• 한국전자현미경학회:학술대회논문집
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• 한국현미경학회 2001년도 제32차 추계학술대회
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• pp.35-36
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• 2001

• Journal of Applied Biological Chemistry
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• 제51권3호
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• pp.102-110
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• 2008

Complementation assay of the urea uptake-defective yeast mutants led to the identification of the Arabidopsis AtTIP4;1 gene encoding the aquaporin. However, its physiological functions still remain elusive. In the present study, histochemical and genetic analyses were performed to understand the physiological roles of AtTIP4;1 in urea uptake. The AtTIP4;1 product was detectible in the roots, but not in the leaves, the stem, and the flower. Its promoter allowed the expression of the $\beta$-glucuronidase reporter gene in the roots and the apical meristem in Arabidopsis. The AtTIP4;1 products were induced under nitrogen-deficient conditions. To investigate the role of the tonoplast intrinsic protein in urea transport and developments, Arabidopsis with the loss- and the gain-of-function mutations by T-DNA insertion in AtTIP4;1 and 35S promoter-mediated overexpression of AtTIP4;1 were identified, respectively. The transfer DNA insertion and the AtTIP4;1-overexpressed plants showed normal growth and development under normal or abiotic stress growth conditions. The urea-uptake studies using $^{14}C$-labeled urea revealed higher accumulation of urea in the AtTIP4;1-overexpressed plants. These results provide evidence that overexpression of AtTIP4;1 leads to the increase in the urea-uptake rate in plants without detectable defects to the growth and development.

• The Plant Pathology Journal
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• 제37권2호
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• pp.182-193
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• 2021

The transcription factor SHE1 was identified as an interacting partner with the cucumber mosaic virus (CMV) 1a protein in the yeast two-hybrid system, by a pull-down assay, and via bimolecular fluorescent complementation. Using fluorescent-tagged proteins and confocal microscopy, the CMV 1a protein itself was found distributed predominantly between the nucleus and the tonoplast membrane, although it was also found in speckles in the cytoplasm. The SHE1 protein was localized in the nucleus, but in the presence of the CMV 1a protein was partitioned between the nucleus and the tonoplast membrane. SHE1 expression was induced by infection of tobacco with four tested viruses: CMV, tobacco mosaic virus, potato virus X and potato virus Y. Transgenic tobacco expressing the CMV 1a protein showed constitutive expression of SHE1, indicating that the CMV 1a protein may be responsible for its induction. However, previously, such plants also were shown to have less resistance to local and systemic movement of tobacco mosaic virus (TMV) expressing the green fluorescent protein, suggesting that the CMV 1a protein may act to prevent the function of the SHE1 protein. SHE1 is a member of the AP2/ERF class of transcription factors and is conserved in sequence in several Nicotiana species, although two clades of SHE1 could be discerned, including both different Nicotiana species and cultivars of tobacco, varying by the presence of particular insertions or deletions.

• Journal of Plant Biotechnology
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• 제37권4호
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• pp.517-528
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• 2010

