4th day of growth, the protease is also present in the numerous large protein bodies within these cells. Vicilin peptidohydrolase is known to be synthesized de novo starting on the 3rd day of growth. Our observations are therefore consistent with the interpretation that the enzyme is synthesized in the cytoplasm and subsequently transported to the protein bodies.

Elemental Analysis of Phloem Tissue in Lemna Minor Root Tips

1980 ◽  
Vol 38 ◽  
pp. 798-799
Author(s):  
Patrick Echlin ◽  
Thomas Hayes ◽  
Clifford Lai ◽  
Greg Hook
Keyword(s):  
Vascular Tissue ◽  
Lemna Minor ◽  
Atomic Weight ◽  
Companion Cell ◽  
Root Tips ◽  
Phloem Tissue ◽  
Cell Stage ◽  
Phloem Parenchyma ◽  
Parenchyma Cells ◽  
Xylem Element

Studies (1—4) have shown that it is possible to distinguish different stages of phloem tissue differentiation in the developing roots of Lemna minor by examination in the transmission, scanning, and optical microscopes. A disorganized meristem, immediately behind the root-cap, gives rise to the vascular tissue, which consists of single central xylem element surrounded by a ring of phloem parenchyma cells. This ring of cells is first seen at the 4-5 cell stage, but increases to as many as 11 cells by repeated radial anticlinal divisions. At some point, usually at or shortly after the 8 cell stage, two phloem parenchyma cells located opposite each other on the ring of cells, undergo an unsynchronized, periclinal division to give rise to the sieve element and companion cell. Because of the limited number of cells involved, this developmental sequence offers a relatively simple system in which some of the factors underlying cell division and differentiation may be investigated, including the distribution of diffusible low atomic weight elements within individual cells of the phloem tissue.

The morphology of grain abscission in Zizania aquatica

1980 ◽  
Vol 58 (21) ◽  
pp. 2269-2273 ◽  
Author(s):  
H. B. Hanten ◽  
G. E. Ahlgren ◽  
J. B. Carlson
Keyword(s):  
Wild Rice ◽  
Cell Walls ◽  
Vascular Tissue ◽  
Embryo Sac ◽  
Middle Lamella ◽  
Abscission Zone ◽  
Rice Grains ◽  
Zizania Aquatica ◽  
Parenchyma Cells ◽  
Anatomical Evidence

The anatomical development of the abscission zone in grains of Zizania aquatica L. was correlated with development of the embryo. The abscission zone is well developed when the embryo sac is mature. Soon after pollination, the first anatomical evidence of abscission appears as plasmolysis of the separation layer parenchyma cells. This is followed by separation of the layers by dissolution of the middle lamella and fragmentation of cell walls. Persistence of intact vascular tissue and presence of a surrounding cone-shaped mass of lignified cells may be involved in abscission of wild rice grains.

scholarly journals Anatomy, Cell Wall Structure and Topochemistry of Water-Logged Archaeological wood aged 5,200 and 4,500 years

IAWA Journal ◽  
2008 ◽  
Vol 29 (1) ◽  
pp. 55-68 ◽  
Author(s):  
Katarina Čufar ◽  
Jožica Gričar ◽  
Martin Zupančič ◽  
Gerald Koch ◽  
Uwe Schmitt
Keyword(s):  
Cell Types ◽  
Wall Structure ◽  
Normal Wood ◽  
Uv Absorbance ◽  
Archaeological Wood ◽  
Transmission Electron ◽  
Parenchyma Cells ◽  
Prehistoric Settlements ◽  
And Storage ◽  
Uv Microspectrophotometry

