• 제목/요약/키워드: endogenous auxin

검색결과 14건 처리시간 0.021초

안쪽으로 굽어지는 자엽초 박편의 옥신 반응을 촉진하는 옥수수(Zea mays) 내생물질의 탐색 (Screening of Endogenous Maize (Zea mays) Substances Enhancing Auxin-induced Inward Curvature in Coleoptilar Slits)

  • 박웅준
    • 생명과학회지
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    • 제16권5호
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    • pp.859-865
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    • 2006
  • 옥수수(Zea mays) 자엽초 박편을 분리하여 완충용액에 띄워 배양하면 조직 내부와 외부 사이의 장력 차이에 의하여 밖으로 굽어진다. 그러나 외부에서 옥신을 처리하면 안으로 굽어지는 반응이 나타나는데, 그 반응 정도는 옥신 농도에 따라 변화하였다. 본 연구에서는 옥신에 의하여 자엽초 박편이 안으로 굽어지는 현상을 옥신과 함께 작용하는 물질들을 선별하기 위한 실험에 이용하였다. 옥수수 자엽초의 메탄올 추출물로부터, 옥신에 의해 안으로 굽어지는 자엽초 박편의 반응을 촉진하는 활성을 발견하였다. 이러한 촉진 활성은 에너지원과 관련된 현상은 아니었다. 활성물질은 pH 10과 같은 높은 pH에서도 $C_{18}$ 컬럼에 흡착되어 메탄올로 용리되었으며, 50% 메탄올과 80% 메탄올에 의하여 용리되는 두 가지 물질을 발견하고 각각 Curvature-Enhancing Factor-1 (CEF-1)과 Curvature-Enhancing Factor-2 (CEF-2)라 명명하였다. 그중 CEF-2의 HPLC를 이용한 분리 조건이 확립되었다.

Sensitivity Changes of Auxin Transport System in Maize Coleoptile Segments

  • 윤인선
    • Journal of Plant Biology
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    • 제36권1호
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    • pp.59-66
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    • 1993
  • In maize coleoptile segments where auxin transport capacity decreases with time following excision, susceptability of the tissue to transport inhibitors such as N-1-naphthylphthalamic acid (NPA), 3,4,5-triiodobenzoic acid (TIBA) or high concentrations of IAA was found to be rather increased. A time-dependent increase in the sensitivity to NPA can be postulated since the dose-response curve for NPA was shifted in the‘aged’tissue to the left (i.e. lower concentration). Preincubation of the tissue at a low temperature abolished the time-dependent sensitivity change, suggesting that cellular metabolism could be involved. The NPA-sensitive state was also brought about by calcium depletion of the tissue, which can be partially reversed by addition of calcium. Presence of exogenous IAA in the preincubation medium kept the auxin transport system from decay, implicating auxin as an endogenous controlling factor. Results of our experiments indicate a reversible, time-dependent changes of auxin transport system in which transport capacity and sensitivity to NPA are tightly coupled. Changes in the sensitivity to NPA were also seen in auxin action as well.

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관상식물 삽목발근에 있어서 NAA, IBA 및 Ethychlozate의 발근촉진효과와 그 생리학적연구 (The Promotive Effect of NAA, IBA and Ethychlozate on Rooting Cuttings of Certain Ornamental Plants and Some Physiological Studies.)