종자 발달과 발아는 수분과 양분 함량의 급격한 변화를 수반하는 복합적인 과정이다. 본 연구에서는 유전자 발현과 단백질 구조 비교 분석을 통해 벼 종자의 발아와 발달과정에 관여하는 액포막 aquaporin (tonoplast intrinsic protein)을 규명하였다. OsTIP3;1, OsTIP3;2는 종자 특이적인 TIP로 종자가 성숙되는 시기에 발현되었다가, 종자가 발아하면서 전사체가 사라지는 양상을 보였으며, ABA 처리에 의해 발현이 유도되었다. 단백질 구조 예측 결과로부터 OsTIP3;1, OsTIP3;2가 단백질의 N-말단, B와 E loop에 다른 TIP와 뚜렷이 구분되는 인산화 잔기 특징을 확인하였다. OsTIP2;1과 OsTIP4;3은 종자가 발달하는 과정에서 유전자 발현이 감소하였다가, 종자 발아 후기에 뿌리와 배축의 신장이 활발한 시기에 발현이 급증하였다. 특히 OsTIP2;1은 뿌리에서 강한 발현을 보였으므로, 뿌리 생장에 필요한 팽압 공급에 중요한 기능을 할 것으로 제안된다. OsTIP2;1과 OsTIP4;3 단백질의 N-말단에는 특징적으로 메틸화 (methylation) 가능성이 높은 아미노산 잔기가 예측되었다. OsTIP2;2는 OsTIP2;1과는 달리 종자 침윤 후 7시간 이내에 발현이 빠르게 유도되며, 발아가 억제되는 조건에서도 유전자 발현이 유지되는 것으로 보아 종자의 초기 수화 과정에 관여할 것으로 추측된다. OsTIP2;2 단백질의 N-말단에는 OsTIP2;1에 존재하는 인산화 Ser 잔기와 메틸화 잔기가 결실된 특징을 보였다. 이런 결과들은 벼 종자의 발달과 발아 과정에서 나타나는 액포의 종류와 기능에 따라 서로 다른 TIP가 선택적으로 유전자 발현수준에서 조절되며, 인산화, 메틸화 등 단백질 수식에 의한 활성조절 기작 역시 매우 다르다는 것을 시사한다.

• The Plant Pathology Journal
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• 제18권6호
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• pp.301-307
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• 2002

Graft transmission and cytopathological studies of a severe pear disease, pear black necrotic leafspot（PBNLS), were carried out to determine the causal agent of the disease. No evidence was found that a fungal or bacterial pathogen could be the causal agent of the disease. Attempts to transmit the agent by sap-inoculation to other plants including herbaceous hosts failed. How-ever, the pathogen was readily graft-transmitted from symptomatic diseased pears to healthy pears. Graft transmission of the pathogen was also demonstrated by using an indicator plant, PS-95, developed in the laboratory through various grafting methods. Ultrastructural study of the disease revealed the consistent presence of flexuous rod-shaped virus-like particles (VLP) in the symptomatic leaves of both Niitaka cultivar and indicator pear, PS-95. The particles, approximately 12 nm in diameter with undetermined length, occurred in the cytoplasm of mesophyll parenchyma cells. Cells with VLPs also contained fibril-containing vesicles, which are common in cells infected with plant viruses with ssRNA genome. The vesicles were formed at the tonoplast. Based on the symptomatology, the presence of fibril-containing vesicles, and graft-transmissibility, it is believed that the VLPs that occurred on symptomatic leaves of black necrotic leafspot of pear are viral in nature, possibly those of a capillovirus.

• Journal of Plant Biology
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• 제33권4호
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• pp.325-332
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• 1990

Light membrane vesicles were isolated from the zucchini hypocotyl by floatation on ficoll density gradients and the proteins were solubilized with Triton X100. Three ATP-hydrolyzing enzymes were partially purified by ion-exchange and gel filtration chromatography and isoelectric focusing. There are plasma membrane-type ATPase whose activity was inhibited by vanadate but not by nitrate, tonoplast-type ATPase which was sensitive to nitrate but insensitive to vanadate and one having a phosphatase activity with a pI value different from that of an acid phosphatase. A fraction was obtained after DEAE-ion-exchange chromatography crossreacting with polyclonal antibodies against Ca2+ -ATPase from human erythrocytes.

• BMB Reports
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• 제45권2호
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• pp.96-101
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• 2012

Urea-based nitrogen fertilizer was widely utilized in maize production, but transporters involved in urea uptake, translocation and cellular homeostasis have not been identified. Here, we isolated three maize aquapoin genes, ZmNIP2;1, ZmNIP2;4 and ZmTIP4;4, from a cDNA library by heterogous complementation of a urea uptake-defective yeast. ZmNIP2;1 and ZmNIP2;4 belonged to the nodulin 26-like intrinsic proteins (NIPs) localized at plasma membrane, and ZmTIP4;4 belonged to the tonoplast intrinsic protein (TIPs) at vacuolar membrane. Quantitative RT-PCR revealed that ZmNIP2;1 was expressed constitutively in various organs while ZmNIP2;4 and ZmTIP4;4 transcripts were abundant in reproductive organs and roots. Expression of ZmTIP4;4 was significantly increased in roots and expanded leaves under nitrogen starvation, while those of ZmNIP2;1 and ZmNIP2;4 remained unaffected. Functions of maize aquapoin genes in urea transport together with their distinct expression manners suggested that they might play diverse roles on urea uptake and translocation, or equilibrating urea concentration across tonoplast.

