40 research outputs found

    A polo-like kinase modulates cytokinesis and flagella biogenesis in Giardia lamblia

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    Background: Polo-like kinases (PLKs) are conserved serine/threonine kinases that regulate the cell cycle. To date, the role of Giardia lamblia PLK (GlPLK) in cells has not been studied. Here, we report our investigation on the function of GlPLK to provide insight into the role of this PKL in Giardia cell division, especially during cytokinesis and flagella formation. Methods: To assess the function of GIPLK, Giardia trophozoites were treated with the PLK-specific inhibitor GW843286X (GW). Using a putative open reading frame for the PLK identified in the Giardia genomic database, we generated a transgenic Giardia expressing hemagglutinin (HA)-tagged GlPLK and used this transgenic for immunofluorescence assays (IFAs). GlPLK expression was knocked down using an anti-glplk morpholino to observe its effect on the number of nuclei number and length of flagella. Giardia cells ectopically expressing truncated GlPLKs, kinase domain + linker (GlPLK-KDL) or polo-box domains (GlPLK-PBD) were constructed for IFAs. Mutant GlPLKs at Lys51, Thr179 and Thr183 were generated by site-directed mutagenesis and then used for the kinase assay. To elucidate the role of phosphorylated GlPLK, the phosphorylation residues were mutated and expressed in Giardia trophozoites RESULTS: After incubating trophozoites with 5 ฮผM GW, the percentage of cells with > 4 nuclei and longer caudal and anterior flagella increased. IFAs indicated that GlPLK was localized to basal bodies and flagella and was present at mitotic spindles in dividing cells. Morpholino-mediated GlPLK knockdown resulted in the same phenotypes as those observed in GW-treated cells. In contrast to Giardia expressing GlPLK-PBD, Giardia expressing GlPLK-KDL was defective in terms of GIPLK localization to mitotic spindles and had altered localization of the basal bodies in dividing cells. Kinase assays using mutant recombinant GlPLKs indicated that mutation at Lys51 or at both Thr179 and Thr183 resulted in loss of kinase activity. Giardia expressing these mutant GlPLKs also demonstrated defects in cell growth, cytokinesis and flagella formation. Conclusions: These data indicate that GlPLK plays a role in Giardia cell division, especially during cytokinesis, and that it is also involved in flagella formation.ope