  • 정해준;곽병화
    • 자연과학논문집
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    • 제1권
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    • pp.115-198
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    • 1987
  • The present studies were undertaken to elucidate the influence of auxins, auxin-like substance-ethychlozate ("Figaron"),and pH and sort of rooting media on rooted propagation of certainornamental woody plant cuttings, and to see possible changes in internal compositions characterizing after root-promoting treatment as the cutting stage proceeded. The experimental check-up srevealed and summarized as seen in the following;I. Effect of three different auxin treatments on rooting cuttings: 1) Promotive influence of auxin varied according to different concentration levels, hours of dipping treatment of the auxins, and kind of plants. The greatest effect was obtained for Forsythia ksreana with NAA and IBA, for Ligustrurn obtusifolium var. variegatum with NAA and ethychlozate, for Hydrangea macrophylla, Magnolia kobus, and Magnolia liliflora with NAA, lBA and ethychlozate also. The most effective level of the promotive agents was found 200mg/l for NAA, 1000mg/l for IBA, and 200mg/l for ethychlozate. For Weigela florida and Gardenia jasminoides, range of the most effective level was shown relatively wide spread. 2) NAA was more effective at its optimal level of the rooting agent than ethychiozate for Weigela florida, Viburnum awabuki, Forsythia koreana, Acer palmatum 'Nomura', Bouga invillea glabra, Elaeagnus umbellata, Prunus tomentosa, Ligustrum obtusifolium, Pyracantha coccinea, Cestrum noctu rnum, Hydrangea macrophylla, Codiaeum variegatum, Rhododen dron lateritium, and Ilex crenata var. macrophylla, and yet ethychlozate was found either as equally as effective or more so than NAA for Zebrina pendula, Hibiscus syriacus, Fatshedera lizei, Schefflera arboricola, Campsis grandiflo ra, Ixora chinensis, Euonymus japonica, and Magnolia liliflora. On the contrary, no the auxin effect was noted with Lagerstroemia indica, Trachelospermum asiaticum, and Syringa vulgaris. This probably indicates that these species are genetically different for the auxin response.II. Effect of different pH and sorts of cutting media on rooting cuttings: 1) Bougainvillea showed best in rooting for the number and dry weight at pH 6.5, more with ethychlozate than NAA, while Ligustrum did at pH 5.0 more with NAA than ethychlozate. pH 4.0 medium resulted in the best rooting for Rhododendron with NAA, more than ethychlozate. 2) Use of cutting medium with peat: perlite: vermiculite = 1:1:1 showed to give the greatest rooting percent and dry weight, apart from considering the number of roots. This apparently meant the fact that cutting medium has more to do with root growth than root differentiation. Rhododendron yet showed results with cutting media that use of peat: perlite = 2:1 mixed is more effective on rooting than using peat alone.III. Effect of auxinic treatments on rooting cuttings and change in some cutting compositions: 1) Under the climatic conditions of July having temperature $26.3\pm$$2.4^{\circ}C$for cutting bed, new roots of Magnolia started to show up generally 20 days after the cutting was made, whereas Cestrum did much earlier than that, namely 14 days after. 2) Although total carbohydrate content of Magnolia cuttings showed no marked change without auxin treatment, it did so with the treatment, especially 30 days after the start of cutting. Cestrum cuttings demonstrated a gradual in crease in total carbohydrate content as rooting took place, and the content became reduced more with auxin than with out, just about when rooting proceeded to 14 days after the start of cutting. 3) Magnolia generally showed an increase in total nitrogen content as rooting proceeded more, and Cestrum showed a decrease in total nitrogen of cuttings. The auxin treatment exhibited no pertinent relation with change in plant nitro gen when rooting is promoted with auxin treatment. 4) An abrupt drop of total sugar and reducing sugar was noticed as Magnolia rooting started, and this reduction was parti cularly outstanding with auxin treatment. Starch content also was decreased in the later stage of cutting with auxin treatment, and was rather increased without auxin. Although sugar content soon increased as cutting started with auxin treatment in the case of Cestrum, it became reduced after rooting took place. 5) Total phenol content increased with rooting, and this was especially true when rooting started. This increase was reversed somehow regardless of auxin treatment. A decrease in phenol of Magnolia was found more striking with auxin than without in the later stage of the cutting period. 6)Avena coleoptile test for auxin-like substances presented the physiologically active factor is more in easy-to-root Magnolia liliflora than hard-to-root Magnolia kobus, and the activity of auxin-like substances was much increased with auxin treatment. The increase in the growth promoting substances was markedly pronounced when rooting just started. The active growth substances decreased in the later stage of cutting, and certain inhibitory substances started appearing. Cestrum also showed physiologically similar growth promoting substances accompanying auxin-like active substances if auxin is treated, and some strong inhibitory substances seemed to appear in the later stage of cutting. 7) Mung-bean-rooting test indicated biologically that endogenous growth substances in Magnolia all promoted mung-bean rooting, and activity of the growth substances apparently stimulated mung-bean rooting with auxin more than without. Here auxin treatment seemed to give a rise to an increased activity of endogenous growth substances in cuttings. This activity was found much greater with either NAA or IBA than ethychlozate, and showed its peak of the activity when rooting first started taking place. Certain inhibitory substances for Avena coleoptile growth strongly promoted mung-bean rooting, and it was also much like in the case of Cestrum.

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Ranunculus sceleratus 엽병의 에틸렌 매개 생장반응조절에 있어서 Spermine의 관여 (Involvement of spermine in Control of Ethylene-Mediated Growth Response in Ranunculus sceleratus Petioles)

  • 정미숙
    • Journal of Plant Biology
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    • 제35권4호
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    • pp.425-429
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    • 1992
  • Ranunculus sceleratus 엽병의 세포 신장은 에틸렌에 의하여 촉진되는 것으로 알려져 있다. 오옥신을 처리한 엽병조직 절편에서 spermine은 세포 신장과 에틸렌의 생성을 비슷한 양상으로 억제하였다. Spermine 농도에 대한 오옥신 유도 에틸렌 생성 억제반응은 ACC에 의한 에틸렌 생성의 경우도 유사한 양상을 나타내었으며 이는 폴리아민이 ACC가 에틸렌으로 전환되는 과정을 억제한다는 것을 시사한다. 오옥신 유도 에틸렌 생성은 폴리아민 생합성 억제제인 DFMA아 DFMO에 의하여 각각 현저하게 촉진되었으며 DFMA에 의한 에틸렌 생성의 증가는 spermine을 고농도로 처리하므로써 완전히 소멸되는 결과를 얻었다. 이러한 결과들은 오옥신과 에틸렌에 대한 Ranunculus의 세포성장 반응에서 내생 폴리아민이 조절 역할을 수행한다는 가능성을 입증하는 것이다.

