• Journal of Yeungnam Medical Science
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• v.7 no.2
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• pp.27-37
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• 1990

To investigate the changing patterns of microfilament and microtubule arrangement and influence of myocardial cells and colchicine to microfilament and microtubule formation in cardiac endothelial cells the authors carried out indirect immunofluorescence stain for actin and tubulin with supernatant monoclonal antibodies. Secondary antibodies were IgG FITC conjugate. The results were summerized as follows. Fiberform reactions were stronger in the cells with many processes and spread cytoplasm and they became weaker after the endothelial cells formed monolayer. In the endothelial cells cocultured with myocardial cells the fiberform of the microtubule became less visible compared to control group but fiberform of the microtubule maintained strong intensity as endothelial cells formed monolayer. In the group treated with colchicine, there were no visible differences in microfilaments compared to control group but fiberform of microtubule revealed weaker intensity after colchicine treatment. The intensity of microtubule fiberform returned to control level after 2 days.

• Journal of Photoscience
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• v.9 no.2
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• pp.284-286
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• 2002

The inverted retina of the Onchidium dorsal eye (DE) is composed only of ciliary-type photoreceptor cells (CC's). The outer segment (OS) of the CC is a concentric lamellar structure consisting of many modified ciliary membranes and stains positively with anti-$\beta$-tubulin antibody. Near the base of the OS there are about 30 basal bodies each connecting individually to a cilium. The cilia are rod-shaped at the base, progressing upwards to a flattened sheet-like shape with increasing surface area. Three-dimensional analysis on serial sections demonstrates the ladle-shape of a modified cilium. Many modified cilia wrap around each other like the leaves of a cabbage. Nine pairs of microtubules (MT's) are located regularly in a ring at the base of the cilium, gradually losing their regular arrangement towards the periphery, where they separate into two subgroups that are contained within two swollen portions of a modified cilium. Within the CC of the Onchidium DE, MT's in the modified cilium exist as two poles extending longitudinally in a thin expanded ciliary membrane. This arrangement may support the photoreceptive OS and serve to maintain its structural integrity.

• ALGAE
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• v.22 no.4
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• pp.325-331
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• 2007

Cryptoglena pigra Ehrenberg from Korea was a photosynthetic euglenoid alga, which had typical characteristics of the Euglenales. The ultrastructure examination of C. pigra revealed certain features which were distinctly photosynthetic euglenoid: one U-shaped chloroplast with thylakoid membranes; two paramylon grains appressed to both sides of the chloroplast; eyespot associated with the chloroplast but not part of it. Three flagellar roots were associated with the two basal bodies. The four-membered dorsal root arose from the dorsal body and extended anteriorly following the reservoir membrane. At the base of the reservoir the dorsal band was nucleated by the dorsal root and it ran anteriorly between the reservoir membrane and eyespot. The dorsal band was continued with the microtubules of the canal and the pellicle. The singlet dorsal microtubules at the transition level arranged into doublets by a successive linkage of the existing adjacent microtubules, and the doublets rearranged into the cytoskeletal microtubules that were continuous with four microtubules in pellicles. Finally, the sixteen ridges gave rise to the pellicular ridges. The five to six-membered ventral root extended anteriorly into a cytoplasmic pocket through the reservoir and lined a cytoplasmic pocket.

• Journal of Plant Biology
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• v.39 no.4
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• pp.287-293
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• 1996

The effect of taxol and ethyl-N-phenylcarbamate (EPC) on the growth and gravitropism of maize roots and coleoptiles was studied. Taxol is known to promote the assembly of microtubules (MTs) and stabilizes MTs by preventing depolymerization. EPC, on the contrary, is an anti-microtubule drug that promotes disassembly of MTs. Taxol, at 1 $\mu$M, inhibited gravitropic response of maize roots to about 40%, but did not inhibit growth; at 10 $\mu$M, it inhibited the gravitropic response of coleoptile segments of maize by approximately 50%, but did not inhibit growth, while 0.5 mM EPC inhibited both the gravitropic response and growth of maize roots by approximately 50%. Taxol, which inhibited the gravitropic response of maize roots and coleoptile segments, had no effect on either the polar or the bilateral transport of auxin. These results indicated that MT polymerization could not occur normally with taxol or EPC, so that if there was any abnormal rearrangement of MT, the gravitropic response was inhibited, which resulted from the inhibition of neither growth nor auxin transport. This results suggested that gravitropic response was related to the MT arrangement, and that both straight growth and the differential growth in gravitropic response could be regulated by different mechanisms.

• Applied Microscopy
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• v.31 no.3
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• pp.245-256
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• 2001

The morphological characteristics of spermatogenic cells during the spermiogenesis of Paradoxornis webbiana were studied by transmission electron microscope. Spermiogenesis of P. webbiana was divided into ten phase. The chromatin granules became fibrous granules at the Golgi phase, gradually condensed at the cap phases, condensed as a stick at the acrosomal phase, and finally, a perfect nucleus was formed at the maturation phase. The formation of sperm tail began at the early Golgi phase, and completed at the late maturation phase. In particular, the dense materials existed in the sperm neck, which is wedged between the tip of segmented columns and the first mitochondria of the middle piece. The axone in the neck were surrounded by the dense materials. The axonema in spermatozoon contains a 9+2 arrangement of microtubules: 9 doublets, and 2 central single microtubules. Mitochondrial bundles of middle piece were composed of a pair of arms, which surrounded the axone of the middle piece by the $15^{\circ}$ angled-helical structure. The outer membrane of mitochondria were surrounded by microtubules in plasma membrane of the sperm. The undulating membrane had a helical structure, and the sperm plasma membrane was surrounded by undulating membrane.

• Journal of Life Science
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• v.25 no.11
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• pp.1223-1229
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• 2015

Oryzalin is a dinitroaniline herbicide, which disrupts the arrangement of microtubules. Microtubules and microfilaments are cytoskeletal components that are thought to play a role in the sedimentation of statoliths and the formation of cell walls. Statoliths regulate the perception of gravity by columella cells in the root tip. To determine the effect of oryzalin on the gravitropic response, ethylene production in primary roots of maize was investigated. Treatment with 10^-4 M oryzalin to the root tip inhibited the growth and gravitropic response of the roots. However, the treatment had no effect on the elongation zone of the roots. An application of 10^-4 M oryzalin for 15 hr to the root tip caused root tip swelling. The application of 1-aminocycopropane-1-carboxylic acid (ACC), a precursor of ethylene, to the root tip also inhibited the gravitropic response. To understand the role of oryzalin in the regulation of the growth and gravitropic response of roots, ethylene production in the primary roots of maize was measured following treatment with oryzalin. Oryzalin stimulated ethylene production via the activation of ACC oxidase (ACO) and ACC synthase (ACS), and it increased the expression of ACO and ACS genes. Indole-3-acetic acid (IAA) played a key role in the asymmetric elongation rates observed during gravitropism. The results suggest that oryzalin alters the gravitropic response of maize roots through modification of the arrangement of microtubules. This might reduce the distribution of IAA in the upper and lower sides of the elongation zone and increase ethylene production, thereby inhibiting growth and gravitropic responses.