• Journal of Plant Biology
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• 제38권4호
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• pp.381-388
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• 1995

해녀콩(Canavalia lineata) 뿌리혹으로부터 만들어진 cDNA library를 뿌리의 총 RNA, leghemoglobin 및 uricasell cDNA를 competitor로 사용하여 차등 혼성화반응으로 후기 뿌리혹에서 발현되며 Cno이, Cne2, Cne3, Clb2로 명명된 4개의 cDNA 클론을 얻었다. Cnod1은 벼의 cysteine proteinase를 암호화하는 유전자와 유사한데 1450nt의 전사체외 혼성화 반응을 보였으며 뿌리혹에서만 발현되고 뿌리혹 발달 후기에서 가장 높은 발현을 보였다. Cne2는 벼의 Expressed Sequence Tag의 한 종류와 유사하고 900 nt의 전사체와 혼성화 반응을 보였으며 뿌리혹에서 주로 발현되었다. Cne2는 접종 후 13일째 발현이 증폭된 후 일정하게 유지되었다. Cne2는 완두의 tonoplast 막 내재 단백질 TRG31을 암호화하는 유전자와 유사하며 뿌리에서 가장 많이 발현되었다. Cne3는 1700 nt와 1400 nt의 전사체와 혼성화반응을 보였으며 뿌리혹의 성장, 발달과 일치하는 발현 양상을 보였다. Clb2는 800 nt의 전사체와 혼성화반응을 보였으며 접종 후 8일째부터 발현이 시작되어 13일째 증폭되고 그 이후 일정한 수준을 유지하였다.

• 아시안잔디학회지
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• 제11권1호
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• pp.9-22
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• 1997

This study was performed to elucidate the mechanisms involved in efflux process of phosphate from intact and excised roots of Oryza sativa (Tongil). The rapid loss of phosphate during the first 40-minutes of treatment is mainly from the cytoplasmic fraction, and the gradual loss taking place afterwards is possibly reflecting the losses at the tonoplast. During the first 60 minutes, loss of phosphate from the excised roots treated with KCN was more rapid than the control but slower thereafter. The effect of $CaCl_2$ and KCl appeared to decrease the rate of phosphate efflux in excised roots of rice. The mechanism of phosphate efflux by rice roots seems to be passive and oscillatory in the short period. Key words: Oryza sativa(Tongil), Phosphate efflux.

• 한국식물병리학회지
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• 제12권3호
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• pp.368-373
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• 1996

배나무잎 검은점병에 이병된 신고와 지표식물 PS-95의 잎을 전자현미경으로 세포내 미세구조를 검경한 결과 굴곡성 사상형 유사바이러스 입자가 집단으로 존재하고 있는 것을 확인하였다. 엽육유세포질에 있는 유사바이러스 입자들의 직경은 12 nm였으나 입자들의 길이는 측정하지 못하였다. 섬유사를 함유하고 있는 소포는 일반적으로 ssRNA genome을 갖는 식물바이러스에 의해 이병된 세포에서 생성된다. 본 연구에서 이 소포들은 tonoplast에 형성되었다. 배나무잎 검정점병의 이병잎을 초본 지표식물에 즙액접종하였으나 어떠한 병징도 나타나지 않았다. 또한 접목접종 전염에 의하여 전염되어 전형적인 검은점이 발병하였다. 발병된 잎에는 유사바이러스 입자가 존재하고 있었다. 이상의 결과 병징, 섬유사를 함유한 소포의 존재, 그리고 접목전염을 기초로하여 볼 때 배나무 검은점병을 일으키는 유사바이러스 입자는 closteroviruses의 하나로 생각된다.