    ์ง๋ฌด๋งŒ์กฑ์˜ ๋งค๊ฐœํšจ๊ณผ๋ฅผ ์ค‘์‹ฌ์œผ๋กœ

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    ํ•™์œ„๋…ผ๋ฌธ(์„์‚ฌ) -- ์„œ์šธ๋Œ€ํ•™๊ต๋Œ€ํ•™์› : ํ–‰์ •๋Œ€ํ•™์› ๊ณต๊ธฐ์—…์ •์ฑ…ํ•™๊ณผ, 2021.8. ๋ฐ•์ˆœ์• .Techniques, which are recently emphasized from the perspective of human resource management, on the organizational commitment of public corporation employees through job satisfaction mediation: education and training, performance evaluation, position system, promotion system, and performance compensation. The purpose of this study was to analyze and determine whether the mediating effect of job satisfaction showed a difference according to gender. In other words, this study established a research model in which human resource management as an independent variable, job satisfaction as a parameter, and organizational commitment as a dependent variable, under this awareness of the problem, the indirect effect of human resource management on organizational commitment through job satisfaction as a medium. The effect of phosphorus was tested and the mediating effect mediated by gender was analyzed. The subject of this study is public corporation employees working for K Corporation. The survey results of 5,418 people were analyzed. The analysis results and implications are summarized as follows. This study reveals that human resource management not only has a direct effect on organizational commitment, but also has a significant indirect effect through job satisfaction as a mediator, thus showing a big direction that human resource management should be carried out by enhancing the job satisfaction of employees of public enterprises. presented. In addition, by verifying how each human resource management technique has different effects on organizational commitment through mediation of organizational commitment and job satisfaction of employees of public companies, and verifying the mediating effect adjusted to how these effects vary according to gender, the following results are obtained. Specific