Structural Aspects of Protein Accumulation in Developing Pea Cotyledons. I. Qualitative and Quantitative Changes in Parenchyma Cell Vacuoles

1979 ◽  
Vol 6 (1) ◽  
pp. 81 ◽  
Author(s):  
S Craig ◽  
DJ Goodchild ◽  
AR Hardham
Keyword(s):  
Cell Volume ◽  
Surface Area ◽  
Structural Changes ◽  
Light And Electron Microscopy ◽  
Parenchyma Cell ◽  
Protein Body ◽  
Average Diameter ◽  
Protein Bodies ◽  
Protein Accumulation ◽  
Parenchyma Cells

Structural changes in pea cotyledons during development were studied using light and electron microscopy. Changes in the vacuolar system and cytoplasm of cotyledon parenchyma cells, during the period of storage protein deposition, are reported. Eight days after flowering, the parenchyma cells each contain one or two large vacuoles that are replaced by progressively smaller vacuoles during the next 10 days of development. Stainable material that can be histochemically identified as protein appears on the inner surface of the vacuole tonoplast 8 days after flowering. These vacuoles become smaller and more frequent during development and the amount of proteinaceous material within each vacuole increases until, at days 16-20 after flowering, they become densely packed with protein and are described as protein bodies. At day 8, the vacuole(s) have an average diameter of 39 �m, an average volume of 41 000 �m� , representing 75 % of the cell volume, and a surface area of 5500 �m�. By day 20, the average protein body diameter has fallen to 1 �m. There are, however, approx. 175 000 such protein bodies per cell, occupying 91 500 �m� or approx. 20 % of the cell volume, and whose total surface area is 550 000 �m�. The surface to volume ratlo of the vacuole/protein bodies Increases 55 times between days 8 and 20. Apart from this increase in surface area available for possible entry of protein, no mechanism for such entry can be suggested from our nlicrographs.

Structural Aspects of Protein Accumulation in Developing Pea Cotyledons. III. Immunocytochemical Localization of Legumin and Vicilin Using Antibodies Shown to Be Specific by the Enzyme-Linked Immunosorbent Assay (ELISA)

1980 ◽  
Vol 7 (3) ◽  
pp. 339 ◽  
Author(s):  
S Craig ◽  
A Millerd ◽  
DJ Goodchild
Keyword(s):  
Immunosorbent Assay ◽  
Storage Proteins ◽  
Protein Body ◽  
Protein Bodies ◽  
Enzyme Linked Immunosorbent Assay ◽  
Protein Accumulation ◽  
Immunocytochemical Localization ◽  
Elisa Technique ◽  
Immunocytochemical Techniques ◽  
Structural Aspects

The site of sequestration of the storage proteins legumin and vicilin during development of cotyledons from pea (Pisum sativum L.) has been determined using improved immunocytochemical techniques. Antibodies to legumin and vicilin were made monospecific by affinity chromatography. They were allowed to react on sections of glycol methacrylate-embedded cotyledon tissue and detected by indirect immunocytochemical localization using rhodamine-labelled antibodies. The enzyme-linked immunosorbent assay (ELISA) technique was adapted to verify antibody specificity at a sensitivity up to 300 times greater than that of immunodiffusion. Legumin and vicilin 4 are localized in small peripheral deposits within large vacuoles as early as day 8 after flowering. As the vacuoles fragment during development the storage proteins continue to be localized in the vacuolar deposits until, at day 16, they entirely fill vacuoles, now termed protein bodies. Thereafter, the protein bodies become more densely packed and retain a similar form from day 22 to maturity. Wherever the same vacuolar deposit of protein body could be observed in adjacent sections, antilegumin and antivicilin 4 labelled both deposits, clearly indicating that both storage proteins are sequestered into the same area of protein.