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완두 돌연변이체 ageotropum 뿌리의 중력불감성 (Insensitivity of the ageotropum Pea Mutant Roots to Gravity)

  • Kim, Jeong-Im;Bin G. Kang
    • 식물조직배양학회지
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    • 제22권6호
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    • pp.345-350
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    • 1995
  • 완두 돌연변이체 ageotropum 뿌리의 굴중성 결여에 대하여 조사하였다. 정상 완두의 뿌리에서 에틸렌은 굴중성 반응을 억제하였다. 돌연변이체에서는 에틸렌이나 에틸렌 생합성 억제제 또는 작용 억제제 모두 뿌리의 굴중성 반응 결여를 회복시키지 못하였다. 옥신을 비대칭으로 처리한 뿌리에서 굴성반응이 일어나는 것으로 보아 옥신의 작용은 정상적으로 일어나는 것으로 판단되었다. 내생적 또는 옥신유도에 의한 에틸렌 생성은 정상 완두나 돌연변이체에서 크게 차이가 없었다. 그러나 정상 완두에서와는 달리 돌연변이체의 뿌리에서는 굴중성 반응의 작동체계인 옥신작용의 결함이 아니고 중력의 인식 또는 전달과정에 결함이 있다는 결론을 얻었다.

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Immunohistochemical Localization of Endogenous IAA in Peach (Prunus persica L.) Fruit during Development

  • Zhang, Wei;Li, Yang;Shi, Mengya;Hu, Hao;Hua, Baoguang;Yang, Aizhen;Liu, Yueping
    • 원예과학기술지
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    • 제33권3호
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    • pp.317-325
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    • 2015
  • Peach (Prunus persica L.) is a model species for stone fruit studies within the Rosaceae family. Auxin plays an important role in the development of peach fruit. To reveal the distribution of auxin in the tissues of peach fruit, immunohistochemical localization of IAA was carried out in the seed, mesocarp, and endocarp in developing peach fruit using an anti-indole-3-acetic acid (anti-IAA) monoclonal antibody. A strong IAA signal was observed throughout the outer and inner integument during peach fruit development, and the distribution was zonal. The IAA signal was mainly focused in mucilage layers in the outer integument. The outer integument may function to produce or store IAA in the seed; a strong IAA signal was detected in the cells around the vascular tissue, whereas a weak IAA signal was located in the vascular tissues. In the mesocarp, the cells around the vascular bundle tissue gave rise to an IAA signal that increased in the late phase of fruit growth, which coincided with a significant increase in fruit growth. The distribution of IAA, however, was changed when fruit was treated with auxin transport inhibitors NPA (1-N-naphthylphthalamic acid) or TIBA (2, 3, 5-triiodobenzoic acid); in mesocarp tissues, an IAA signal was detected mainly in vessels of the treated fruit. During the critical period of endocarp lignification, the vessel lignification process was negatively correlated with IAA signal. The present results confirmed that the distribution of IAA was different in various tissues of peach fruit according to the developmental stage. This research provides cytological data for further study of the regulatory mechanism of auxin in peach fruit.

강낭콩 하배축 절편의 부정근형성에 미치는 내재 IAA의 이동 (Effect of Endogenous IAA Transport on Adventitious Root Formation in Phaseolus vulgaris Hypocotyl Cuttings)

  • 조덕이
    • Journal of Plant Biology
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    • 제32권4호
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    • pp.323-330
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    • 1989
  • This work was carried out to elucidate effects of endogenous and exogenous IAA transport on adventitious root formation in Phaseolus vulgaris hypocotyl cuttings. For inverted or normal incubation in distilled water, the adventitious root is always formed at the morphological base but not at the morphological apex. For inverted incubation, in both distilled water and certain chemical solution, the root formation is retarded more at the first stage (0-24 hr) than at the second stage (24-48 hr). When p-chlorophenoxyisobutyric acid (PCIB) was applied to the cuttings at the first stage, theroot formation was inhibited more than at the second stage. Treatment of 2,3,5-triiodobenzoic aicd (TIBA)markedly inhibited the adventitious root formation in Phaseolus vulgaris hypocotyl cuttings. This inhibition influenced the root according to the applied stage and period. Therefore, the root formation is more related to the stage of root primordium formation than to the stage of root elongation from the primordium. Inhibition of auxin transport oraction by TIBA or PCIB could also be reversed when hypocotyl cuttings are incubated in exogenously applied IAA solution.

