• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.2
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• pp.85-94
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• 2002

Antibodies raised against the purified p-subunit of $\beta$-conglycinin were used in immunohistochemical studies to monitor the pattern of $\beta$-conglycinin mobilization in the cotyledons during soybean [Glycine max (L.) Merr.] seed germination. Western blot analysis revealed that the break down of the $\beta$-subunit of $\beta$-conglycinin commenced as early as 2 days after seed imbibition (DAI). Concurrent with the degradation of the $\beta$-subunit of $\beta$-conglycinin, accumulation of 48, 28, and 26 kD proteolytic intermediates was observed from 2 to 6 DAI. Western blot analysis also revealed that the acidic subunit of glycinin was mobilized earlier than the basic subunit. The basic glycinin subunit was subjected to proteolysis within 2 DAI resulting in the appearance of an intermediate product approximately 2 kD smaller than the native basic glycinin subunit. In contrast to the major seed storage proteins, lipoxygenase was subjected to limited proteolysis and was detected even after 8 DAI. The first sign of $\beta$-conglycinin breakdown was observed near the vascular strands and proceeded from the vascular strands towards the epidermis. Protein A-gold localization studies using thin sections of soybean cotyledons and antibodies raised against the $\beta$-subunit of $\beta$-conglycinin revealed intense labeling over protein bodies. A pronounced decrease in the protein A-gold labeling intensity over protein bodies was observed at later stages of seed germination. The protein bodies, which were converted into a large central vacuole by 8 DAI, contained very little 7S protein as evidenced by sparse protein A-gold labeling in the vacuoles.

• Journal of agriculture & life science
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• v.43 no.5
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• pp.39-42
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• 2009

Soybean is an important sources of plant proteins for human and animal nutrition. The use of soybean proteins has been expanded in the food industry due to their excellent nutritional benefits. But, Soybeans contain allergenic proteins that cause allergies to sensitive individuals. ${\beta}$-conglycinin(7S globulin) and glycinin(11S globulin) are the major components of storage protein in soybean. ${\beta}$-conglycinin consists of three subunits, ${\alpha}^{\prime}$, ${\alpha}$, ${\beta}$ and exhibits poorer nutritional and food processing properties than glycinin. There is a great deal of interest in the development of soybean lines with reduced amounts of ${\beta}$-conglycinin. The objective of this study was to determine the inheritance of ${\alpha}^{\prime}$-subunit protein in 7S globulin. F2 population was developed from the cross of "Jinpumkong2ho"(${\alpha}^{\prime}$-subunit presence) and PI506876(${\alpha}^{\prime}$-subunit absence) parent. Total 98 of F2 seeds were obtained and analyzed for the segregation of ${\alpha}^{\prime}$-subunit protein by SDS-PAGE. Among 98 F2 seeds, 70 F2 seeds showed ${\alpha}^{\prime}$-subunit protein and 28 F2 seeds did not show ${\alpha}^{\prime}$-subunit protein. The segregation ratios of 3 : 1 for presence and absence of ${\alpha}^{\prime}$-subunit protein were observed(${\chi}^2=0.667$, P=0.414). These data indicate that presence and absence of ${\alpha}^{\prime}$-subunit protein is controlled by a single major gene and might be useful for strain selection of 7S protein reduced soybean.

• BMB Reports
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• v.39 no.6
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• pp.671-676
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• 2006

The holoenzyme of protein phosphatase (PP) from tulip petals was purified by using hydrophobic interaction, anion exchange and microcystin affinity chromatography to analyze activity towards p-nitrophenyl phosphate (p-NPP). The catalytic subunit of PP was released from its endogenous regulatory subunits by ethanol precipitation and further purified. Both preparations were characterized by immunological and biochemical approaches to be PP2A. On SDS-PAGE, the final purified holoenzyme preparation showed three protein bands estimated at 38, 65, and 75 kDa while the free catalytic subunit preparation showed only the 38 kDa protein. In both preparations, the 38 kDa protein was identified immunologically as the catalytic subunit of PP2A by using a monoclonal antibody against the PP2A catalytic subunit. The final 623- and 748-fold purified holoenzyme and the free catalytic preparations, respectively, exhibited high sensitivity to inhibition by 1 nM okadaic acid when activity was measured with p-NPP. The holoenzyme displayed higher stimulation in the presence of ammonium sulfate than the free catalytic subunit did by protamine, thereby suggesting different enzymatic behaviors.

