• 대한의생명과학회지
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• 제12권4호
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• pp.385-391
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• 2006

Heterotrimeric GTP binding proteins (G proteins) mediate signals generated by neurotransmitters and hormones Among G proteins, Go is found in a large quantity in brain and growth cone membranes of neurons. In spite of its abundance in neurons, the role of Go is not fully understood. In our previous study, we identified promyelocytic leukemia zinc finger protein (PLZF) as an interacting partner of alpha subunit of Go ($Go{\alpha}$) and confirmed their interaction employing several biochemical assays. To date, it is reported that PLZF functioned as a cell growth suppressor and a transcription repressor. To determine effect of $Go{\alpha}$ and PLZF interaction on the cellular function of PLZF, we performed luciferase reporter gene assay and BrdU incorporation assay. Co-expression of $Go{\alpha}$ and PLZF synergistically increased the effect of PLZF alone. These results suggest that $Go{\alpha}$ may act as cellular activator of PLZF. This novel feature of Go may provide insights into understanding diverse role of Go-coupled receptor as well as its cellular actions.

• 한국식품과학회지
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• 제29권5호
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• pp.1067-1070
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• 1997

Chelating sepharose fast flow gel에 $Cu^{2+}$을 고정화시키고 이들과 단백질과의 친화력 정도에 의해서 용출용매를 통해 단백질을 분획하는 방식의 IMAC법을 이용하여 소의 혈장단백질로부터 IgG의 분리를 시도하였다. 대부분의 혈장단백질은 1차(0.01 M $Na_2HPO_4$, 0.5 M NaCl, pH 4.0)와 2차 용출용매(0.01 M imidazol)에 의하여 용출되었으며 역상 chromatography를 이용하여 각 분획의 단백질조성을 조사한 결과, 1차 용출용매에 의해서는 주로 albumin이, 그리고 2차 용출용매에 의해서는 IgG와 transferrin 등이 IMAC column으로부터 용출되었다. 2차 용출용매에 의해 얻어진 분획으로부터 분자량 100 kD이상의 단백질을 한외여과장치를 이용하여 농축하였을 때, IgG가 효과적으로 분리 정제 되었다.

• Radiation Oncology Journal
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• 제35권3호
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• pp.281-288
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• 2017

Purpose: The serum carcinoembryonic antigen (CEA) level has been recognized as a prognostic factor in colorectal cancer, and associated with response of rectal cancer to radiotherapy. This study aimed to identify CEA-interacting proteins in colon cancer cells and observe post-irradiation changes in their expression. Materials and Methods: CEA expression in colon cancer cells was examined by Western blot analysis. Using an anti-CEA antibody or IgG as a negative control, immunoprecipitation was performed in colon cancer cell lysates. CEA and IgG immunoprecipitates were used for liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. Proteins identified in the CEA immunoprecipitates but not in the IgG immunoprecipitates were selected as CEA-interacting proteins. After radiation treatment, changes in expression of CEA-interacting proteins were monitored by Western blot analysis. Results: CEA expression was higher in SNU-81 cells compared with LoVo cells. The membrane localization of CEA limited the immunoprecipitation results and thus the number of CEA-interacting proteins identified. Only the Ras-related protein Rab-6B and lysozyme C were identified as CEA-interacting proteins in LoVo and SNU-81 cells, respectively. Lysozyme C was detected only in SNU-81, and CEA expression was differently regulated in two cell lines; it was down-regulated in LoVo but up-regulated in SNU-81 in radiation dosage-dependent manner. Conclusion: CEA-mediated radiation response appears to vary, depending on the characteristics of individual cancer cells. The lysozyme C and Rab subfamily proteins may play a role in the link between CEA and tumor response to radiation, although further studies are needed to clarify functional roles of the identified proteins.

• 대한의생명과학회지
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• 제12권4호
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• pp.405-411
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• 2006

Heterotrimeric GTP binding proteins (G proteins) mediate signal transduction generated by neurotransmitter and hormones. Among G-proteins, Go is classified as a member of the Go/Gi family and the most abundant heterotrimeric G protein in brain. Most of the mechanistic analyses on the activation of Go indicated its action to be mediated by the $G{\beta}{\gamma}$ dimer because downstream effectors for its ${\alpha}$ subunit have not been clearly defined. To determine the downstream effectors of alpha subunits of Go ($Go{\alpha}$), we used yeast two-hybrid system to screen $Go{\alpha}$ interacting partners in cDNA library from the human brain. A brain specific high mobility group box containing protein (BHX), A possible transcription factor, was identified as a $Go{\alpha}$ interacting protein. We confirmed interaction between $Go{\alpha}$ and BHX employing in vitro affinity binding assay. Moreover, active form of $Go{\alpha}$ preferentially interacts with BHX than inactive farm. Our findings indicate that $Go{\alpha}$ could modulate gene expression via interaction with BHX during neuronal or brain development.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2003년도 정기총회 및 학술발표회
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• pp.59-59
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• 2003