Evaluating the state of deterioration of water-logged archaeological wood is necessary in order to select treatments for its conservation and storage, particularly in the case of valuable archaeological artefacts. For this purpose archaeological wood of ash (Fraxinus sp.) and oak (Quercus sp.) buried in water-logged conditions at prehistoric settlements on the Ljubljansko barje (Ljubljana moor), Slovenia, aged approx. 5,200 and 4,500 years, was investigated by means of light microscopy (LM), transmission electron microscopy (TEM) and cellular UV-microspectrophotometry (UMSP). LM and TEM revealed that the ash wood aged 5,200 years was the least preserved. The secondary walls of fibres, vessels and parenchyma cells were considerably thinner than in normal wood, indicating distinct degradation. TEM and UMSP additionally revealed strong delignification of the remaining parts of the secondary walls of all cell types. The compound middle lamellae appeared structurally intact, but had lower UV-absorbance than normal wood of the same species. The cell corners were topochemically unchanged, as shown by high analogue UV-absorbance. The UV-absorbance maxima at a wavelength of 278 nm corresponded to those of hardwood lignins. The oak heartwood was generally better preserved than the ash wood. Within each species, the 4,500- year-old samples generally appeared better preserved than those 5,200 years old.

Vacuole Proteins in Secondary Phloem Parenchyma Cells of Three Meliaceae Species

IAWA Journal ◽  
1991 ◽  
Vol 12 (1) ◽  
pp. 51-56 ◽  
Author(s):  
Ji-lin Wu ◽  
Bing-zhong Hao
Keyword(s):  
Enzymatic Digestion ◽  
Protein Bodies ◽  
Melia Azedarach ◽  
Bromophenol Blue ◽  
Secondary Phloem ◽  
Dense Granules ◽  
Phloem Parenchyma ◽  
Parenchyma Cells ◽  
Protein Nature ◽  
Blue Reaction

The secondary phloem in the trunk and branchlet of three species in Meliaceae, Swietenia macrophylla L., Chukrasia talularis A. Juss. and Melia azedarach L., was examined using light microscopy and electron microscopy. The vacuole protein bodies are found in most of the phloem parenchyma cells except companion cells. The protein nature of the bodies was demonstrated by the mercury - bromophenol blue reaction and enzymatic digestion with pepsin. Electronmicroscopical observations show that the protein bodies are electron-dense granules in central vacuoles. In the terminal branchlet, the protein bodies are extremely abundant before flushing in spring and most of them disappear in the inner phloem after flushing. This suggests that the vacuole protein bodies have a storage function.

Increased capacity for sucrose uptake leads to earlier onset of protein accumulation in developing pea seeds

2005 ◽  
Vol 32 (11) ◽  
pp. 997 ◽  
Author(s):  
Elke G. Rosche ◽  
Daniel Blackmore ◽  
Christina E. Offler ◽  
John W. Patrick
Keyword(s):  
Storage Protein ◽  
Protein Biosynthesis ◽  
Protein Bodies ◽  
Protein Accumulation ◽  
Sucrose Uptake ◽  
Wild Type ◽  
Protein Levels ◽  
Vicilin Gene ◽  
And Storage

Pea (Pisum sativum L.) cotyledons, overexpressing a potato sucrose transporter (StSUT1), were used to explore the hypothesis that sucrose stimulates the onset of storage protein biosynthesis. The study focused on the transition between pre-storage and storage phases of seed development. During this period supply of sucrose and hexose to transgenic cotyledons was unaffected by StSUT1 expression. However, protoplasmic levels of sucrose but not hexoses were elevated in transgenic cotyledons. Total protein levels in cotyledons followed the same temporal trend as observed for sucrose and this was reflected in an earlier appearance of protein bodies. Protein levels in wild type and StSUT1 cotyledons were found to lie on the same sucrose dose-response curve and this could be reproduced in vitro when wild type cotyledons were cultured on media containing various sucrose concentrations. Rates of [14C]sucrose uptake and incorporation into polymeric forms were consistent with protoplasmic sucrose supplying a proportion of the carbon skeletons required for storage protein accumulation. In addition, vicilin gene expression was up-regulated earlier in StSUT1 cotyledons. We conclude that sucrose functions both as a signal and fuel to stimulate storage protein accumulation and assembly into protein bodies. An earlier stimulation of storage protein synthesis is considered to largely account for the 14% increase in protein levels of StSUT1 seeds at harvest.