• The Korean Journal of Physiology and Pharmacology
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• v.18 no.2
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• pp.155-161
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• 2014

Overexpression of amyloid precursor protein with the Swedish mutation causes abnormal hyperphosphorylation of the microtubule-associated protein tau. Hyperphosphorylated isoforms of tau are major components of neurofibrillary tangles, which are histopathological hallmarks of Alzheimer's disease. Protein phosphatase 2A (PP2A), a major tau protein phosphatase, consists of a structural A subunit, catalytic C subunit, and a variety of regulatory B subunits. The B subunits have been reported to modulate function of the PP2A holoenzyme by regulating substrate binding, enzyme activity, and subcellular localization. In the current study, we characterized regulatory B subunit-specific regulation of tau protein phosphorylation. We showed that the PP2A B subunit PPP2R2A mediated dephosphorylation of tau protein at Ser-199, Ser-202/Thr-205, Thr-231, Ser-262, and Ser-422. Down-regulation of PPP2R5D expression decreased tau phosphorylation at Ser-202/Thr-205, Thr-231, and Ser-422, which indicates activation of the tau kinase glycogen synthase kinase 3 beta ($GSK3{\beta}$) by PP2A with PPP2R5D subunit. The level of activating phosphorylation of the $GSK3{\beta}$ kinase Akt at Thr-308 and Ser-473 were both increased by PPP2R5D knockdown. We also characterized B subunit-specific phosphorylation sites in tau using mass spectrometric analysis. Liquid chromatography-mass spectrometry revealed that the phosphorylation status of the tau protein may be affected by PP2A, depending on the specific B subunits. These studies further our understanding of the function of various B subunits in mediating site-specific regulation of tau protein phosphorylation.

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.2
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• pp.163-168
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• 2002

We report for the first time the cDNA sequence encoding a ferritin subunit from the spiders Araneus ventricosus. The complete cDNA sequence of A. ventricosus ferritin subunit comprised 516 bp with 172 amino acid residues. The A. ventricosus ferritin subunit cDNA contained a conserved iron responsive element sequence in the 5 untranslated region. An alignment of the deduced protein sequence of the A. ventricosus ferritin subunit gene to that of other heavy chain ferritin molecules showed that A. ventricosus ferritin subunit is most similar to the great pond snail, Lymnaea stagnalis, ferritin with 70.2% of protein sequence identity.

• Archives of Pharmacal Research
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• v.19 no.6
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• pp.502-506
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• 1996

Protein X is one of the subunits of pyruvate dehydrogenase complex. The biological role of this protein has not been fully elucidated, mainly because of the difficulty in its dissociation from the tightly bound dihydrolipoamide acetyltransferase-protein X subcomplex. We have found that the detachment of protein X from acetyltransferase subunit can be easily accomplished by the cycles of freezing and thawing proces. Several lines of evidence including sodium dodecyl sulfate-polyacrylamide gel electrophoresis, N-terminal amino acid sequence analysis and acetylation with $[2^{14}C]$ pyruvate confirmed that the purified protein is protein X. The purified intact form of protein X was acetylated by $[2^{14}C]$ pyruvate in the presence of py-ruvate dehydrogenase subunit.The acetylation efficiency of this protein was lower than that of acetyltransferase and was not affected by the presence of acetyltransferase.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.4
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• pp.291-299
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• 2000

Morphine or butorphanol was continuously infused into cerebroventricle (i.c.v.) with the rate of $26\;nmol/{\mu}l/h$ for 3 days, and the withdrawal from opioid was rendered 7 hrs after the stopping of infusion. The expression of physical dependence produced by these opioids was evaluated by measuring the naloxone-precipitated withdrawal signs. The withdrawal signs produced in animals dependent on butorphanol (kappa opioid receptor agonist) were similar to those of morphine (mu opioid receptor agonist). Besides the behavioral modifications, opioid withdrawal affected G protein expression in the central nervous system. The G-protein ${\alpha}-subunit$ has been implicated in opioid tolerance and withdrawal. The effects of continuous infusion of morphine or butorphanol on the modulation of G protein ${\alpha}-subunit$ mRNA were investigated by using in situ hybridization study. In situ hybridization showed that the levels of $G\;{\alpha}s$ and $G\;{\alpha}i$ were changed during opioid withdrawal. Specifically, the level of $G\;{\alpha}s$ mRNA was decreased in the cortex and cerebellar granule layer during the morphine and butorphanol withdrawal. The level of $G\;{\alpha}i$ mRNA was decreased in the dentate gyrus and cerebellar granule layer during the morphine withdrawal. However, the level of $G\;{\alpha}i$ mRNA was significantly elevated during the butorphanol withdrawal. These results suggest that region-specific changes of G protein ${\alpha}-subunit$ mRNA were involved in the withdrawal from morphine and butorphanol.