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PIF4 Integrates Multiple Environmental and Hormonal Signals for Plant Growth Regulation in Arabidopsis

  • Choi, Hyunmo;Oh, Eunkyoo
    • Molecules and Cells
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    • 제39권8호
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    • pp.587-593
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    • 2016
  • As sessile organisms, plants must be able to adapt to the environment. Plants respond to the environment by adjusting their growth and development, which is mediated by sophisticated signaling networks that integrate multiple environmental and endogenous signals. Recently, increasing evidence has shown that a bHLH transcription factor PIF4 plays a major role in the multiple signal integration for plant growth regulation. PIF4 is a positive regulator in cell elongation and its activity is regulated by various environmental signals, including light and temperature, and hormonal signals, including auxin, gibberellic acid and brassinosteroid, both transcriptionally and post-translationally. Moreover, recent studies have shown that the circadian clock and metabolic status regulate endogenous PIF4 level. The PIF4 transcription factor cooperatively regulates the target genes involved in cell elongation with hormone-regulated transcription factors. Therefore, PIF4 is a key integrator of multiple signaling pathways, which optimizes growth in the environment. This review will discuss our current understanding of the PIF4-mediated signaling networks that control plant growth.

Cymbidium sp. Protocorm의 묘조분화시 내생 Polyamine 함량의 변화 (Change of Endogenous Polyamines During Shoot Differentiation in Cymbidium sp. Protocorms)

  • 한태진
    • Journal of Plant Biology
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    • 제33권1호
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    • pp.41-48
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    • 1990
  • Changes in polamine titers during shoot differentiation in Cymbidium sp. (Jungfrau) protocorms were studied in order to investigate the mechanism of shoot differentiation by using auxin-inhibitors(PCIB, TIBA), hormones(GA3, ABA, BA), and phenolic compounds (2,4-dichlorophenol, catechol). The shoot differentiation and propagation of protocorms were promoted by PCIB or 2,4-dichlorophenol, and the growth of differentiated shoot were promoted by TIBA or catechol. In BA-treated protocorms, white or brown protocorms were observed. Putrescine was the most abundant polyamine during the propagation and differentiation processes. As compared with putrescine, spermidine did not show significant changes and spermine was not detected at all. Putrescine titers decreased after a temporary increase, and then again increased in the presence of GA3, ABA, 2,4-dichlorophenol, and then again increased in the presence of GA3, ABA, 2,4-dichlorophenol, catechol, or PCIB. But, in BA-treated protocorms, putrescine level was much lower than spermidine.

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Brassinolide와 Auxin과의 상호작용의 생물검정에 의한 평가 (Interaction between Brassinolide and Auxins on Bioassays)

  • 최충돈;김순철;이수관
    • 한국작물학회지
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    • 제35권1호
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    • pp.58-64
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    • 1990
  • 최근 국내에서 연구가 시작되고 있는 신규 식물생장조정제인 brassinolide류와 기존의 auxin류를 혼용하였을 경우 상호작용성을 구명하여 농업적 이용의 기초자료를 얻고자 몇가지 생물검정법을 이용하여 상호작용의 결과를 분석해 본 결과를 요약하면 다음과 간다. 1. 벼 엽신기부굴절검정에서는 두 화합물의 저농도 혼용조합에서 길항적인 반응을 보였으나, 대부분의 조합에서는 상가 또는 상승작용을 하였으며, 고농도의 혼용일수록 상승효과가 높았고, IAA가 2, 4-D에 비해 다소 혼용효과가 높았다. 2. 귀리 자엽소신장검정에서는 HBR의 농도에 관계없이 IAA 0.1ppm 이하에서는 상승작용을 하였으나 0.3ppm 이상의 혼용에서는 상가적인 반응을 나타내었다. 3. 무 하배축신장검정에서는 자엽의 유무에 의해 반응이 다르게 나타났는데, 자엽을 제거한 절편에서는 IAA 3ppm과 HBR과의 혼용조합을 제외하고는 대부분의 혼용조합이 길항적인 반응을 보였다. 4. 이상에서와 같이 검정방법간 혼용효과가 뚜렷한 차이가 있었으며, 공시재료에 따라 상호작용의 효과가 다르게 나타났는데 auxin의 함량이 비교적 높은 생장점을 가진 절편에서는 대체로 길항작용을 보인 반면, 선단부를 제거하여 내생호르몬이 불안정한 절편에서는 상가 또는 상승작용을 보였다.

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