• Applied Microscopy
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• v.31 no.4
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• pp.347-354
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• 2001

Immunoelectron microscopy of storage protein at early stage of seed development showed legumin was firstly accumulated protein in between endoplasmic reticulum (ER) cisternae, and these accumulates were differentiated into protein body (PB) by transformation at later stage. Thin sections of pea cotyledons during the later stages of seed maturation showed three morphologically different types of protein bodies. One of these, presented as rough-surfaced cisternae with terminal dilations, which contained protein deposits and were often found interdigitated between stacks of rough endoplasmic reticulum. Conventional electron microscopy at earlier stages of cotyledon development showed this protein body type initially developed from the rough ER. This transformation of endoplasmic reticulum into a protein body is believed to represent a new pathway of protein body development.

• Applied Microscopy
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• v.16 no.2
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• pp.49-60
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• 1986

Ultrastructures of the large and elongated cells (idioblasts) in the haustorium of a parasitic angiosperm, Cuscuta australis R. Brown growing on the host plant, Trifolium repens L. were investigated by the electron microscopy. The idioblasts were characterized by the presence of a large nucleus, small vacuoles, and dense cytoplasm including a number of various cell organelles such as ribosome, rough endoplasmic reticulum(r-ER), mitochondrion, dictyosome, proplastid, multilamellar structure(MLS), microfilament bundle(MFB), and cytosegresome. Therefore, it is suggested that the idioblasts are metabolical1y very active. Particularly, MLS, MFB, and cytosegresome observed in this study did not appear in the haustorial cells of the other parasitic angiosperms. MLS was transformed into vacuole and also incorporated with cell wall. MFB composed of microfilaments, about each 7.5 nm in diameter, was observed in nucleus and also cytoplasm. Some types of MFB were distinguished on the basis of arrangement of microfilaments. A part of cytoplasm sequestered by stacked cisternae of smooth ER(s-ER), cytosegresome, was altered into a vacuole which was formed by digestion of the sequestered cytoplasm and of cisternae of s-ER. Cell organelles such as MLS, MFB, and cytosegresome were discussed in relation to the metabolic control of the idioblasts.

• Journal of Plant Biology
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• v.37 no.3
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• pp.293-299
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• 1994

Developing rice endosperm cells display two morphologically distinct rough endoplasmic reticulum (ER) membranes, the cisternae ER (C-ER) and theprotein body ER (PB-ER), the latter delimiting the prolamine protein bodies. We (Li et al., 1993) have recently shown that the storage protein mRNAs are not randomly distributed on these ER types; the C-ER is enriched for glutelin mRNAs, whereas the PB-ER harbors predominantly prolamine transcripts. To address whether these ER types have differnet capacities to translate these mRNAs and translocate their proteins into the lumen, a microsomal fraction enriched in C-ER vesicles was prepared from devleoping rice seeds. When present in an in vitro translatin system, the microsomes were able to proteolytically remove the signal peptide and internalize both preproglutelin and preprolamine within the microsomal vesicles. Of the two species, preprolamine was more effectively translocated and processed. These results suggest that the C-ER has the capacity to recognize and bind both storage protein mRNAs during protein synthesis. Moreover, efficient translocation and processing of glutelin requires additional factors that are deficient or absent in the in vitro system.

• Proceedings of the Zoological Society Korea Conference
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• 1999.10b
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• pp.167.2-167
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• 1999

No Abstract, See Full Text

• Korean Journal of Animal Reproduction
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• v.16 no.1
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• pp.21-38
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• 1992

The present study was carried out to investigate morphologic changes in the corpus luteum of the pregnant rat by electron microscope after administration of prostaglandin F2$\alpha$(PGF2$\alpha$). Pregnant rates were treated with PGF2$\alpha$(1,500$\mu\textrm{g}$/rat) and their corpura lutea were observed morphologically. The results obtained in this study were summarized as follows ; 1. The weight of the ovaries and corpura lutea were decreased slightly at 8~24 hours after PGF2$\alpha$ administratin but no significant differences were observed. 2. The number of corpora lutea and luteal cells decreased slightly at 12~48 hours and 18~24 hours after PGF2$\alpha$ tretment but there were no signifciant differences between control and treatment. 3. The weight of uterus and the unmber of embryo decreased slightly at 96 hours and at 18~96 hours after PGF2$\alpha$ administration but no significant differences were obtained. 4. In the electron microscopic observatons, lipid droplets which are electron dense and appear in the cytoplasm moderately increased in number after PGF2$\alpha$ treatment. The lipid droplets were surrounded by mitochodria and appeared in the autophagic vacuoles. 5. Moderated and high electron dense mitochondria which are round or elongated in shape showed pleomorphism from 3 hours after PGF2$\alpha$ treatment. Destruction of tubular of vesicular cristae was observed at 6 hours after the treatment. Dense body and myelin figures in matrix of mitochondria were also appeared. 6. Well-developed smooth endoplasmic reticulum(sER) showed tubular or vesicular cisternae. A number of whorl membranes containing ribosomes, mitochondria and lipid droplets were observed at 1.5 hour after treatment. sER was abundant in luteal cells at 12 hours were treatment. 7. Well-developed Golgi pparatus appeared obviously 6 hours and more prominently at 12 hours. Those Golgi vesicles were remarkably dilated. 8. Generally, a few rough endoplasmic reticulum (rER) were appeared after treatment and cisternae showed slight dilatation. No differences among the treatments were observed. However, slight dilation of cisternae was observed at 1.5 hours after treatment. 9. Ribosomes composed of free and polyribosomes were abundant before treatment but polyribosomes were appeared at 12 to 24 hours after treatment. 10. Intercellular space were slightly extended at 3 hours and markedly extended at 12 hours. Numerous microvillous protrusions were observed at these times. Membranous multivesicular structures and autophagic vacuoles were also appeared in the intercellular space. 11. At 3 hours after the treatment, autophagic vacuoles appeared in the cytoplasm of the cell. They increased in number with time and were observed to transfer to the intercellular space. Lysosomal dense body appeared in the cytoplasm and the inclusion body was also observed in nucleus at 12 to 24 hours after treatment.