practical implications were obtained. First, as shown in the study results, the fact that human resource management has a positive (+) effect on job satisfaction and organizational commitment in general is considered to be sufficient incentive to utilize the human resource management system at the management strategic level of public corporations. can Second, it is also significant in that the strength of the relationship that human resource management mediates job satisfaction and leads to organizational commitment varies according to each human resource management technique. It was found that education and training system and personnel evaluation system had more influence on job satisfaction and organizational commitment than other factors. This proves that two factors among the human resource management implemented by public corporations are effective in increasing employee job satisfaction and organizational commitment compared to other factors. Third, it was found that performance compensation items did not have a satisfactory effect on organizational commitment directly among human resource management activities. This is judged to suggest that there is a potential difference of opinion or dissatisfaction with respect to performance compensation. Fourth, it can be seen that the effect of position management on organizational commitment by mediating job satisfaction is greater for women than for men. Through this, it can be seen that it is necessary to establish a balanced position assignment model that can increase the job satisfaction and organizational commitment of female employees in public corporations. If the management of position management of female employees in public corporations is strengthened, this will lead to job satisfaction of female employees. If the value is high, the effect of strengthening organizational commitment will be great. However, it is necessary to keep in mind the following limitations in interpreting the results of this study. Although this study was conducted using the results of a survey conducted by K Corporation, detailed measurement could not be carried out because the measurement items were simply designed for each variable. In future research, it