• Journal of Plant Biology
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• v.37 no.2
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• pp.195-201
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• 1994

In order to study the effects of polyamine inhibitors and polyamines on adventitious root formation, the correlation between adventitious root formation and carbohydrate metabolism was investigated in inoculated soybean (Glycine max L.) cotyledons at the concentration of $10^{-3}\;M$ methylglyoxal bis-(guanylhydrazone)[MGBG], and $10^{-3}\;M$ MGBG plus $10^{-5}\;M$ polyamines (putrescine, spermidine and spermine), respectively, for the adventitious root formation medium. The contents of starch, maltose and sucrose were lower in control and were higher in the treatments containing $10^{-3}\;M$ MGBG, and $10^{-3}\;M$ MGBG plus $10^{-5}\;M$ polyamines during culture. It was shown that the soluble sugar levels, except glucose, were higher than that of control in most of the treatments and the change in glucose contents tended to be similar to that control. The amylase activity increased in control and MGBG treatment, the maltase activity was higher in control and the invertase activity showed less substantial changes during culture.ulture.

• Korean Journal of Plant Tissue Culture
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• v.21 no.2
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• pp.105-110
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• 1994

In order to study on the effect of polyamine inhibitors and polyamines on adventitious root formation the correlation between adventitious root formation and polyamine levels were investigated in cultured soybean (Glycine max L.) cotyledons. Adventitious root formation was inhibited in medium containing 10$^{-4}$ -10/ sup -2/ M polyamine inhibition such as $\alpha$-difluoromethylornithine (DFMO), $\alpha$-difluoromethylarginine (DFMA), cyclohexylammonium sulfate (CHA), dicyclohexyl-amine (DCHA) and methylglyoxal-bis (guanylhydrazone) (MGBG). An inhibitory effects at 10$^{-3}$ M MCBG were much higher than other treatments. Treatment with 10$^{-3}$ M MGBG plus 10$^{-5}$ M spermine led to reversal of the effects of MGBG alone. The polyamine levels were sharply increased in the first few days in each treatnent compared to control. The remarkably increasing polyamine contents were observed in medium supplemented spermine.

• Korean Journal of Medicinal Crop Science
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• v.5 no.1
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• pp.7-13
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• 1997

Calli induced from the leaf segment of Bupleurum falcatum were cultured on Mu-rashige and Skoog's(MS) medium supplemented with 2, 4-D, IBA, IAA and NAA of 0.1 mg/l , The induction of adventitious roots from callus was the best in MS medium supplemented with 0.1 mg/l 2, 4-D and the lateral root was the same. The pretreatment of 0.1 mg/l 2, 4-D for 120 hours was most effective for the formation and grwoth of adventitious roots. The number of adventitious roots per micro callus pre-treated with 0.1 mg/l 2, 4- D was 5. 3 which was the highest level. The callus subcultured for 4 weeks were best for the adventitious root formation. The callus subcultured for more than 4 weeks decreased the adventitious root formation and turned to brown in color.

• Restorative Dentistry and Endodontics
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• v.46 no.2
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• pp.17.1-17.9
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• 2021

Objectives: In recent in vitro study, it was reported that osteostatin (OST) has an odontogenic effect and synergistic effect with mineral trioxide aggregate (MTA) in human dental pulp cells. Therefore, the aim of this study was to evaluate whether OST has a synergistic effect with MTA on hard tissue formation in vivo. Materials and Methods: Thirty-two maxillary molars of Spraque-Dawley rats were used in this study. An occlusal cavity was prepared and the exposed pulps were randomly divided into 3 groups: group 1 (control; ProRoot MTA), group 2 (OST 100 μM + ProRoot MTA), group 3 (OST 10 mM + ProRoot MTA). Exposed pulps were capped with each material and cavities were restored with resin modified glass ionomer. The animals were sacrificed after 4 weeks. All harvested teeth were scanned with micro-computed tomography (CT). The samples were prepared and hard tissue formation was evaluated histologically. For immunohistochemical analysis, the specimens were sectioned and incubated with primary antibodies against dentin sialoprotein (DSP). Results: In the micro-CT analysis, it is revealed that OST with ProRoot MTA groups showed more mineralized bridge than the control (p < 0.05). In the H&E staining, it is showed that more quantity of the mineralized dentin bridge was formed in the OST with ProRoot MTA group compared to the control (p < 0.05). In all groups, DSP was expressed in newly formed reparative dentin area. Conclusions: OST can be a supplementary pulp capping material when used with MTA to make synergistic effect in hard tissue formation.

• Journal of Ginseng Research
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• v.48 no.2
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• pp.220-228
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• 2024

Background: Panax ginseng, one of the valuable perennial medicinal plants, stores numerous pharmacological substrates in its storage roots. Given its perennial growth habit, organ regeneration occurs each year, and cambium stem cell activity is necessary for secondary growth and storage root formation. Cytokinin (CK) is a phytohormone involved in the maintenance of meristematic cells for the development of storage organs; however, its physiological role in storage-root secondary growth remains unknown. Methods: Exogenous CK was repeatedly applied to P. ginseng, and morphological and histological changes were observed. RNA-seq analysis was used to elucidate the transcriptional network of CK that regulates P. ginseng growth and development. The HISTIDINE KINASE 3 (PgHK3) and RESPONSE REGULATOR 2 (PgRR2) genes were cloned in P. ginseng and functionally analyzed in Arabidopsis as a two-component system involved in CK signaling. Results: Phenotypic and histological analyses showed that CK increased cambium activity and dormant axillary bud formation in P. ginseng, thus promoting storage-root secondary growth and bud formation. The evolutionarily conserved two-component signaling pathways in P. ginseng were sufficient to restore CK signaling in the Arabidopsis ahk2/3 double mutant and rescue its growth defects. Finally, RNA-seq analysis of CK-treated P. ginseng roots revealed that plant-type cell wall biogenesis-related genes are tightly connected with mitotic cell division, cytokinesis, and auxin signaling to regulate CK-mediated P. ginseng development. Conclusion: Overall, we identified the CK signaling-related two-component systems and their physiological role in P. ginseng. This scientific information has the potential to significantly improve the field-cultivation and biotechnology-based breeding of ginseng.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.3
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• pp.576-583
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• 2005