Serotonin (5-HT; 5-hydroxytryptamine) exerts multiple effects on central nervous system as well as behaviors such as mood and appetite. The signaling of serotonin is mediated by 7 families of serotonin receptors, designated 5-HT$_1$ to 5-HT$_{7}$. Six families of this receptor are G-protein coupled 7TM receptors, and the third intracellular loop of these receptors is proposed to interact with specific types of G-proteins. To investigate the specific interaction between the third intracellular loop of 5-HT$_{6}$ with G$\square$s, we have constructed a chimera protein that represent the third intracellular loop of 5-HT$_{6}$ within a leucine zipper motifs, In addition an alpha subunit of human G-protein that interact with 5-HT$_{6}$ was cloned into a bacterial expression vector. The two proteins were expressed in E. coli and purified in homogeneity. The interaction of the prepared proteins was examined by ELISA assay. The affinity between the two proteins and effect of insertion mutations were discussed.ussed.d.

• The Plant Pathology Journal
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• 제33권6호
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• pp.614-618
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• 2017

The root-knot nematode Meloidogyne incognita infects a variety of plants, including Arabidopsis thaliana. During migration, root-knot nematodes secrete different proteins to modify cell walls, which include pectolytic enzymes. However, the contribution of host cell wall proteins has not been described during this process. The function of two DUF642 cell wall proteins, BIIDXI (BDX, At4g32460) and TEEBE (TEB, At2g41800), in plant development could be related to the regulation of pectin methyl esterification status in the cell walls of different tissues. Accordingly, the expression of these two genes is up-regulated by auxin. BDX and TEB were highly induced during early M. incognita inoculation. Moreover, cell wall localization of the proteins was also induced. The cell wall localization of BDX and TEB DUF642 proteins during M. incognita early inoculation suggested that these two proteins could be involved in the regulation of the degree of pectin methylation during cell separation.

• 원예과학기술지
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• 제29권4호
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• pp.306-310
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• 2011

본 연구는 3-4년생인 '부유' 감나무를 이용하여 정상적인 착과수와 결실 후 어린 과실을 따버린 제과수의 수체 부위별 질소화합물 분배 비율의 변화를 조사함으로써 저장양분의 축적 그리고 다음해 새로운 생장에 이들 저장양분의 재이용 관계를 구명하였다. 6월 15일부터 11월 1일까지 아미노산은 착과수의 영구기관에서 변화의 일관성이 없는 반면 제과수에서는 아미노산이 현저히 증가하였다. 착과수와 비교하면, 제과수의 영구기관에 축적된 주당 아미노산 함량이 3년생은 1.66g, 4년생은 3.48g 많았다. 이 기간 동안 착과수에서는 증가한 총 단백질의 50% 이하가 영구기관으로 분배되었으나 제과수에서는 그 비율이 90% 이상이었고, 특히 뿌리로 분배된 비율이 3년생은 94%, 4년생은 76%에 달하여 뿌리의 단백질 축적이 현저한 것을 알 수 있었다. 착과수의 영구기관에 축적된 주당 단백질 함량과 비교하면 제과수의 3년생은 1.64g, 4년생은 2.58g이 많았다. 이 기간 동안 질소화합물이 착과수의 잎에서 0.50-0.56g이 감소하였고, 과실에서 0.66-0.78g이 증가하였다. 이듬해 신초생장기 동안 아미노산은 전년도 착과수와 제과수의 영구기관에서 모두 감소하였다. 단백질은 전년도 제과수의 뿌리에서 특히 감소하였다. 새로운 생장 부위의 아미노산과 단백질은 전년도 제과수에서 높은 것으로 나타났다. 제과수는 착과수보다 뿌리를 주축으로 하는 영구기관에 더 많은 질소화합물을 축적함으로써 다음해의 생장과 결실에 기여할 수 있을 것으로 생각한다.