• Parasites, Hosts and Diseases
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• v.37 no.4
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• pp.277-283
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• 1999

To investigate the development of a subunit vaccine against theileriosis in cattle, the DNA fragments encoding piroplasm surface protein (p33) of Theileria sergenti of a Korean isolate were expressed in baculoviruses. The expressed p33 was characterized by indirect fluorescent antibody (IFA) and western blotting analysis. The expression of p33 was mainly detected on the surface of infected Sf21 cells by IFA. The immunoblotting analysis revealed the presence of a same molecular weight protein band of p33. The antigenicity of expressed polypeptide was further examined through the inoculation of a guinea pig. The sera of guinea pigs immunized with p33 expressed cell Iysate showed similar fluorescent antibody patterns and reacted with the same molecular weight protein of T. sergenti in immunoblotting analysis, thus indicating that this protein can be a promising candidate for a subunit vaccine in the future.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.260-260
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• 1994

Mammalian pyruvate dehydrogenase complex(PDC) enzyme consists of multiple oopies of three major oligomeric enzymes-El, E2 E3. And protein X is one of the enzymatic constituents which is tightly bound to E2 subunit This complex enzyme is responsible for the oxidative decarboxylation of pyruvate producing of acetyl CoA which is a key intermediate for the entry of carbohydrates into the TCA cycle for its complete metabolic conversion to CO$_2$. And the overall activity of the complex enzyme is regulated via covalent nodification of El subunit by a El specific phosphatase ad kinase. Protein X has lipoyl moiety that undergoes reduction and acetylation during ezymatic reaction and has been known h be involved in the binding of E3 subunit to E2 core and in the regulatory activity of kinase. The purification of protein X has not been achieved majorly because of its tight binding to E2 subunit The E2-protein X subcomplex was obtained by the established methods and the detachment of protein X from E2 was accomplished in the 0.1M borate buffer containing 150mM NaCl. During the storage of the subcomplex in frozen state at -70$^{\circ}C$, the E2 subunit was precipitated and the dissociated protein X was obtained by cntrifegation into the supernatant The verification of protein X was accomplished by (1)the migration on SDS-PAGE, (2)acetylation by 〔2$\^$-l4/C〕 pyruvate, and (3)internal amino acid sequence analysis of tryptic digested enzyme.

• Korean Journal of Breeding Science
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• v.42 no.1
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• pp.35-39
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• 2010

Soybean proteins are widely used for human and animal feed in the world. ${\beta}$-conglycinin protein exhibits poor nutritional and food processing properties and Kunitz trypsin inhibitor (KTI) protein is a main anti-nutritional factor in soybean seed. The objective of this research was to identify the inheritance of $cgy_1$ gene and ti gene for the improvement of soybean cultivar with no KTI proteins and low amount of ${\beta}$-conglycinin. $F_2$ population was made by crossing between "Gaechuck2ho" (${\alpha}^{\prime}$-subunit present $Cgy_1Cgy_1$, KTI protein absent titi) and PI506876 (${\alpha}^{\prime}$-subunit absent $cgy_1cgy_1$, KTI protein present TiTi) parent. A total of 434 $F_2$ seeds were obtained and analyzed for the segregation of ${\alpha}^{\prime}$-subunit protein and KTI protein using SDS-PAGE. The segregation ratio of 3 : 1 for $Cgy_1$ locus (310 $Cgy_1$_ : 124 $cgy_1cgy_1$) and Ti locus (339 Ti_ : 95 titi) were observed. Segregation ratios of 9 : 3 : 3 : 1 (241 $Cgy_1$_Ti_: 69 $Cgy_1$_titi: 98 $cgy_1cgy_1$Ti_: 26 $cgy_1cgy_1titi$) between $Cgy_1$ gene and Ti gene in $F_2$ seeds were also observed (${\chi}^2= 5.367$, P = 0.10 - 0.20). This data showed that $Cgy_1$ gene was inherited independently with the Ti gene in soybean. These results will be useful in breeding program for selecting the line that does not exhibit or lacks both ${\alpha}^{\prime}$-subunit protein and KTI protein in soybean.