• Journal of Life Science
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• v.27 no.3
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• pp.370-381
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• 2017

Protein dephosphorylation is important for cellular regulation, which is catalyzed by protein phosphatases. Among protein phosphatases, carboxy-terminal domain (CTD) phosphatases are recently emerging and new functional roles of them have been revealed. There are 7 CTD phosphatases in human genome, which are composed of CTD phosphatase 1 (CTDP1), CTD small phosphatase 1 (CTDSP1), CTD small phosphatase 2 (CTDSP2), CTD small phosphatase-like (CTDSPL), CTD small phosphatase-like 2 (CTDSPL2), CTD nuclear envelope phosphatase (CTDNEP1), and ubiquitin-like domain containing CTD phosphatase 1 (UBLCP1). CTDP1 dephosphorylates the second phosphor-serine of CTD of RNA polymerase II (RNAPII), while CTDSP1, STDSP2, and CTDSPL dephosphorylate the fifth phosphor-serine of CTD of RNAPII. In addition, CTDSP1 dephosphorylates new substrates such as mothers against decapentaplegic homologs (SMADs), cell division cycle-associated protein 3 (CDCA3), Twist1, tumor-suppressor protein promyelocytic leukemia (PML), and c-Myc. CTDP1 is related to RNA polymerase II complex recycling, mitosis regulation and cancer cell growth. CTDSP1, CTDSP2 and CTDSPL are related to transcription factor recruitment, tumor suppressor function and stem cell differentiation. CTDNEP1 dephosphorylates LIPIN1 and is related to neural tube formation and nuclear envelope formation. CTDSPL2 is related to hematopoietic stem cell differentiation. UBLCP1 dephosphorylates 26S proteasome and is related to nuclear proteasome regulation. In conclusion, noble roles of CTD phosphatases are emerging through recent researches and this review is intended to summarize emerging roles of CTD phosphatases.

• Journal of Life Science
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• v.18 no.1
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• pp.114-119
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• 2008

The molecular machinery controlling cell cycle is centered around the regulation of the activity of maturation-promoting factor (MPF), a complex composed of a catalytic Cdc2 and the cyclinB regulatory subunit. Cdc2 kinase is inactivated by phosphorylation of inhibitory kinase, Wee1. It has been known that there are three different Wee1 kinases in the mammalian cell, Wee1A, Wee1B and Myt1. To investigate the regulatory mechanism of Wee1 kinases, the phosphorylation and degradation of Wee1A and Wee1B were checked in the Xenopus oocyte cell cycle. When Wee1 kinases were injected into frog oocyte, Wee1B was more stable than Wee1A. Wee1A and Wee1B kinase were phosphorylated by many kinases such as PKA and Akt. The roles of amino or carboxyl terminal in mouse Wee1A or Wee1B kinase were investigated using chimeric constructs. The degree of protein phosphorylation, degradation and cell cycle progression were different between chimeric constructs. The amino domain of Wee1A was implicated in the protein phosphorylation and degradation while amino domain of Wee1B and carboxyl domain of Wee1A were involved in the activity regulation. These results suggested that the domains of Wee1 kinase have different and significant roles in regulating the Wee1 kinases in the cell cycle progression.

• Journal of Plant Biology
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• v.35 no.4
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• pp.333-338
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• 1992

Ginkgo (Ginkgo biloba L.) seeds were analyzed to determine the level of soluble sugars and insoluble starch during germination. Also the activities of the hydrolytic enzymes such as amylase, invertase and phosphatase were compared. As amylase activity was sharply increased, significant decline of starch was observed in the female gametophyte and increase of soluble sugars occurred concurrently. Invertase activity was gradually increased in cotyledon and radicle, while it was very low in dry seeds. In addition, phosphatase activity was variable only in radicle, and acid phosphatase showed higher activity than alkaline phosphatase.hatase.

• Journal of Periodontal and Implant Science
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• v.35 no.1
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• pp.133-152
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• 2005