• Journal of Plant Biology
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• 제39권2호
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• pp.85-92
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• 1996

Small GTP-binding proteins are divided into three major group: Ras, Rho and Ypt/Rab. They have the conserved regions designed G1 to G5 that are critical in GDP/GTP exchange, GTP-induced conformational change and GTP hydrolysis. We isolated and characterized genomic DNA or cDNAfragments encoding G1 to G3 domains of small GTP-binding protein Rab and Rho from several plant species using two different PCR-based cloning strategies. Seven rab DNA fragments were isolated from 4 different plants, mung-bean, tobacco, rice and pepper using two degenerate primers corresponding to the GTP-binding domain G1 and G3 in small GTP-binding proteins. The amino acid sequences among these rab DNA fragments and other known small GTP-binding proteins shows that they belong to the Ypt/Rab family. Six rho DNA fragments were isolated from 5 different plants, mung-bean, rice, Arabidopsis, Allium and Gonyaulax using the nested PCR method that involves four degenerate primers corresponding to the GTP-binding domain G1, G3 and G4. The rho DNA fragments cloned show more than 90% homology to each other. Sequence comparison between plant and other known Rho family genes suggests that they are closely related (67 to 82% amino acid identity). Sequence analysis and southern blot analysis of rab and rho in mung-bean suggest than thses genes are encoded by multigene family in mung-bean.

• 한국식품조리과학회지
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• 제10권3호
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• pp.254-259
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• 1994

Meat provides high quality proteins, lipids, minerals and vitamins. The meat protein is especially high in essential amino acids that are crucial for human health, growth & development and for the formation of enzymes, hormones and antibodies. Relatively cheap and nutritionally sound vegetable proteins that are similar to animal proteins are being developed to replace the animal proteins in texture, nutrition and food characteristics. In this study a nutritionally sound meat lipid replacing food Oatrim that has been produced by converting oat starch into maltodextrin by ${\alpha}$-amylase, have been partially substituted for beef and general component analysis, texture measurement and sensory tests have been conducted. The results are 1. Water content of the non-treated (0% treated) was 67.1% and the treated (10% treated) was 77%. The treated showed better water holding capacity. 2. Protein content of the non-treated was 21.2 g/100 g; the 4% treated, 18.4 g/100 g; the 6% treated, 18.2 g/100 g; the 8% treated, 17.2 g/100g; and the 10% treated, 16.0 g/100 g. The protein content tended significant. 3. Amino acid analysis results showed that glutamic acid content was the highest in Oatrim and as its amino acid make up is exellent, it is valuable as a fine low fat protein food. 4. Sensory tests show that the increased Oatrim content increased the appearance quality but food characteristics were high only in the 4% and 6% treated groups, indicating that the replacement ratio should not exceed 10%. 5. Texture measurement analysis results show that the higher the replacement content, lower the springness, cohesiveness, hardness, chewiness and gumminess, resulting in relatively soft overall texture. However, in order to better the food characteristics, more studies must be continuously done, and so by being able to increase vegetable substitution over meat, it may be able to contribute to the prevention of adult disease.

• Asian-Australasian Journal of Animal Sciences
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• 제15권3호
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• pp.340-345
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• 2002

In this experiment, oocytes were collected from goat ovaries available in slaughterhouse by follicle puncture method. Morphologically culturable type of oocytes which having compact, multilayered cumulus granulosa cell complex and evenly granulated cytoplasm, was separated under a stereozoom microscope. Oocytes were washed thoroughly in maturation medium containing TCM-199, $1{\mu}g/ml$ estradiol-$17{\beta}$, 0.5 ${\mu}g/ml$ FSH, $100{\mu}g/ml$ LH, 3 mg/ml BSA and 10% estrus goat serum. Washed oocytes were cultured into maturation medium on granulosa cell monolayer. Culture plate was then kept into $CO_2$ incubator at $38{\pm}1^{\circ}C$, maximum humidity and 5% $CO_2$ for 18 h. After maturation the oocytes were washed thoroughly with maturation medium containing polyvinyl alcohol (PVA) without serum and BSA and further cultured for 12 h for secretory proteins of oocytes. PVA medium was collected, pooled and concentrated by 5000 cut off centrisart. Secretory proteins were separated on 12.5% SDS-PAGE. A total number of 3.41 oocytes per ovary were obtained and 2.17 culturable oocytes per ovary were cultured into maturation medium. After 18 h of maturation, 4,567 oocytes (1.82 oocytes per ovary) were further cultured into serum and BSA free PVA medium for its secretory proteins. Four secretory proteins of oocytes with approximately molecular weight of 45, 55, 65 and 95 kDa were obtained on SDS-PAGE in silver staining and three proteins with approximately molecular weight of 45, 55 and 65 kDa in Coomassie brilliant blue staining. In conclusion, four secretory proteins with approximately molecular weight of 45, 55, 65 and 95 kDa was obtained from in vitro cultured oocytes of goats.