Differences in Water Relations Parameters for the Chlorenchyma and the Parenchyma of Opuntia ficus-indica Under Wet Versus Dry Conditions

1991 ◽  
Vol 18 (2) ◽  
pp. 95 ◽  
Author(s):  
G Goldstein ◽  
JL Andrade ◽  
PS Nobel
Keyword(s):  
Osmotic Pressure ◽  
Water Relations ◽  
Water Storage ◽  
Dry Weight ◽  
High Water ◽  
Opuntia Ficus Indica ◽  
Large Numbers ◽  
Parenchyma Cells ◽  
Storage Parenchyma ◽  
Dry Conditions

Water relations of the photosynthetic tissue (chlorenchyma) and of the water-storage parenchyma were studied for well watered and droughted Opuntia ficus-indica, a crassulacean acid metabolism plant cultivated worldwide for its fruits and cladodes. For well watered plants, die1 changes in osmotic pressure were evident in the chlorenchyma. Droughting the plants for 4 months resulted in a massive loss of water from the cladodes, particularly from the water-storage parenchyma, which could lose up to 82% of the water present at full turgor without irreversible tissue damage. Pressure-volume curves indicated a decrease in the osmotic pressure at full turgor of about 0.1 MPa for the water-storage parenchyma cells during drought; such a decrease of osmotically active solutes was consistent with the appearance of large numbers of starch grains. The bulk modulus of elasticity was 0.36 MPa for the water-storage parenchyma cells and 2.5-fold higher for the chlorenchyma cells, which were smaller with thicker cell walls than the former cells. Mucilage, a polysaccharide occurring extracellularly, constituted about 14% of the cladode dry weight; it could hold more than 30% of the total water content of the water-storage parenchyma. Polymerisation of sugars, large elastic cells in the water-storage parenchyma and mucilage with its high water-holding capacity helped maintain a positive turgor in the photosynthetic tissue, even after 4 months of drought.

Temporal and spatial expression of hexose transporters in developing tomato (Lycopersicon esculentum) fruit

2005 ◽  
Vol 32 (9) ◽  
pp. 777 ◽  
Author(s):  
Stephen J. Dibley ◽  
Michael L. Gear ◽  
Xiao Yang ◽  
Elke G. Rosche ◽  
Christina E. Offler ◽  
...  
Keyword(s):  
Lycopersicon Esculentum ◽  
Fruit Ripening ◽  
Tomato Fruit ◽  
Vascular Bundles ◽  
Hexose Transporter ◽  
Transporter Protein ◽  
Protein Levels ◽  
Parenchyma Cells ◽  
Storage Parenchyma ◽  
Post Transcriptional Regulation

Correlative physiological evidence suggests that membrane transport into storage parenchyma cells is a key step in determining hexose levels accumulated in tomato (Lycopersicon esculentum Mill.) fruit (Ruan et al. 1997). Expression of three previously identified hexose transporter genes (LeHT1, 2 and 3) demonstrated that LeHT3, and to a lesser extent LeHT1, are the predominant transporters expressed in young fruit (10 d after anthesis; DAA). Expression of both transporters dropped sharply until 24 DAA, after which only LeHT3 expression remained at detectable levels through to fruit ripening. LeHT2 was not expressed substantially until the onset of fruit ripening. For fruit at both 10 and 30 DAA, LeHT3 transcripts were detected in storage parenchyma cells of the outer pericarp tissue, but not in vascular bundles or the first layer of parenchyma cells surrounding these bundles. In contrast to LeHT gene expression, hexose transporter protein levels were maximal between 20 and 30 DAA, which corresponded to the period of highest hexose accumulation. The delayed appearance of transporter protein is consistent with some form of post-transcriptional regulation. Based on these analyses, LeHT3 appears to be responsible for the rapid hexose accumulation in developing tomato fruit.

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