• Journal of Plant Biotechnology
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• 제38권2호
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• pp.137-142
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• 2011

Auxin is a group of small natural and synthetic molecules having diverse regulatory functions in plant growth and development. In this review, two auxin binding proteins identified by biochemical experiments to measure their auxin binding activities and biochemical functions are described. ABP1, a 22 kDa auxin binding protein, shows strong auxin binding affinity and possibly plays an important role in plant development, although its biochemical function are still unclear. ABP57, a 57 kDa soluble protein from rice shoots, has both of IAA binding activity and the plasma membrane proton pump activation. Although it is yet to be accomplished, the improvement of agronomic traits using auxin binding proteins is worth to be considered, since auxin is known to be related to such a diverse crop traits.

• Plant Biotechnology Reports
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• 제3권4호
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• pp.293-299
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• 2009

Auxin-binding protein 57 ($ABP_{57}$), a soluble auxin-binding protein, acts as a receptor to activate plasma membrane (PM) $H^+-ATPase$. Here, we report the cloning of abp57 and the biochemical characterization of its protein expressed in E. coli. The analysis of internal amino acid sequences of $ABP_{57}$ purified from rice shoots enabled us to search for the corresponding gene in protein DB of NCBI. Further BLAST analysis showed that rice has four abp57-like genes and maize has at least one homolog. Interestingly, Arabidopsis seems to have no homolog. Recombinant $ABP_{57}$ expressed in E. coli caused the activation of PM $H^+-ATPase$ regardless of the existence of IAA. Scatchard analysis showed that the recombinant protein has relatively low affinity to IAA as compared to natural $ABP_{57}$. These results collectively support the notion that the cloned gene is responsible for $ABP_{57}$.

• BMB Reports
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• 제28권6호
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• pp.552-555
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• 1995

Treatment of microsomal vesicles isolated from etiolated Pisum sativum L cv. Alaska epicotyl tissue with agents inhibiting protein dephosphorylation, namely NaF and/or ATP, resulted in increased binding of the phytotropin NPA to the putative auxin efflux carriers localized on the plasma membrane. The phytotropin effect was especially conspicuous if the vesicles were simultaneously treated with Triton X-100. Kinetic analysis of the binding indicated the existance of two distinct sites for NPA, each having different affinities. Increased binding of the phytotropin to the membrane where protein dephosphorylation was inhibited was attributable to the increased ligand affinity of both sites. Treatment of tissue segments with flubride was found to enhance in vivo auxin transport. Implications of covalent modification of the auxin efflux carrier complex for the regulation of membrane transport of auxin molecules are discussed.

• Journal of Plant Biology
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• 제38권4호
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• pp.343-348
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• 1995

Treatment of Pisum sativum tissue with the protein kinase inhibitor staurosphorine resulted in impairment of 3H-indoleacetic acid transport in etiolated stem segments. The transport inhibitiion was accompanied by an increase in net uptake of labeled auxin in the tissue. The magnitude of auxin accumulation in tissue treated with the phytotropin N-1-naphthylphthalaic acid (NPA) which specifically blocks the efflux of auxin in the plasma membrane was reduced by the protein kinase inhibitor, suggesting that inhibition of protein phosphorylation could lead to hindrance of the auxin-exporting function of NPA receptors. The flavonoid genistein which is also known to inhibit protein kinase likewise reduced NPA-induced auxin accumulation. However, the flavonoid did not bring about auxin accumulation by itself, nor did it inhibit auxin transport. In view of the finding that the flavonoid also competes with NPA for a common binding site, a mechanism for the flavonoid effect on the NPA action will be proposed.

• Molecules and Cells
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• 제38권10호
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• pp.829-835
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• 2015

It has been suggested that AUXIN BINDING PROTEIN 1 (ABP1) functions as an apoplastic auxin receptor, and is known to be involved in the post-transcriptional process, and largely independent of the already well-known SKP-cullin-F-box-transport inhibitor response (TIR1) /auxin signaling F-box (AFB) ($SCF^{TIR1/AFB}$) pathway. In the past 10 years, several key components downstream of ABP1 have been reported. After perceiving the auxin signal, ABP1 interacts, directly or indirectly, with plasma membrane (PM)-localized transmembrane proteins, transmembrane kinase (TMK) or SPIKE1 (SPK1), or other unidentified proteins, which transfer the signal into the cell to the Rho of plants (ROP). ROPs interact with their effectors, such as the ROP interactive CRIB motif-containing protein (RIC), to regulate the endocytosis/exocytosis of the auxin efflux carrier PIN-FORMED (PIN) proteins to mediate polar auxin transport across the PM. Additionally, ABP1 is a negative regulator of the traditional $SCF^{TIR1/AFB}$ auxin signaling pathway. However, Gao et al. (2015) very recently reported that ABP1 is not a key component in auxin signaling, and the famous abp1-1 and abp1-5 mutant Arabidopsis lines are being called into question because of possible additional mutantion sites, making it necessary to reevaluate ABP1. In this review, we will provide a brief overview of the history of ABP1 research.