Structural Aspects of Protein Accumulation in Developing Pea Cotyledons. II. Three-Dimensional Reconstructions of Vacuoles and Protein Bodies From Serial Sections

1980 ◽  
Vol 7 (3) ◽  
pp. 329 ◽  
Author(s):  
S Craig ◽  
DJ Goodchild ◽  
C Miller
Keyword(s):  
Three Dimensional ◽  
Protein Body ◽  
Protein Bodies ◽  
Dimensional Structure ◽  
Protein Accumulation ◽  
Serial Sections ◽  
Seed Maturity ◽  
Spherical Structures ◽  
A Cell ◽  
Structural Aspects

The three-dimensional structure of vacuoles and protein bodies seen in developing cotyledons from pea (Pisum sativum L.) have been reconstructed from serial sections. At days 12 and 15 after flowering, serial sections 1 �m thick of epoxy-embedded seed tissue were used to determine vacuole morphology while, at day 20, serial sections 0.25 �m thick were examined by electron microscopy to ascertain protein body morphology. At day 12 there are one or two large vacuoles having extremely complex protrusions emanating from a larger central vacuolar volume. This gives rise to up to 20 apparently discrete vacuole profiles in a given section through a cell. By day 15, there are many smaller, approximately spherical, vacuoles and also some that are more complex. At day 20 most protein bodies are discrete, spherical structures, although a few irregularly shaped bodies are seen. The results support the concept of a large highly convoluted central vacuole fragmenting to give rise to the protein bodies seen towards seed maturity.

Phytochrome-induced structural changes and protein degradation prior to radicle protrusion in Datura ferox seeds

1995 ◽  
Vol 73 (9) ◽  
pp. 1371-1378 ◽  
Author(s):  
R. A. Mella ◽  
R. A. Sànchez ◽  
S. Maldonado
Keyword(s):  
Protein Degradation ◽  
Protein Content ◽  
Structural Changes ◽  
Red Light ◽  
Light And Electron Microscopy ◽  
Protein Bodies ◽  
Embryonic Axes ◽  
Radicle Protrusion ◽  
Micropylar Endosperm ◽  
Extensive Degradation

In Datura ferox L. seeds induced to germinate by the far-red light absorbing form of phytochrome (Pfr) and alternating temperatures, protein degradation started before radicle protrusion. Proteolysis was, however, restricted to the micropylar region of the endosperm in which the protein content decreased 51% by 48 h after red light treatment. There was no change during that time in the protein content of the rest of the endosperm or in the embryo. Light and electron microscopy preparations show the vacuolation of protein bodies along with other changes in cellular structure in the micropylar portion of the endosperm in seeds treated with red light (R). No changes were detected in the rest of the endosperm or in the micropylar portions of far-red light (FR) treated seeds. In the embryonic axes there were some alterations but only in a small sector of the calyptra. In contrast, shortly after radicle protrusion (5 h), there was extensive degradation of protein bodies in the embryonic axes. A Pfr is required for the induction of protein degradation in the micropylar portion of the endosperm in the intact seed before radicle protrusion. Incubation of isolated micropylar portions induced protein degradation in tissues from seeds treated with either R or FR. The results do not support a source–sink type of control of protein degradation in the endosperm driven by the beginning of embryo growth but suggest the participation of regulatory signals in the determination of a temporal and spatial pattern of protein degradation in both the endosperm and the embryo. Key words: germination, dormancy, phytochrome, protein degradation, micropylar endosperm.

Estructura del cotiledón de la semilla de almendra (Prunus amygdalus L.) cruda, remoj ada y tostada / Cotyledon structure of raw, soaked and roasted almond (Prunus amygdalus L.)

1998 ◽  
Vol 4 (3) ◽  
pp. 189-197 ◽  
Author(s):  
M.J. Pascual-Albero ◽  
I. Pérez-Munuera ◽  
M.A. Lluch
Keyword(s):  
Parenchyma Cell ◽  
Middle Lamella ◽  
Cell Junctions ◽  
Protein Bodies ◽  
Lipid Bodies ◽  
Cellular Organization ◽  
Prunus Amygdalus ◽  
Significant Modification ◽  
Parenchyma Cells ◽  
Scanning Electron

The microstructure of the sweet almond (variety Marcona) and the most important microstruc tural changes caused after roasting (150 °C, 45 min) and soaking (H2O and NaCl 5%, 24 h) were studied by scanning electron microscopy (SEM). The majority of the cotyledon tissue is made up of rather large, nearly isodiametric parenchyma cells with a thick cell wall; the cell-to-cell junc tions are characterized by a distinct middle lamella. The cytoplasmatic membrane delimits the cellular content, protein bodies and lipid bodies being the major components. A cytoplasmic network consisting of the membranous system structured as hexagonal cells extends throughout each parenchyma cell, and surrounds the major components. The parenchymatic tissue is surrounded by a layer of epidermic cells and tegument. After roasting, the cellular organization is lost and the cytoplasmic network surrounding the lipid bodies and protein bodies is altered; the heat destroys some middle lamellae of cell-to-cell junctions; the cytoplasmic compartimental ization of the oil is lost in most cells and the oil drops coalesce; protein bodies are distended and aggregated; other thermal modifications of roasting included pitting and pock-marking of the epidermis and protein bodies, caused by the escape of steam and oil. Soaking in water did not cause drastic changes in the structure; the most significant modification was an alteration of the cytoplasmic network and membrane; soaking in 5% NaCl also produced a partial disolution of protein bodies.

Endosperm Morphology and Protein Body Formation in Developing Wheat Grain

1981 ◽  
Vol 8 (1) ◽  
pp. 5 ◽  
Author(s):  
WP Campbell ◽  
JW Lee ◽  
TP O'brien ◽  
MG Smart
Keyword(s):  
Endoplasmic Reticulum ◽  
Culture Medium ◽  
Sucrose Concentration ◽  
Light And Electron Microscopy ◽  
Starch Synthesis ◽  
Protein Body ◽  
Protein Bodies ◽  
Wheat Grain ◽  
Body Formation ◽  
Intact Plants

The development of wheat grain from intact plants and from detached ears growing in culture has been studied by light and electron microscopy. Provided the sucrose concentration was at a level sufficient to maintain a normal rate of starch synthesis, the endosperm morphology of grain from cultured ears was essentially identical to that of endosperm from intact plants. If, however, sucrose concentration in the culture medium was very low (0.25%), some morphological abnormalities occurred in the endosperm near the crease and adjacent to the seed coat. The synthesis of storage protein in the endosperm is believed to occur largely on polyribosomes attached to endoplasmic reticulum even at the earliest stages of development. Protein bodies are always surrounded by a single membrane, the origin of which may vary. Some protein bodies arise by distention of the endoplasmic reticulum and clearly the membrane here represents the sac into which the protein is discharged after synthesis. In other cases the bounding membrane may be that of a true vacuole or it may be dictyosomal in origin. The methods by which it is suggested that protein bodies are formed in wheat endosperm have parallels in other seeds, although there are some significant differences.

Thin-section, freeze-fracture, and energy dispersive x-ray analysis studies of the protein bodies of tomato seeds

1980 ◽  
Vol 58 (6) ◽  
pp. 699-711 ◽  
Author(s):  
Ernest Spitzer ◽  
John N. A. Lott
Keyword(s):  
Freeze Fracture ◽  
Protein Body ◽  
Cell Types ◽  
Energy Dispersive ◽  
Protein Bodies ◽  
Elemental Content ◽  
Tomato Seed ◽  
Endosperm Tissue ◽  
X Ray ◽  
Edx Analysis