1. 목적 Prostaglandin은 치주질환과 관련된 국소적 골 대사에 중요한 역할을 한다. ${\Delta}^{12}PGJ_2$는 생체 내에서 혈장의 존재 하에 형성되는 천연 $PGD_2$ 대사산물이며 peroxisome- proliferator에 의해 활성화되는 감마 수용체 (PPAR ${\Gamma}$)에 대해 높은 친화성을 갖는 리간드로서 핵 수용체군에 속하는 전사조절인자이다. 이 연구의 목적은 골화 과정에서 ${\Delta}^{12}PGJ_2$의 역할을 규명하기 위해, 조골세포주의 증식과 분화에 미치는 영향과 그에 관련된 세포기전을 조사하는 데에 있다. 2. 방법 인간 골육종세포주인 Saos-2 (ATCC.HTB 85)와 쥐의 조골세포주 (MC3T3-E1)를 배양한 후 실험군에 농도가 각각 $10^{-5}$, $10^{-6}$, $10^{-7}$, $10^{-8}$, $10^{-9}$ 몰인 ${\Delta}^{12}PGJ_2$와 ciglitazone (합성 PPAR 감마 길항체)를 첨가하였다. 조골세포에서 PPAR 감마의 발현을 관찰하기 위해 역전사효소-중합효소연쇄반응(RT-PCR)을 특정한 primer를 이용하여 시행하였다. 세포 증식은 1일, 2일, 3 일째에 MIT 분석법으로 측정하였고, 2 일째에 알칼리성 인산효소 (ALPase) 생산을 측정하였다. 위의 결과에서 얻은 적정한 농도에서 다양한 조골세포 분화의 표지자들-제 1 형 교원질, 알칼리성 인산효소, osteopontin 및 bone sialoprotein-에 대한 간이 정량적 역전사효소-중합효소연쇄반응 (semiquantitative RT-PCR)을 실시하였으며 골결절 형성에 대한 효과를 알아보고자 석회화 분석도 시행하였다. 3. 결과 ${\Delta}^{12}PGJ_2$와 ciglitazone 모두 Saos-2 세포주의 증식을 촉진시켰다 .$10^{-8}$ 몰의 ${\Delta}^{12}PGJ_2$와 $10^{-6}$몰의 ciglitazone을 첨가한 실험군을 대조군과 비교했을 때, 시간에 비례하여 세포 증식률이 증가되었다. 알칼리성 인산효소의 활성화 검사에서도 증식률에서와 유사한 결과를 보여주었다. 간이 정량적 RT-PCR에서는 ${\Delta}^{12}PGJ_2$로 처리한 군의 경우 제 1 형 교원질, 알칼리성 인산효소, osteopontin, 그리고 bone sialoprotein의 상대적 mRNA 수준이 유의하게 높았다. 석회화 분석에서는 MC3T3-E1 세포를 $10^{-6}$ 몰의 ${\Delta}^{12}PGJ_2$로 처리한 군과 $10^{-5}$ 몰의 ciglitazone으로 처리한 군에서 현저한 골결절 형성을 보였다. 이러한 결과들은 ${\Delta}^{12}PGJ_2$가 유용한 골 유도물질이 될 수 있으며 또한 그 작용기전이 PPAR 감마-의존형 경로와 연관되어 있음을 보여준다.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.10a
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• pp.1-29
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• 2004

본 연구에서 저알레르기 처리 공정은 Autoclaving, 가열처리, micro wave, dry heating, 초음파, 효소, 인산염, 천연효소, 가용화, 복합처리 등의 처리 공정으로 하였다. 저 allergy처리에서 allergy가 완전히 억제되는 것은 가열처리를 한 것으로 쇄양 B(추출액+가열 3분), autoclave 처리, micro파 처리, dry heating처리, 복합처리를 했을 때이다. 또한 천연효소(키위)를 침지한 후 tolergen과 같이 3분간 가열했을 때 allergy가 억제되는 것으로 나타났다. 즉 가열처리로 인한 단백질 구조 변성으로 이러한 결과를 보인 것으로 보인다. 인산염의 경우도 어느 정도 억제가 되는 것으로 보이고 있다. 나머지 처리들은 거의 효과를 보이고 있지 않다. 천연효소와 tolergen(쇄양)을 그냥 처리했을 때에는 allergy 억제효과는 없는 것으로 나타났다. 우유의 저 allergy 처리는 효소, autoclave, micro 파, NaOH 처리, 복합처리에서 감소되는 것으로 나타났다. 이러한 결과는 western blotting으로도 확인되었으며 그 억제율 %은 식육에서는 상당한 가열처리를 통하여 알레르기를 감소시킬 수 있는 것을 볼 수 있으며 또한 인산염, 가용화(NaOH처리)도 저 알레르기 효과가 있음을 알 수 있다. 키위, 쇄양 단독 처리 시 저 알레르기 효과가 없지만 약간의 가열을 통하여 알레르기가 감소됨을 알 수 있다. 우유는 효소나 autoclave 처리만이 저 allergy 효과가 각각 28%, 45%로 적게 나타났다. 모든 복합처리의 경우에서는 그 억제율이 41-96%로 높은 효과가 있음을 알 수 있다. 천연효소처리와 인산염 처리된 식육의 전자현미경적 관찰은 control과 비교시 조직의 변화가 없고 둘다 근육 단백질 구조를 분산시키는 것으로 나타났다. 또한 고기를 단계별 복합처리로 저 allergy 처리는 단계별로 점차적으로 allergy가 감소되었다. 즉 단계별로 억제가 안되는 것부터 억제되는 처리를 복합적으로 처리한 것으로 그 단계는 천연효소처리에 인산염 처리, 여기에 초음파 처리, 마지막 단계로 3분 끓이면 억제율이 68%까지 억제되었다. 이는 단일처리시 전혀 억제를 못하는 처리를 단계별로 한 단계씩 더해가면 allergy 억제효과가 나타난다고 할 수 있겠다. 초음파 처리도 역시 저 allergy 처리 공정에 이용될 수 있는데 이것은 그 처리로 인해 새로운 알러젠이 생성될 수도 있다. 또한 복합처리로 allergy를 감소시키면 연속적이고 동시적으로 하기 때문에 원가를 절감할 수 있다.