will be possible to develop a scale through detailed questionnaire composition for each variable for more detailed measurement. In addition, the survey on human resource management is a survey data regularly conducted by K Corporation, and there is a possibility that employees will usually give a high score when answering the questionnaire. In addition, it would be more useful if a longitudinal study was added to examine the link between human resource management, job satisfaction, and organizational commitment. In addition, there is a limitation in that the problem of potential endogeneity was not properly controlled in that the analysis was performed using cross-sectional data observed at a specific time point. Therefore, in future studies, it is necessary to alleviate the problem of potential endogeneity by discovering appropriate instrumental variables or conducting analysis using panel data.๋ณธ ์—ฐ๊ตฌ๋Š” ์ตœ๊ทผ ์ธ์ ์ž์›๊ด€๋ฆฌ์˜ ๊ด€์ ์—์„œ ๊ฐ•์กฐ๋˜๊ณ  ์žˆ๋Š” ๊ต์œกํ›ˆ๋ จ, ์„ฑ๊ณผํ‰๊ฐ€, ๋ณด์ง์ œ๋„, ์Šน์ง„์ œ๋„, ์„ฑ๊ณผ๋ณด์ƒ์˜ ๋‹ค์„ฏ ๊ฐ€์ง€ ์ธ์ ์ž์›๊ด€๋ฆฌ ๊ธฐ๋ฒ•์ด ์ง๋ฌด๋งŒ์กฑ๋„์˜ ๋งค๊ฐœ๋ฅผ ํ†ตํ•ด ๊ณต๊ธฐ์—… ์ข…์‚ฌ์ž์˜ ์กฐ์ง๋ชฐ์ž…์— ๋ฏธ์น˜๋Š” ์˜ํ–ฅ์„ ๋ถ„์„ํ•˜๊ณ , ์ด๋Ÿฌํ•œ ์ง๋ฌด๋งŒ์กฑ๋„์˜ ๋งค๊ฐœํšจ๊ณผ๊ฐ€ ์„ฑ๋ณ„์— ๋”ฐ๋ผ ์ฐจ์ด๋ฅผ ๋ณด์ด๋Š”์ง€ ํ™•์ธํ•˜๊ณ ์ž ํ•˜์˜€๋‹ค. ์ฆ‰ ๋ณธ ์—ฐ๊ตฌ๋Š” ์ด๋Ÿฌํ•œ ๋ฌธ์ œ์˜์‹ ํ•˜์— ์ธ์ ์ž์›๊ด€๋ฆฌ๋ฅผ ๋…๋ฆฝ๋ณ€์ˆ˜๋กœ, ์ง๋ฌด๋งŒ์กฑ๋„๋ฅผ ๋งค๊ฐœ๋ณ€์ˆ˜๋กœ, ์กฐ์ง๋ชฐ์ž…์„ ์ข…์†๋ณ€์ˆ˜๋กœ ํ•˜๋Š” ์—ฐ๊ตฌ๋ชจํ˜•์„ ์„ค์ •ํ•˜์—ฌ ์ธ์ ์ž์›๊ด€๋ฆฌ๊ฐ€ ์ง๋ฌด๋งŒ์กฑ๋„๋ฅผ ๋งค๊ฐœ๋กœ ํ•˜์—ฌ ์กฐ์ง๋ชฐ์ž…์— ๋ฏธ์น˜๋Š” ๊ฐ„์ ‘์ ์ธ ์˜ํ–ฅ์„ ๊ฒ€์ •ํ•˜์˜€๊ณ  ์„ฑ๋ณ„์— ์˜ํ•œ ์กฐ์ ˆ๋œ ๋งค๊ฐœํšจ๊ณผ๋ฅผ ๋ถ„์„ํ•˜์˜€๋‹ค. ์—ฐ๊ตฌ๋Œ€์ƒ์€ K๊ณต์‚ฌ์— ๊ทผ๋ฌดํ•˜๋Š” ๊ณต๊ธฐ์—… ์ข…์‚ฌ์ž์ด๋ฉฐ ์ด 5,418๋ช…์˜ ์„ค๋ฌธ์กฐ์‚ฌ ๊ฒฐ๊ณผ๋ฅผ ๋ถ„์„ํ•˜์˜€๋‹ค. ๋ถ„์„ ๊ฒฐ๊ณผ์™€ ์‹œ์‚ฌ์ ์„ ์š”์•ฝํ•˜๋ฉด ๋‹ค์Œ๊ณผ ๊ฐ™๋‹ค. ๋ณธ ์—ฐ๊ตฌ๋Š” ์ธ์ ์ž์›๊ด€๋ฆฌ๊ฐ€ ์กฐ์ง๋ชฐ์ž…์— ์ง์ ‘์ ์ธ ์˜ํ–ฅ์„ ๋ฏธ์น  ๋ฟ๋งŒ ์•„๋‹ˆ๋ผ ์ง๋ฌด๋งŒ์กฑ๋„๋ฅผ ๋งค๊ฐœ๋ฅผ ํ†ตํ•ด ๊ฐ„์ ‘์ ์œผ๋กœ ๋ฏธ์น˜๋Š” ์˜ํ–ฅ๋„ ์ƒ๋‹นํ•˜๋‹ค๋Š” ์ ์„ ๋ฐํž˜์œผ๋กœ์จ ๊ณต๊ธฐ์—… ์ข…์‚ฌ์ž๋“ค์˜ ์ง๋ฌด๋งŒ์กฑ๋„ ์ œ๊ณ ๋ฅผ ํ†ตํ•œ ์ธ์ ์ž์›๊ด€๋ฆฌ๊ฐ€ ์ด๋ฃจ์–ด์ ธ์•ผ ํ•œ๋‹ค๋Š” ํฐ ๋ฐฉํ–ฅ์„ ์ œ์‹œํ•˜์˜€๋‹ค. ๋˜ํ•œ ๊ฐ๊ฐ์˜ ์ธ์ ์ž์›๊ด€๋ฆฌ ๊ธฐ๋ฒ•๋ณ„๋กœ ๊ณต๊ธฐ์—… ์ข…์‚ฌ์ž์˜ ์กฐ์ง๋ชฐ์ž… ๋ฐ ์ง๋ฌด๋งŒ์กฑ์˜ ๋งค๊ฐœ๋ฅผ ํ†ตํ•ด ์กฐ์ง๋ชฐ์ž…์— ๋ฏธ์น˜๋Š” ์˜ํ–ฅ์ด ์–ด๋–ป๊ฒŒ ๋‹ค๋ฅธ์ง€ ํ™•์ธํ•˜๊ณ , ์ด๋Ÿฌํ•œ ํšจ๊ณผ๊ฐ€ ์„ฑ๋ณ„์— ๋”ฐ๋ผ ์–ด๋–ป๊ฒŒ ๋‹ฌ๋ผ์ง€๋Š”์ง€ ์กฐ์ ˆ๋œ ๋งค๊ฐœํšจ๊ณผ๋ฅผ ๊ฒ€์ฆํ•จ์œผ๋กœ์จ ๋‹ค์Œ๊ณผ ๊ฐ™์ด ๊ตฌ์ฒด์ ์ธ ์‹ค๋ฌด์  ์‹œ์‚ฌ์ ์„ ์–ป์„ ์ˆ˜ ์žˆ์—ˆ๋‹ค. ์ฒซ์งธ, ์—ฐ๊ตฌ๊ฒฐ๊ณผ์— ๋‚˜ํƒ€๋‚ฌ๋“ฏ์ด ์ „์ฒด์ ์œผ๋กœ ๋ณผ ๋•Œ ์ธ์ ์ž์›๊ด€๋ฆฌ๊ฐ€ ์ง๋ฌด๋งŒ์กฑ๊ณผ ์กฐ์ง๋ชฐ์ž…์— ์ •(+)์˜ ์˜ํ–ฅ์„ ์ฃผ๋Š” ๊ฒƒ์œผ๋กœ ๋‚˜ํƒ€๋‚œ ์ ์€ ๊ณต๊ธฐ์—…์˜ ๊ฒฝ์˜ ์ „๋žต์  ์ฐจ์›์—์„œ๋„ ์ธ์ ์ž์›๊ด€๋ฆฌ ์ œ๋„๋ฅผ ํ™œ์šฉํ•  ์œ ์ธ์ด ์ถฉ๋ถ„ํ•˜๋‹ค๊ณ  ๋ณผ ์ˆ˜ ์žˆ๋‹ค. ๋‘˜์งธ, ์ธ์ ์ž์›๊ด€๋ฆฌ๊ฐ€ ์ง๋ฌด๋งŒ์กฑ์„ ๋งค๊ฐœํ•˜์—ฌ ์กฐ์ง๋ชฐ์ž…์œผ๋กœ ์ด์–ด์ง€๋Š” ๊ด€๊ณ„์˜ ๊ฐ•๋„๊ฐ€ ๊ฐ๊ฐ์˜ ์ธ์ ์ž์›๊ด€๋ฆฌ ๊ธฐ๋ฒ•์— ๋”ฐ๋ผ ๋‹ฌ๋ผ์ง„๋‹ค๋Š” ์ ์—์„œ๋„ ์˜๋ฏธํ•˜๋Š” ๋ฐ”๊ฐ€ ํฌ๋‹ค. ๊ต์œกํ›ˆ๋ จ์ œ๋„์™€ ์ธ์‚ฌํ‰๊ฐ€ ์ œ๋„ ํ•ญ๋ชฉ์ด ๋‹ค๋ฅธ ์š”์†Œ๋“ค์— ๋น„ํ•ด ์ง๋ฌด๋งŒ์กฑ์ด๋‚˜ ์กฐ์ง๋ชฐ์ž…์— ๋” ๋งŽ์€ ์˜ํ–ฅ์„ ์ฃผ๋Š” ๊ฒƒ์œผ๋กœ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ์ด๋Š” ๊ณต๊ธฐ์—…์—์„œ ์‹œํ–‰ํ•˜๊ณ  ์žˆ๋Š” ์ธ์ ์ž์›๊ด€๋ฆฌ ๊ฐ€์šด๋ฐ ๋‘ ๊ฐ€์ง€ ์š”์†Œ๊ฐ€ ํƒ€ ์š”์†Œ์— ๋น„ํ•ด ์ข…์—…์›๋“ค์˜ ์ง๋ฌด๋งŒ์กฑ๋„๋ฅผ ๋†’์ด๊ณ  ์กฐ์ง๋ชฐ์ž…๋„๋ฅผ ํ–ฅ์ƒ์‹œํ‚ค๋Š”๋ฐ ์œ ํšจํ•จ์„ ์ž…์ฆํ•œ ๊ฒƒ์ด๋ผ ํ•˜๊ฒ ๋‹ค. ์…‹์งธ, ์ธ์ ์ž์›๊ด€๋ฆฌํ™œ๋™ ์ค‘ ์„ฑ๊ณผ๋ณด์ƒ ํ•ญ๋ชฉ์ด ์ง์ ‘์ ์œผ๋กœ ์กฐ์ง ๋ชฐ์ž…์— ๋Œ€ํ•ด ๋งŒ์กฑํ•  ๋งŒํ•œ ์˜ํ–ฅ์„ ์ฃผ์ง€ ๋ชปํ•œ ๊ฒƒ์œผ๋กœ ๋‚˜ํƒ€๋‚ฌ๋‹ค. ์ด๋Š” ์„ฑ๊ณผ๋ณด์ƒ์— ๋Œ€ํ•œ ๊ฒฌํ•ด ์ฐจ์ด๋‚˜ ๋ถˆ๋งŒ์ด ์ž ์žฌ๋˜์–ด ์žˆ์Œ์„ ์‹œ์‚ฌํ•˜๋Š” ๊ฒƒ์œผ๋กœ ํŒ๋‹จ๋œ๋‹ค. ๋„ท์งธ, ๋ณด์ง๊ด€๋ฆฌ๊ฐ€ ์ง๋ฌด๋งŒ์กฑ๋„๋ฅผ ๋งค๊ฐœํ•˜์—ฌ ์กฐ์ง๋ชฐ์ž…๋„์— ๋ฏธ์น˜๋Š” ์˜ํ–ฅ์ด ๋‚จ์„ฑ๋ณด๋‹ค ์—ฌ์„ฑ์—๊ฒŒ ํฌ๋‹ค๋Š” ๊ฒƒ์„ ์•Œ ์ˆ˜ ์žˆ๋‹ค. ์ด๋ฅผ ํ†ตํ•ด ๊ณต๊ธฐ์—…์˜ ์—ฌ์„ฑ ์ข…์‚ฌ์ž๋“ค์˜ ์ง๋ฌด๋งŒ์กฑ๋„์™€ ์กฐ์ง๋ชฐ์ž…๋„๋ฅผ ๋†’์ผ ์ˆ˜ ์žˆ๋Š” ๊ท ํ˜•์ ์ธ ๋ณด์ง๋ฐฐ์น˜ ๋ชจ๋ธ ๊ตฌ์ถ•์ด ํ•„์š”ํ•˜๋‹ค๋Š” ์ ์„ ์•Œ ์ˆ˜ ์žˆ๊ณ  ๊ณต๊ธฐ์—…์˜ ์—ฌ์„ฑ ์ข…์‚ฌ๋“ค์˜ ๋ณด์ง๊ด€๋ฆฌ์— ๋Œ€ํ•œ ๊ด€๋ฆฌ๋ฅผ ๊ฐ•ํ™”ํ•œ๋‹ค๋ฉด ์ด๋Š” ์—ฌ์„ฑ ์ข…์‚ฌ์ž๋“ค์˜ ์ง๋ฌด ๋งŒ์กฑ๋„๋ฅผ ๋†’๊ฒŒ ํ•ด์ฃผ๋ฉด ์กฐ์ง๋ชฐ์ž…๋„๋ฅผ ๊ฐ•ํ™”ํ•˜๋Š” ํšจ๊ณผ๊ฐ€ ํด ๊ฒƒ์ด๋‹ค. ๋‹ค๋งŒ, ๋ณธ ์—ฐ๊ตฌ์˜ ๊ฒฐ๊ณผ๋ฅผ ํ•ด์„ํ•จ์— ์žˆ์–ด์„œ ๋‹ค์Œ๊ณผ ๊ฐ™์€ ํ•œ๊ณ„์— ์œ ๋…ํ•  ํ•„์š”๊ฐ€ ์žˆ๋‹ค. ๋ณธ ์—ฐ๊ตฌ๋Š” K๊ณต์‚ฌ์—์„œ ์‹ค์‹œํ•˜๋Š” ์„ค๋ฌธ์กฐ์‚ฌ ๊ฒฐ๊ณผ๋ฅผ ํ™œ์šฉํ•˜์—ฌ ์ง„ํ–‰ํ•˜์˜€์ง€๋งŒ ๋ณ€์ˆ˜๋ณ„๋กœ ์ธก์ •๋ฌธํ•ญ์ด ๋‹จ์ˆœํ•˜๊ฒŒ ์„ค๊ณ„๋˜์–ด ์žˆ์–ด ์„ธ๋ฐ€ํ•œ ์ธก์ •์ด ์ง„ํ–‰๋˜์ง€ ๋ชปํ•˜์˜€๋‹ค. ํ–ฅํ›„ ์—ฐ๊ตฌ์—์„œ๋Š” ๋ณด๋‹ค ์„ธ๋ฐ€ํ•œ ์ธก์ •์„ ์œ„ํ•ด ๊ฐ ๋ณ€์ˆ˜๋ณ„๋กœ ์„ธ๋ฐ€ํ•œ ์„ค๋ฌธ ๊ตฌ์„ฑ์„ ํ†ตํ•ด ์ฒ™๋„ ๊ฐœ๋ฐœ์„ ํ•  ์ˆ˜ ์žˆ์„ ๊ฒƒ์ด๋‹ค. ๋˜ํ•œ ์ธ์ ์ž์›๊ด€๋ฆฌ์— ๋Œ€ํ•œ ์„ค๋ฌธ์กฐ์‚ฌ๊ฐ€ K๊ณต์‚ฌ์—์„œ ์ •๊ธฐ์ ์œผ๋กœ ์‹ค์‹œํ•˜๋Š” ์„ค๋ฌธ์ž๋ฃŒ๋กœ ์ด๋Š” ์ง์›๋“ค์ด ๋‹ต๋ณ€์‹œ ํ†ต์ƒ ๋†’์€ ์ ์ˆ˜๋ฅผ ๋ถ€์—ฌํ•  ๊ฐœ์—ฐ์„ฑ์ด ์žˆ๋‹ค. ๋”๋ถˆ์–ด ์ธ์ ์ž์›๊ด€๋ฆฌ์™€ ์ง๋ฌด๋งŒ์กฑ๋„, ์กฐ์ง๋ชฐ์ž… ๊ฐ„ ์—ฐ๊ณ„๋ฅผ ์‚ดํŽด๋ณด๊ธฐ ์œ„ํ•ด์„œ๋Š” ์ข…๋‹จ์  ์—ฐ๊ตฌ๊ฐ€ ์ถ”๊ฐ€๋œ๋‹ค๋ฉด ๋” ์œ ์šฉํ•˜๊ฒ ์ง€๋งŒ ๋ณธ ์—ฐ๊ตฌ์—์„œ๋Š” ํšก๋‹จ์ ์ธ ์—ฐ๊ตฌ๋ฐฉ๋ฒ•์„ ์‹ค์‹œํ•˜์˜€๊ธฐ ๋•Œ๋ฌธ์— ์‹œ๊ฐ„์˜ ํ๋ฆ„์— ๋”ฐ๋ฅธ ๋ณ€ํ™”๋ฅผ ๋ฐ˜์˜ํ•˜์ง€ ๋ชปํ•˜์˜€๋‹ค. ๋˜ํ•œ ํŠน์ • ์‹œ์ ์— ๊ด€์ธก๋œ ํšก๋‹จ์ž๋ฃŒ๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ ๋ถ„์„์ด ์ด๋ฃจ์–ด์กŒ๋‹ค๋Š” ์ ์—์„œ ์ž ์žฌ์  ๋‚ด์ƒ์„ฑ์˜ ๋ฌธ์ œ๋ฅผ ์ ์ ˆํžˆ ํ†ต์ œํ•˜์ง€ ๋ชปํ•˜์˜€๋‹ค๋Š” ํ•œ๊ณ„๊ฐ€ ์žˆ๋‹ค. ๋”ฐ๋ผ์„œ ์ถ”ํ›„ ์—ฐ๊ตฌ์—์„œ๋Š” ์ ์ ˆํ•œ ๋„๊ตฌ๋ณ€์ˆ˜๋ฅผ ๋ฐœ๊ตดํ•˜๊ฑฐ๋‚˜ ํŒจ๋„์ž๋ฃŒ๋ฅผ ์‚ฌ์šฉํ•˜์—ฌ ๋ถ„์„์„ ์ง„ํ–‰ํ•˜์—ฌ ์ž ์žฌ์  ๋‚ด์ƒ์„ฑ์˜ ๋ฌธ์ œ๋ฅผ ์™„ํ™”์‹œํ‚ฌ ํ•„์š”๊ฐ€ ์žˆ๋‹ค.์ œ 1 ์žฅ ์„œ ๋ก  1 ์ œ 1 ์ ˆ ์—ฐ๊ตฌ์˜ ํ•„์š”์„ฑ ๋ฐ ๋ชฉ์ 1 1. ์—ฐ๊ตฌ์˜ ๋ฐฐ๊ฒฝ 1 2. ์—ฐ๊ตฌ์˜ ๋ชฉ์  3 ์ œ 2 ์ ˆ ์—ฐ๊ตฌ๋Œ€์ƒ๊ณผ ์—ฐ๊ตฌ๋ฐฉ๋ฒ• 7 1. ์—ฐ๊ตฌ๋Œ€์ƒ ๋ฐ ๋ฒ”์œ„ 7 2. ์—ฐ๊ตฌ์˜ ๋ฐฉ๋ฒ• 8 ์ œ 2 ์žฅ ์ด๋ก ์  ๋…ผ์˜์™€ ์„ ํ–‰์—ฐ๊ตฌ ๊ฒ€ํ†  9 ์ œ 1 ์ ˆ ์ธ์ ์ž์›๊ด€๋ฆฌ 9 1. ์ธ์ ์ž์›๊ด€๋ฆฌ ๊ฐœ๋… 9 2. ์ธ์ ์ž์›๊ด€๋ฆฌ์˜ ๊ตฌ์„ฑ์š”์†Œ 11 3. ์ธ์ ์ž์›๊ด€๋ฆฌ์˜ ์ค‘์š”์„ฑ 12 ์ œ 2 ์ ˆ ์กฐ์ง๋ชฐ์ž… 15 1. ์กฐ์ง๋ชฐ์ž… ๊ฐœ๋… 16 2. ์กฐ์ง๋ชฐ์ž…์˜ ์ค‘์š”์„ฑ 18 ์ œ 3 ์ ˆ ์ง๋ฌด๋งŒ์กฑ 19 1. ์ง๋ฌด๋งŒ์กฑ ๊ฐœ๋… 19 2. ์ง๋ฌด๋งŒ์กฑ์˜ ์ค‘์š”์„ฑ22 ์ œ 4 ์ ˆ ์„ ํ–‰์—ฐ๊ตฌ ๊ฒ€ํ†  ๋ฐ ๊ฐ€์„ค์„ค์ • 23 1. ์ธ์ ์ž์›๊ด€๋ฆฌ์™€ ์ง๋ฌด๋งŒ์กฑ 23 2. ์ธ์ ์ž์›๊ด€๋ฆฌ์™€ ์กฐ์ง๋ชฐ์ž… 25 3. ์ง๋ฌด๋งŒ์กฑ๊ณผ ์กฐ์ง๋ชฐ์ž… 27 4. ์ธ์ ์ž์›๊ด€๋ฆฌ์™€ ์กฐ์ง๋ชฐ์ž…๊ฐ„์˜ ์ง๋ฌด๋งŒ์กฑ์˜ ๋งค๊ฐœํšจ๊ณผ 30 5. ์„ฑ๋ณ„์ฐจ์ด : ์กฐ์ ˆ๋œ ๋งค๊ฐœํšจ๊ณผ 31 ์ œ 5 ์ ˆ K๊ณต์‚ฌ์˜ ์ธ์ ์ž์›๊ด€๋ฆฌ 32 1. ๊ต์œกํ›ˆ๋ จ32 2. ์ธ์‚ฌํ‰๊ฐ€34 3. ๋ณด์ง๊ด€๋ฆฌ 36 4. ์Šน์ง„์ œ๋„ 37 5. ์„ฑ๊ณผ๋ณด์ƒ 38 ์ œ 3 ์žฅ ์—ฐ๊ตฌ ์„ค๊ณ„ 39 ์ œ 1 ์ ˆ ์—ฐ๊ตฌ ๋ชจํ˜• 39 ์ œ 2 ์ ˆ ๋ณ€์ˆ˜์˜ ์ •์˜ ๋ฐ ์ธก์ •๋„๊ตฌ 40 1. ๋…๋ฆฝ๋ณ€์ˆ˜ 40 2. ์ข…์†๋ณ€์ˆ˜ 41 3. ๋งค๊ฐœ๋ณ€์ˆ˜ 41 4. ์กฐ์ ˆ๋ณ€์ˆ˜ 41 4. ํ†ต์ œ๋ณ€์ˆ˜ 42 ์ œ 3 ์ ˆ ์ž๋ฃŒ ์ˆ˜์ง‘ ๋ฐ ๋ถ„์„๋ฐฉ๋ฒ• 42 ์ œ 4 ์žฅ ์—ฐ๊ตฌ๊ฒฐ๊ณผ 43 ์ œ 1 ์ ˆ ์—ฐ๊ตฌ๋Œ€์ƒ์˜ ํŠน์„ฑ 43 ์ œ 2 ์ ˆ ๊ธฐ์ˆ ํ†ต๊ณ„ 45 ์ œ 3 ์ ˆ ์ƒ๊ด€๊ด€๊ณ„ 46 ์ œ 4 ์ ˆ ์—ฐ๊ตฌ๋Œ€์ƒ์˜ ์ผ๋ฐ˜์  ํŠน์„ฑ์— ๋”ฐ๋ฅธ ์ฐจ์ด 47 1. ์—ฐ๋ น 47 2. ์„ฑ๋ณ„ 49 3. ์†Œ์† 