Protein bodies of dry seeds of tomato (Lycopersicon esculentum) from radicle, hypocotyl, cotyledon, and endosperm tissue were extensively studied using thin-sectioning, freeze-fracturing and energy dispersive x-ray (EDX) analysis. Protein bodies varied in size, were oval to circular in section, and generally consisted of a proteinaceous matrix, globoid crystal, and protein crystalloid components. Size, shape, and arrangements of globoid crystals and protein crystalloids varied even within the same cell. Globoid crystals were generally oval to circular in section. They were always surrounded by a proteinaceous matrix. In a given protein body the number present ranged from a few to numerous. A protein body generally contained only one protein crystalloid. In section, protein crystalloids were irregular or angular in shape. They were composed of substructural particles which formed lattice planes. EDX analysis of tomato seed globoid crystals revealed the presence of P, K, and Mg in all cases, a fact that is consistent with globoid crystals being phytin-rich. Rarely, small amounts of calcium were found along with P, K, and Mg in globoid crystals of each of the tissue regions considered. The distribution pattern of cells with Ca containing globoid crystals was random. Small amounts of Fe and Mn were also found in the globoid crystals of protein bodies from certain cell types. These two elements, unlike calcium, were specific in terms of their distribution. Globoid crystals from the protodermal cells often contained Mn and Fe. The globoid crystals from provascular tissue of radicle, hypocotyl, and cotyledon regions often contained Fe while globoid crystals in the first layer of large cells surrounding these provascular areas always contained Fe. Results from EDX analysis of the proteinaceous material from the protein bodies are presented and discussed as are variations in elemental content due to different fixations.

An Ultrastructural and Radio-Autographic Study of the Evolution of the Interphase Nucleus in Plant Meristematic Cells (Allium Porrum)

1974 ◽  
Vol 14 (2) ◽  
pp. 263-287
Author(s):  
J. G. LAFONTAINE ◽  
A. LORD
Keyword(s):  
Interphase Nucleus ◽  
Structural Changes ◽  
Tritiated Thymidine ◽  
Light And Electron Microscopy ◽  
Allium Porrum ◽  
Meristematic Cells ◽  
Fibrillar Material ◽  
Nuclear Structures ◽  
S Period ◽  
Dense Chromatin

Radioautography under both light and electron microscopy was exploited to investigate the structural changes of the chromatin reticulum which characterizes the interphase nucleus of a number of plants. Allium porrum meristematic plant cells were used for this purpose. In this species, the telophase chromosomes uncoil into dense strands which, during the G1 period, gradually give rise to a coarse reticulum. There then follows an extensive unravelling of portions of these strands, and high-resolution radioautography reveals that labelling with tritiated thymidine predominantly occurs over zones of the nucleus consisting of diffuse fine fibrillar material. As the S-period progresses, a chromatin reticulum reappears throughout the nuclear cavity, the tortuous strands being approximately 0.25 µm in diameter. Most of the radioautographic grains still remain over the light nucleoplasmic areas but a number of these are now located on the outermost portion of the dense chromatin profiles. By the end of the S-period, the chromatin strands are slightly thicker (ca. 0.3 µm) and form a looser reticulum. Labelling has decreased noticeably in nuclei of that period, the radioautographic grains being grouped into clusters resting over more or less spherical regions of the chromatin reticulum. Judging from their localization at the surface of the nucleolus or close to the nuclear envelope, these structures correspond to chromocentres. The additional interesting finding that such nuclear structures appear much less compactly organized strongly suggests that chromocentres undergo important conformational modifications during duplication of their DNA.

Cerebral autosomo-dominant arteriopathy with subcortical infarctions and leukoencephalopathy

2021 ◽  
Vol 26 (5) ◽  
pp. 30-38
Author(s):  
E. A. Savchuk ◽  
E. P. Golubinskaya ◽  
T. N. Shcherbinina ◽  
G. Yu. Voronin ◽  
E. O. Savchuk ◽  
...  
Keyword(s):  
Clinical Case ◽  
Structural Changes ◽  
Light And Electron Microscopy ◽  
Joint Work ◽  
Genetic Studies ◽  
Small Vessels ◽  
Clinical Case Study ◽  
The Family ◽  
Probable Diagnosis