• Journal of Life Science
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• v.11 no.5
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• pp.489-495
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• 2001

The effect of ozone-water treatment on the morphological change of endosperm cells and the activity of acid phosphatase during Glycine max germination was investigated with electron microscope. Acid phosphatase showed the activity in the cell organelles of germinating endosperm of seed. it's activity occurrs in 12 hrs cultivation after 0.5 ppm ozone-water treatment. As the differentiation of endosperm, reaction products of the acid phosphatase appear to be accumulated invacuole after treatment of ozone-water. This result confirm that acid phosphatase is inveolved in the decomposition and translation of the intracellular storage materials. The characteristics of grganelle in the endosperm cell during germination were discussed.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.114-115
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• 2001

Alloxan은 glucokinase효소가 기질인 glucose결합부위인 -SH기를 경쟁적으로 저해함으로서 glucose의 초기 인산화를 억제하여 당뇨병을 유도시키는 화학물질이다. 본 연구에서는 이제까지의 조직학적이고 혈청학적인 연구에서 한 단계 나아가 효소학적인 측면에서 당대사와 인슐린 분비 조절인자로 알려진 glucokinase와 혈중 당을 조직내로 흡수하여 인산화시키는 효소인 hexokinase에 대한 다시마 열수추출물의 효과를 분석 검토하였다. (중략)

• KSBB Journal
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• v.22 no.5
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• pp.345-350
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• 2007

Phosphosugars are found in all living organisms and are commercially valuable compounds with possible applications in the development of a wide range of specialty chemicals and medicines. In carbohydrate metabolism, fructose 6-phosphate (F6P) is an essential intermediate formed by phosphorylation of 6' position of fructose in glycolysis, gluconeogenesis, pentose phosphate pathway and Calvin cycle. In glycolysis, F6P lies within the glycolysis metabolic pathway and is produced by isomerisation of glucose 6-phosphate. For large-scale production, F6P could be produced from starch using many enzymes such as pullulanase, starch phosphorylase, isomerase and mutase. In enzymatic reactions carried out at high temperatures, the solubility of starch is increased and microbial contamination is minimized. Thus, thermophile-derived enzymes are preferred over mesophile-derived enzymes for industrial applications using starch. Recently, we reported the production of glucose 1-phosphate (G1P) from starch by Thermus caldophilus GK24 enzymes. Here we report the production of F6P from starch through three steps; from starch to glucose 1-phosphate (glucan phosphorylase, GP), then glucose 6-phosphate (phosphoglucomutase, GM) and then F6P (phosphoglucoisomerase, GI). Using 200 L of 1.2% soluble starch solution in potassium phosphate buffer, 1,253 g of G1P were produced. Then, 30% yields of F6P were attained at the optimum reaction conditions of GM : G1 (1 : 2.3), 63.5$^{\circ}C$, and pH 6.85. The optimum conditions were found by response surface methodology and the theoretical values were confirmed by the experiments. The optimum starch concentrations were 20 g/L under the given conditions.

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.935-940
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• 2005

Fluorescence change of coumarin labeled phosphate binding protein (PBP-MDCC) was monitored to measure the amount of released inorganic phosphate ($P_{i}$) during nucleoside triphosphate (NTP) hydrolysis reaction. After purification of PBP-MDCC, fluorescence emission spectra showed that fluorescence responded linearly to $P_{i}$ up to about 0.7 molar ratio of $P_{i}$ to protein. The correlation of fluorescence signal and $P_{i}$ standard was measured to obtain [$P_{i}$] - fluorescence intensity standard curve on the stopped-flow instrument. When T7 bacteriophage helicase, double-stranded DNA unwinding enzyme using dTTP hydrolysis as an energy source, reacted with dTTP, the change of fluorescence was able to be converted to the amount of released $P_{i}$ by the $P_{i}$ standard curve. $P_{i}$ release results showed that single-stranded Ml3 DNA stimulated dTTP hydrolysis reaction several folds by T7 helicase. Instead of end point assay in NTP hydrolysis reaction, real time $P_{i}$-release assay by PBP-MDCC was proven to be very easy and convenient to measure released $P_{i}$.

• The Korean Journal of Mycology
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• v.39 no.1
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• pp.85-87
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• 2011

The opportunistic human pathogen Candida albicans has the ability to convert from yeast-form to pseudohyphal or true hyphal form. The morphological transition is considered as an important virulence factor, because the decrease or lack in dimorphism causes the reduction of virulence. Our previous study revealed that the disruption of dual specificity kinase gene caused the reduction of dimorphism in C. albicans. Therefore we tested the effect of dual specificity kinase in virulence using mouse model. The mean survival time for kinase-defective strains was about 15 days in comparison with those of wild-type, 3.9 days. Moreover the fungal burden on kidneys for kinase-defective strains was decreased by ten-fold than that for wild-type. These results suggest possible involvement of dual specificity kinase in a novel signal transduction pathway for morphological transition and virulence of C. albicans.