50 4. ์ง๊ตฐ 52 5. ์ง๊ธ‰ 54 ์ œ 5 ์ ˆ ์ธ์ ์ž์›๊ด€๋ฆฌ,์ง๋ฌด๋ชฐ์ž…, ์ง๋ฌด๋งŒ์กฑ ๊ฐ„ ์˜ํ–ฅ๊ด€๊ณ„ 56 1. ์ธ์ ์ž์›๊ด€๋ฆฌ์— ๋Œ€ํ•œ ์ธ์‹์ด ์ง๋ฌด๋งŒ์กฑ๋„์— ๋ฏธ์น˜๋Š” ์˜ํ–ฅ 56 2. ์ธ์ ์ž์›๊ด€๋ฆฌ์™€ ์ง๋ฌด๋งŒ์กฑ๋„๊ฐ€ ์กฐ์ง๋ชฐ์ž…๋„์— ๋ฏธ์น˜๋Š” ์˜ํ–ฅ 57 3. ์ง๋ฌด๋งŒ์กฑ์˜ ๋งค๊ฐœํšจ๊ณผ 59 4. ์„ฑ๋ณ„์˜ ์กฐ์ ˆํšจ๊ณผ ๋ฐ ์กฐ์ ˆ๋œ ๋งค๊ฐœํšจ๊ณผ 61 ์ œ 5์žฅ ๊ฒฐ๋ก  65 ์ œ 1 ์ ˆ ์—ฐ๊ตฌ๊ฒฐ๊ณผ ์š”์•ฝ ๋ฐ ์‹œ์‚ฌ์  65 1. ์—ฐ๊ตฌ๊ฒฐ๊ณผ ์š”์•ฝ 67 2. ์—ฐ๊ตฌ์˜ ์˜์˜ ๋ฐ ์‹œ์‚ฌ์  67 ์ œ 2 ์ ˆ ์—ฐ๊ตฌ์˜ ํ•œ๊ณ„ ๋ฐ ํ–ฅํ›„ ์—ฐ๊ตฌ๊ณผ์ œ 70 ์ฐธ๊ณ ๋ฌธํ—Œ 73์„

    Characterization of microtubule-binding and dimerizatino activity of Giardia lamblia end-binding 1 protein

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    End-binding 1 (EB1) proteins are evolutionarily conserved components of microtubule (MT) plus-end tracking protein that regulate MT dynamics. Giardia lamblia, with two nuclei and cytoskeletal structures, requires accurate MT distribution for division. In this study, we show that a single EB1 homolog gene of G. lamblia regulates MT dynamics in mitosis. The haemagglutinin-tagged G. lamblia EB1 (GlEB1) localizes to the nuclear envelopes and median bodies, and is transiently present in mitotic spindles of dividing cells. Knockdown of GlEB1 expression using the morpholinos-based anti-EB1 oligonucleotides, resulted in a significant defect in mitosis of Giardia trophozoites. The MT-binding assays using recombinant GlEB1 (rGlEB1) proteins demonstrated that rGlEB1102-238, but not rGlEB11-184, maintains an MT-binding ability comparable with that of the full length protein, rGlEB11-238. Size exclusion chromatography showed that rGlEB1 is present as a dimer formed by its C-terminal domain and a disulfide bond. In vitro-mutagenesis of GlEB1 indicated that an intermolecular disulfide bond is made between cysteine #13 of the two monomers. Complementation assay using the BIM1 knockout mutant yeast, the yeast homolog of mammalian EB1, indicated that expression of the C13S mutant GlEB1 protein cannot rescue the mitotic defect of the BIM1 mutant yeast. These results suggest that dimerization of GlEB1 via the 13th cysteine residues plays a role during mitosis in Giardia.ope

    Roleย ofย gamma-giardinย inย ventralย discย formationย ofย Giardiaย lamblia