• Applied Microscopy
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• v.14 no.2
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• pp.15-28
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• 1984

The endosperm cells and the umbiliform layer of ginseng (Panax ginseng C.A. Meyer) seed are studied with light and electron microscope. Differentiated mitochondria, ER cisternae, proplastids and ribosomes are characteristically observed in the endosperm cells of matured seed. The cell inclusions contain the protein bodies and the spherosomes. Protein body contains, in proteinaceous matrix, globoids and crystalloids. Particularly the crystalloids have the lattice structure, and the formation of globoids is closely related with ER. Umbiliform layer has the positive reaction on alcian blue (pH 2.5) and the metachromasis on the toluidine blue. The umbiliform layer is formed by autolysis of endosperm cells, and composed of the deformated cell wall and the lipoprotein bodies. Particularly a part of the lipoprotein body and the fibrilar network structure have the positive reaction on acid phosphatase.

• Applied Microscopy
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• v.29 no.4
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• pp.499-509
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• 1999

Accumulations of the storage proteins in protein storage vacuole and the differentiation of protein bodies from protein-filled ER in developing pea cotyledons have been investigated using conventional and immunoelectron microscopy. To improve the fixation quality, single cells separated enzymatically from sliced cotyledons were used. At early stages of seed development osmiophilic protein accumulates in rER lumen were observed quite often. This protein-filled ER cisternae were differentiated into cytoplasmic protein bodies at late stage by the process called terminal dilations which have been considered a principal route of the formation of cytoplasmic protein bodies somewhat later in seed maturation. Immunocytochemical labellings of the vicilin and legumin show that presence of vicilin on both of the cytoplasmic PB and PD, but limited presence of legumin only on the cytoplasmic PB at intermediate stage of seed development. Immunogold labellings of Bip, ER retention protein, were observed on the inner periphery of protein deposits in protein storage vacuole. This result was regarded that Bip can recognize and retrieve misfolded protein during active accumulation of storage protein to the PD in PSV.

• The Korean Journal of Zoology
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• v.11 no.1
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• pp.5-12
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• 1968

The membrane structures were electron microscopically studied in the elongating lens fibers of the regenerating lens of adult Triturus pyrrhogaster. Observations were focused on the endoplasmic reticulum and mitochondria. The endoplasmic reticulum developed in the vicinity of the nucleus with active blebbing of the outer membrane. At the same time, the concentration of mitochondria around the rough-surfaced endoplasmic reticulum near by the nucleus was always observed. Both endoplasmic reticulum and mitochondrion undergo disintegration in the apical portion apart from the nucleus. Some considerations were discussed with reference to published data.

• Applied Microscopy
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• v.31 no.2
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• pp.199-206
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• 2001

In 1980s, the fragmentation or subdivision of protein deposits at the periphery of protein storage vacuole was suggested as the only route of PB development in pea cotyledon cells. Since then, other independant processes such as terminal dilation , transformation and de novo development have been discussed as alternative routes for PB development, and today, these multiple mechanisms of PB development are accepted as a result of active investigations. For analysis of the protein accumulations in the ER cisternae during seed development, immunocytochemical gold labellings were applyed on the single cells separated by enzymatic digestion from cotyledon tissue. Anti-legumin labellings at the early stage, and anti-vicilin labellings at the intermediate stage were observed on the protein-filled ER. The $\alpha-Tip$, which is the ER retention protein, was labelled somewhat at late stage, and PPase, a sort of tonoplast membrane protein, was labelled at early stage.

• Applied Microscopy
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• v.29 no.4
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• pp.451-457
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• 1999

Ultrastructure of adult Drosophila ocellus was compared with conventional electron microscopic method and osmium impregnation. When osmium impregnation was applied, some organelles of cells were strongly stained. Especially, subrhabdomeric cisternae (SRC) were strongly stained and showed network-iike structure as in compound eye. Other organelles including SSC, ER, nuclear envelope, pigment granules and mitochondria were also strongly stained. These organelles are known as a general calcium ion reservoir. In conclusion, the strong effect of light and shade by osmium impregnation was regarded as a result of strong binding between calcium ion and osmium tetroxide. Thus, we agree to the opinion that osmium impregnation is very useful methods to the comparative morphology of cell organelles.