• 한국미생물·생명공학회지
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• 제33권3호
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• pp.189-193
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• 2005

RBL-2H3 cell lysates에 anti-protein phosphatase(PP) 1, 2A, 2B 항체를 첨가한 후 immunoprecipitation을 실시한 결과 PP2B를 가해준 샘플에서만 HRF를 확인하였다. 역으로 monoclonal anti-HRF 항체를 가한 후 immunoprecipitation을 실시한 결과 PP1, 2A는 검출되지 않았으나 PP2B의 경우는 regulatory subunit(19 kDa), catalyic subunit(60 kDa) 모두 확인할 수 있었다. Affinity chromatography를 통해서도 PP2B가 HRF의 탈인산화에 관여함을 확인하였다 즉 19kDa의 PP2B regulatory subunit과 60kDa의 catalytic subunit 모두가 확인되었으며 외부 $Ca^{2+}$이온 첨가 여부에 따른 차이는 관찰할 수 없었다. 결론적으로 RBL-2H3 cell에서 PP2B는 PP1이나 PP2A에 비해 상대적으로 그 존재량은 적으나 HRF와 상호작용하는 phosphatase로서 검출된 반면 PP1이나 PP2A는 검출되지 않았다.

• 폴리머
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• 제39권1호
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• pp.180-184
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• 2015

폴리프로필렌(PP)으로 그래프트된 그래핀 옥사이드(PP-grafted GO)는 2-bromoisobutyryl 그룹을 가진 GO(GO-Br)와 하이드록시 그룹을 가진 PP(PP-OH)와의 "grafting-to" 화학반응을 통하여 제조하였다. GO-Br은 GO와 2-bromoisobutyryl bromide를 염기촉매 하에서 반응시켜 얻을 수 있었고, PP-OH는 maleic anhydride가 그래프트된 PP(PP-MAH)와 ethanolamine과 반응하여 제조하였다. 제조된 PP-grafted GO는 PP-OH에 비하여 녹는점이 높은 온도로 이동하였고, 열적 안정성은 GO와 PP-OH에 비하여 우수한 것을 확인하였다. 이러한 결과는 그래프트된 PP 고분자가 GO의 열적 안정성을 향상시키는 것으로 판단된다. 또한 PP-grafted GO의 표면은 GO-Br에 비하여 거칠기가 증가되는 것을 확인하여 PP가 GO 표면에 화학적으로 결합한 것을 알 수 있었다. 제조된 PP-grafted GO의 분석은 FTIR, Raman, DSC, TGA, SEM과 같은 다양한 분석장비를 이용하여 수행하였다.

• Molecules and Cells
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• 제42권7호
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• pp.546-556
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• 2019

Protein phosphatase 4 (PP4) is a crucial protein complex that plays an important role in DNA damage response (DDR), including DNA repair, cell cycle arrest and apoptosis. Despite the significance of PP4, the mechanism by which PP4 is regulated remains to be elucidated. Here, we identified a novel PP4 inhibitor, protein phosphatase 4 inhibitory protein (PP4IP) and elucidated its cellular functions. PP4IP-knockout cells were generated using the CRISPR/Cas9 system, and the phosphorylation status of PP4 substrates (H2AX, KAP1, and RPA2) was analyzed. Then we investigated that how PP4IP affects the cellular functions of PP4 by immunoprecipitation, immunofluorescence, and DNA double-strand break (DSB) repair assays. PP4IP interacts with PP4 complex, which is affected by DNA damage and cell cycle progression and decreases the dephosphorylational activity of PP4. Both overexpression and depletion of PP4IP impairs DSB repairs and sensitizes cells to genotoxic stress, suggesting timely inhibition of PP4 to be indispensable for cells in responding to DNA damage. Our results identify a novel inhibitor of PP4 that inhibits PP4-mediated cellular functions and establish the physiological importance of this regulation. In addition, PP4IP might be developed as potential therapeutic reagents for targeting tumors particularly with high level of PP4C expression.