The article presents an analysis of the literature and a clinical case of a rare disease from the group of diseases of small vessels — cerebral autosomal dominant arteriopathy with subcortical infarction and leukoencephalopathy (CADASIL).It is based on the deposition of osmiophilic granulation material in vessels of small and medium caliber. A mutation in the NOTCH3 gene on chromosome 19p13 leads to significant structural changes in the walls of small arteries due to impaired differentiation and maturation of smooth muscle cells.CADASIL is characterized by four key symptoms: migraines, recurrent ischemic strokes, mental disorders, and cognitive decline. The clinical case study is presented from the standpoint of a multidisciplinary patient-oriented approach of joint work of neurologists and morphologists. On the basis of clinical and laboratory criteria, a probable diagnosis was made. To confirm it, a muscle biopsy was performed (a musculocutaneous flap from the inner surface of the thighs and forearms), in order to conduct light and electron microscopy. The details of the results of the morphological study, which made it possible to verify the patient’s diagnosis, are presented. Differential diagnostic judgments are presented and recommendations for genetic studies in the family, prognosis and treatment of the patient are given.

Functional medial thickening and folding of the internal elastic lamina in coronary spasm

2011 ◽  
Vol 300 (2) ◽  
pp. H423-H430 ◽  
Author(s):  
Yasumi Uchida ◽  
Yasuto Uchida ◽  
Akimasa Matsuyama ◽  
Atsushi Koga ◽  
Yuko Maezawa ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Structural Changes ◽  
Light And Electron Microscopy ◽  
Coronary Spasm ◽  
Cellular Level ◽  
Internal Elastic Lamina ◽  
Circular Smooth Muscle ◽  
The Media ◽  
Medial Thickening ◽  
Elastic Lamina

Although there are a number of studies on vasospastic angina, the structural changes at the cellular level that occur in the coronary arterial wall during spasm are not well known. Coronary spasm was induced by brushing the coronary adventitia in nine anesthetized beagles, and structural changes in the spastic coronary segments were examined by light and electron microscopy, making comparisons with the adjacent nonspastic segments. The % diameter stenosis of the spastic segments as measured angiographically was 79.4 ± 12% (mean ± SD). Light microscopic changes in the spastic and nonspastic segments were as follows: medial thickness 1,512 vs. 392 μm ( P < 0.0001) and % diameter and % area stenoses of spastic segment 81.0% and 96.5%, respectively, indicating that spasm was induced by medial thickening. Circular smooth muscle cells (SMCs) in the media were arranged in parallel with the internal (IEL) and external (EEL) elastic lamina in nonspastic segments but radially rearranged in spastic segments. SMCs were classified by their patterns of connection to IEL into six types by electron microscopy. Of these, three contracted and pulled the IEL toward the EEL, causing folding of the IEL and waving of EEL resulting in thickening of the media and narrowing of the lumen. We conclude that coronary spasm was elicited by radial rearrangement of the medial SMCs due to their own contraction and resultant medial thickening and folding of IEL, creating a piston effect to narrow the lumen, i.e., spasm.

SUPPRESSION OF SUPERCONDUCTIVITY AND STRUCTURAL CHANGES IN R1-xPrxBa2Cu3O7-y (R=Sm, Gd, Er, Tm, Y)

1992 ◽  
Vol 06 (16n17) ◽  
pp. 1069-1074 ◽  
Author(s):  
P. LIU ◽  
W. J. ZHU ◽  
J. L. ZHANG ◽  
S. Q. GUO ◽  
S. L. JIA ◽  
...  
Keyword(s):  
Transition Temperature ◽  
Cell Volume ◽  
Superconducting Transition Temperature ◽  
Unit Cell Volume ◽  
Structural Changes ◽  
Unit Cell ◽  
Superconducting Transition ◽  
Lattice Constants

The compounds R 1-x Pr x Ba 2 Cu 3 O 7-y ( R = Sm , Gd , Er , Tm and Y ) have been prepared and examined for superconductivity and structural changes. It is observed that the superconducting transition temperature Tc of R 1-x Pr x Ba 2 Cu 3 O 7-y decreases monotonically with increasing Pr concentration for all systems. At constant Pr concentration, Tc decreases approximately linearly with increasing radius with R cations while the lattice constants a,b,c and unit cell volume V increase. The correlation of both the Tc and the lattice constants with the radius of R cations is the same as for 1:2:4, 2:4:7, and 1:2:1:2 compounds.

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