Tooth formation is a complex developmental process that is mediated through a series of reciprocal epithelial-mesenchymal interactions. Several signal pathways and transcription factors have been implicated in regulating molar crown development, but relatively little is known about the regulation of root development. It was reported that NFI-C knockout mice showed abnormal root formation with normal crown. The aims of this study are to elucidate how the NFI-C regulate the determine of root shape and odontoblasts differentiation. We carried out immunohistochemistry using cytokeratin to investigate the role of Hertwig's epithelial root sheath and DSPP mRNA in-situ hybridization to conform the nature of root dentin during root development in NFI-C knockout mice. Cytokeratin reacted with all the HERS cells and the continuity of cytokeratin positive cells between the HERS cells and enamel epithelium was lost in the cervical region both wild and K/O types. After root dentin deposition cytokeratin positive-HERS cells showed irregularity and loss of polarity in the cervical region in K/O type. DSPP mRNA was strongly expressed in odontoblasts of crown and root dentin in wild type mice, whereas expression of DSPP mRNA was restricted in odontoblast of crown dentin in the K/O type. During root formation in NFI-C knockout mice, HERS normally grow out of the crown but fail to induce odontoblast differentiation in root portion. These results suggest that NFI-C may play important roles in odontoblast differentiation during root dentin formation.

• Korean Journal of Medicinal Crop Science
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• v.14 no.4
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• pp.225-228
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• 2006

To acquire the normal regeneration of plantlets, we investigated combinations and concentrations of plant growth regulations for optimal conditions of adventitious root formation. Based on the previous study, we performed callus and shoot induction. When induced shoot was transferred into a rooting medium containing plant hormones, it wilted and died. Thus, the shoot proliferated on 1/2 MS medium for 10 days and was then treated with MS medium supplemented with 3.0 mg/L NAA for 3 days. Adventitious root formations were observed after shoot planlets were transferred to 1/3 MS medium. The concentrations of salt and sucrose were gradually reduced in MS medium and the rooted plantlets were transferred for acclimatization into a mixture of peatmoos : perlite (3 : 2).

• Plant Resources
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• v.7 no.1
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• pp.60-64
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• 2004

The establishment of an efficient protocol for plant regeneration and micropropagation from leaf explant cultures of Chicory, Cichorium intybus L. var. sativus. is reported. Callus formation rate appeared 100% from explant in all growth regulators, but calli formed in the prensence of naphthaleneacetic acid (NAA) were appeared very compact and non-embryogenic state. The regenerated shoots were obtained from leaf explant cultures on solid MS medium containing different concentrations of cytokinins and auxin. The highest number of shoots (5.7) per explant and shoot growth (2.8cm) was obtained on MS medium containing 0.1 mg BAP L$^{-1}$ and 0.1 mg NAA L$^{-1}$ . Indole acetic acid was the most suitable auxin for root formation among three auxins tested. 2,4-D had no effect on shoot and root formation.

• The korean journal of orthodontics
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• v.24 no.3 s.46
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• pp.621-630
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• 1994

The purpose of this study was to evaluate root resorption and alveolar bone resorption pattern by jiggling movement. 16 adult cats were divided into 4 groups(6, 12, 18, 24 days). In test side, mesio-distal jiggling force was applied in right maxillary 1st premolar in 3 days cycle In control side, mesial force was applied in left maxillary 1st premolar. Radiographic and histologic observation were performed in 6, 12, 18, 24 days after force application. The results were as follow: 1. Alveolar bone resorption was more severe by jiggling force than by unidirectional force. 2. Root resorption pattern was not different between jiggling force and unidirectional force. 3. Combined pattern of bone resorption and new bone formation appeared in jiggling group. 4. New bone formation began to appear at periapical area of jiggling group after 24 days, because alveolar bone resorption was severe and extrusion resulted.

• Molecules and Cells
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• v.44 no.11
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• pp.830-842
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• 2021

When perceiving microbe-associated molecular patterns (MAMPs) or plant-derived damage-associated molecular patterns (DAMPs), plants alter their root growth and development by displaying a reduction in the root length and the formation of root hairs and lateral roots. The exogenous application of a MAMP peptide, flg22, was shown to affect root growth by suppressing meristem activity. In addition to MAMPs, the DAMP peptide PEP1 suppresses root growth while also promoting root hair formation. However, the question of whether and how these elicitor peptides affect the development of the vascular system in the root has not been explored. The cellular receptors of PEP1, PEPR1 and PEPR2 are highly expressed in the root vascular system, while the receptors of flg22 (FLS2) and elf18 (EFR) are not. Consistent with the expression patterns of PEP1 receptors, we found that exogenously applied PEP1 has a strong impact on the division of stele cells, leading to a reduction of these cells. We also observed the alteration in the number and organization of cells that differentiate into xylem vessels. These PEP1-mediated developmental changes appear to be linked to the blockage of symplastic connections triggered by PEP1. PEP1 dramatically disrupts the symplastic movement of free green fluorescence protein (GFP) from phloem sieve elements to neighboring cells in the root meristem, leading to the deposition of a high level of callose between cells. Taken together, our first survey of PEP1-mediated vascular tissue development provides new insights into the PEP1 function as a regulator of cellular reprogramming in the Arabidopsis root vascular system.