• The Plant Pathology Journal
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• 제28권3호
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• pp.259-269
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• 2012

Protein phosphatase 2A (PP2A), a family of serine/threonine protein phosphatases, plays an important role in balancing the phosphorylation status of cellular proteins for regulating diverse biological functions in eukaryotic organisms. Despite intensive studies in mammals, limited information on its role is available in filamentous fungi. Here, we investigated the functional roles of genes for a putative B' delta regulatory subunit (FgPP2AR) and a catalytic subunit (FgPP2AC) of PP2A in a filamentous ascomycete, Fusarium graminearum. Molecular characterization of an insertional mutant of this plant pathogenic fungus allowed us to identify the roles of FgPP2AR. Targeted gene replacement and complementation analyses demonstrated that the deletion of FgPP2AR, which was constitutively expressed in all growth stages, caused drastic changes in hyphal growth, conidia morphology/germination, gene expression for mycotoxin production, sexual development and pathogenicity. In particular, overproduction of aberrant cylindrical-shaped conidia is suggestive of arthroconidial induction in the ${\Delta}FgPP2AR$ strain, which has never been described in F. graminearum. In contrast, the ${\Delta}FgPP2AC$ strain was not significantly different from its wild-type progenitor in conidiation, trichothecene gene expression, and pathogenicity; however, it showed reduced hyphal growth and no perithecial formation. The double-deletion ${\Delta}FgPP2AR;{\Delta}FgPP2AC$ strain had more severe defects than single-deletion strains in all examined phenotypes. Taken together, our results indicate that both the putative regulatory and catalytic subunits of PP2A are involved in various cellular processes for fungal development in F. graminearum.

• Journal of Animal Science and Technology
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• 제62권5호
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• pp.702-712
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• 2020

Synthetic nitrite imparts a reddish-pink color to meat and a distinct flavor to meat products, delays lipid oxidation, and inhibits microbial growth and pathogens. However, excessive intake of nitrite might result in the production of carcinogenic nitrosamine, which might increase the risk of cancer in humans. Therefore, we aimed to find an alternative natural colorant for pork sausages. Pork sausages were mixed with 0.014% sodium nitrite (NaNO₂) alone (CON), without either NaNO₂ or purple-fleshed sweet potato powder (PP; CON1), 0.5% PP alone (PP1), 1% PP (PP2) alone, 0.011% NaNO₂ and 0.5% PP (SP1), and 0.011% NaNO₂ and 1% PP (SP2). The sausages were then cooked and stored for physicochemical analysis on days 0, 5, 10, 15, and 20. The a* and W* values were the greatest and lowest in the SP2 and CON1 treatments, respectively (p < 0.05). The concentrations of residual nitrite in the sausages at 20 days decreased in the order of CON > SP1, SP2 > PP2 > PP1, CON1. The fatty acid content was higher, and flavorous amino acids were more in PP2 (p < 0.05). The fatty acid composition was comparable between the SP2 and CON groups, but the contents of glutamic acid and alanine were greater in the SP2 group. In conclusion, SP2 (0.011% NaNO₂ with 1% PP) could be added as a natural colorant for pork sausage production, and NaNO₂ could be substituted with up to 20% PP without detrimental effects on sausage appearance and/or quality.

• 한국응용과학기술학회지
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• 제15권1호
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• pp.1-7
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• 1998

Lubricating softner(SOS-2) for permanent press(PP) finish was prepared by blending water, beef tallow hardened oil for improving softness, and the emulsion which was synthesized from N-hexadecanoyl-N,N'-bis(2-hexadecamidoethyl)amine as a softening component and silicone oil KF-96 as a lubricating component. The prepared SOS-2 and the PP finishing resin were applied to PP finishing cotton broad cloth and P/C gingham samples using one bath method. The properties such as tear strength, crease recovery, bending resistance test were tested. The samples treated with SOS-2 and PP finishing resin have improved properties, compared with nontreated samples, those treated only with PP finishing resin, those treated with commercial PP finishing softners and PP finishing resin.