• EDISON SW 활용 경진대회 논문집
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• 제6회(2017년)
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• pp.16-26
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• 2017

Auxin response factor (ARF) and Aux/IAA transcriptional repressor family proteins play a major role in auxin's signalling process. Using the GALAXY protein modelling programs, monomer, dimer and oligomer structures of Aux/IAA17 and ARF5 protein were predicted based on the known experimental structures. By analysing the proposed complex structures, key interacting residues on binding site could be determined, and further suggestions for experimental studies were made.

• Genomics & Informatics
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• 제20권4호
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• pp.45.1-45.7
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• 2022

Food security will be affected by climate change worldwide, particularly in the developing world, where the most important food products originate from plants. Plants are often exposed to environmental stresses that may affect their growth, development, yield, and food quality. Auxin is a hormone that plays a critical role in improving plants' tolerance of environmental conditions. Auxin controls the expression of many stress-responsive genes in plants by interacting with specific cis-regulatory elements called auxin-responsive elements (AuxREs). In this work, we performed an in silico prediction of AuxREs in promoters of five auxin-responsive genes in Zea mays. We applied a data fusion approach based on the combined use of Dempster-Shafer evidence theory and fuzzy sets. Auxin has a direct impact on cell membrane proteins. The short-term auxin response may be represented by the regulation of transmembrane gene expression. The detection of an AuxRE in the promoter of prolyl oligopeptidase (POP) in Z. mays and the 3-fold overexpression of this gene under auxin treatment for 30 min indicated the role of POP in maize auxin response. POP is regulated by auxin to perform stress adaptation. In addition, the detection of two AuxRE TGTCTC motifs in the upstream sequence of the bx1 gene suggests that bx1 can be regulated by auxin. Auxin may also be involved in the regulation of dehydration-responsive element-binding and some members of the protein kinase superfamily.

• 생명과학회지
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• 제4권2호
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• pp.50-59
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• 1994

신호전달과정의 연구는 calcium이 messenger로서 작용한다고 밝혀진 후로 식물에서 $Ca^{++}$ -messenger system에 대한 생화학적 및 분자생물학적 분야에서의 연구는 급속하게 발전하게 되었다. 식물세포에서 calcium 이온들의 많은 작용은 EF hand family로서 알려진 calcium binding protein에 의해서 조절된다. Calmodulin (CaM)은 highy conserve 되어 있으며, 4개의 calcium binding domain을 가진 ubiquitous한 단백질이다. 본 연구는 calmodulin 유전자의 발현에 미치는 calcium, EGTA, calcium ionophore 및 calmodulin antagonist의 영향과 또한 외부신호(light, wounding), chemical 및 auxin 등의 영향을 reporter화 유전자의 분석에 의해서 CaM유전자의 발현기작을 규명하고자 하였고, 또한 calmodulin 유전자의 organ-specific 발현 및 calmodulin의 새로운 생리적인 기능도 연구하고자 하였다.

• 한국막학회:학술대회논문집
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• 한국막학회 1998년도 춘계 총회 및 학술발표회
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• pp.31-35
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• 1998

1. INTRODUCTION : Recognition and binding of organic substrates by biological molecules are of vital importance in biophysics and biophysical chemistry. Most studies of the application focused on the development of biosensors, which detected reaction products generated by the binding between enzymes and substrates. Other types of biosensors in which membrane proteins (e.g., nicotinic acetylcholine receptor, auxin receptor ATPase, maltose bining protein, and glutmate receptor) were utilized as a receptor function were also developed. In the previous study[1], the shifts in membrane potential, caused by the injection of substrates into a permeation cell, were measured using immobilized glucose oxidase membranes. It was suggested that the reaction product was not the origin of the potential shifts, but the changes in the charge density in the membrane due to the binding between the enzyme and the substrates generated the potential shifts. In this study, $\gamma$-globulin was immobilized (entrapped) in a poly($\gamma$-amino acid) network, and the shifts in the membrane potential caused by the injection of some amino acids were investigated.

• 생명과학회지
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• 제17권12호
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• pp.1649-1653
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• 2007

무더운 날씨가 지속됨으로서 고랭지배추의 생장 및 결구가 지연되고 있는 강원도 정선군 질운산(새빗재)의 600 m와 900 m의 배추를 사용하여 무기성분 및 단백질 발현패턴을 분석하였다. 식물체 무기성분에서는 생장에 관련된 질소 및 인산의 부족현상과 결구에 관련된 칼슘이 부족하였다. 단백체 분석은 2차원 전기영동에 의해 전체 126개의 단백질이 분리되었고 그중 48개의 단백질이 고도에 따라 변화하는 양상을 보여주었다. 이 중에서 30개의 단백질 서열이 결정되었는데, 해발 900 m에서 단백질 발현이 증가한 14개 중에서 oxygen- evolving proteins, rubisco activase and ATPase 등이, 해발 600 m에서는 glutathione S-transferase (1, 28 kD cold induced- and 24kD auxin-binding proteins) and salt-stress induced protein 등 16개의 단백질 발현이 증가하였다. 이러한 단백질은 식물체 손상에 대한 보호기작을 가진 스트레스관련 단백질로 가뭄, 온도상승, 밤낮의 온도차 등의 반복으로 복합적이며 동시 다발적으로 나타나는 고온장해 현상으로 사료된다.