• Elastomers and Composites
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• 제49권3호
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• pp.225-231
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• 2014

본 연구에서는 폴리프로필렌 (PP)과 에틸렌 비닐알코올 공중합체 (EVOH)의 블렌드에 있어 발생하는 상분리 현상을 방지하고자 PP에 itaconic acid (IA)가 그라프트 된 PP-g-IA 를 상용화제로 이용하였다. PP-g-IA 상용화제는 PP base에 IA의 투입량을 1, 2, 5, 10 wt.% 로 달리하면서 투입하여 제조하였으며, FT-IR과 $^1H$ NMR 분석을 통하여 성공적으로 PP에 IA가 그래프트 되었음을 확인하였다. 이 중 그래프트율이 1% 로 가장 높게 나타난 PP-g-IA 상용화제를 PP/EVOH 블렌드 연구에 적용하였다. 신규 상용화제가 적용된 PP/EVOH 블렌드는 SEM을 이용하여 모폴로지를 관찰하였고, DSC 와 UTM를 이용하여 열적 기계적 특성을 분석하였다. 분석 결과, PP-g-IA 상용화제는 PP/EVOH 블렌드의 계면접착력을 향상시키는 것으로 나타나 상용화제로써의 유효성이 확인되었다.

• 한국의류산업학회지
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• 제16권3호
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• pp.456-461
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• 2014

The objective of this study is to give PP(polypropylene) fabric a good affinity for water. Oxygen plasma was treated to PP fabrics in a commercial glow discharge reactor with different RF power, discharge pressure, and reaction time. The PP fiber surfaces were characterized by the measurement of contact angle and ESCA. A JEOL scanning electron microscope was used to observe the surface morphology of fibers. The spontaneous water uptake amount of PP fabrics was determined by the demand wettability test. To determine the effect of aging on the surface properties of $O_2$ plasma treated PP, all the above measurements of the samples were carried out after 1, 7, 30, 60, and 150 days. The results are as follows. The PP fiber surfaces treated by $O_2$ plasma treatment have a chemical composition that consisted of various oxygen containing polar groups. Consequently, the contact angles of the treated PP fibers decreased, which improved the water uptake rate of PP fabrics. Surface roughness of the treated PP affected the fabric wettabiity as well. Wettability of the treated PP decreased and leveled off with aging. The $O_2$ plasma treatment is a simple and effective method to increase the water uptake rate of PP fabrics.

• BMB Reports
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• 제28권4호
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• pp.331-335
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• 1995

Simian virus 40 (SV40) small-t antigen (small-t) has been known to regulate the activity of a cellular enzyme, protein phosphatase 2A (PP2A), composed of A. B, and C subunits, via binding to the A subunit In the study presented here, the stoichiometry of the binding of small-t to PP2A was determined to be 1: 1. It was also shown that small-t binds to the AC form of PP2A with a higher apparent affinity than it binds to the free A subunit. We also characterized the interaction of PP2A with wild-type and various mutant small-ts. A single-point mutant (Val134Met) and a double-point mutant (Trp147Gly;Leu152 Pro) of small-t exhibited 3-fold and 5-fold lower potencies in inhibiting PP2A activity. respectively. This suggests that the region around amino acids between 134 and 152 of small-t might be important in regulating the enzyme activity of PP2A.

• 대한한방소아과학회지
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• 제14권2호
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• pp.33-46
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• 2000

It has long been known that Jahage(紫河車) extracts of Placenta hominis are effective for immunological and vascular diseases in human body and thus, was used a major constituent of traditional oriental medicines. From full-term human placenta, we have purified a new type anticoagulant protein, PP27, using different chromatographic techniques of a phenyl TSK gel 650M column, DEAE, HA and Mono-Q columns. PP27 showed single band on SDS-PAGE with a molecular mass (Mr) of 27 kDa under denaturing conditions and a calibrated Sepharose 4B column chromatography indicated a molecular mass of 23 kDa, indicating that the value is similar to those of other PP4 enzyme reported to date. Isoelectric point of PP27 was p15.2. The protein was found to inhibit the coagulation time in a concentration-dependent manner. PP27 was acted as a vascular anticoagulant of annexin type, inhibits the blood clotting process by binding of the essential lipids in a reaction which is dependent on $Ca2^+$ ions. In the presence of $Ca2^+$ ions, PP27 combines with platelet membranes neutralizing their procoagulant effect. Coagulation triggered by the addition of thromboplastin/ lipid- mixtures is extinguished by PP27.