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    BACKGROUND: Giardia lamblia, a protozoan pathogen causing diarrheal outbreaks, has characteristic cytoskeletal structures including eight flagella, a median body and a ventral disc. Gamma-giardin is a unique component protein of the cytoskeleton of this protozoan. RESULTS: Through comparative proteomic analysis between different stages of the cell cycle, G. lamblia ฮณ-giardin (Glฮณ-giardin) was identified as an upregulated protein in the G2-phase. Increased Glฮณ-giardin expression in G2 was confirmed by western blot and real-time polymerase chain reaction analyses. Knockdown of this protein using a morpholino affected the formation of ventral discs, especially the microribbons of the discs, but exerted little effect on the binding ability of G. lamblia. The number of cells with four nuclei was increased in Glฮณ-giardin-knockdown cells. Expression of Glฮณ-giardin was decreased during encystation, in contrast with the G2-phase. CONCLUSIONS: Knockdown experiments demonstrated that Glฮณ-giardin is a component of the trilaminar structure of the ventral disc. Expression of Glฮณ-giardin is induced in the G2-phase prior to active cell division, whereas its expression decreases during encystation, a dormant stage of G. lamblia.ope

    Kinesin-13, a Motor Protein, is Regulated by Polo-like Kinase in Giardia lamblia

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    Kinesin-13 (Kin-13), a depolymerizer of microtubule (MT), has been known to affect the length of Giardia. Giardia Kin-13 (GlKin-13) was localized to axoneme, flagellar tips, and centrosomes, where phosphorylated forms of Giardia polo-like kinase (GlPLK) were distributed. We observed the interaction between GlKin-13 and GlPLK via co-immunoprecipitation using transgenic Giardia cells expressing Myc-tagged GlKin-13, hemagglutinin-tagged GlPLK, and in vitro-synthesized GlKin-13 and GlPLK proteins. In vitro-synthesized GlPLK was demonstrated to auto-phosphorylate and phosphorylate GlKin-13 upon incubation with [ฮณ-32P]ATP. Morpholino-mediated depletion of both GlKin-13 and GlPLK caused an extension of flagella and a decreased volume of median bodies in Giardia trophozoites. Our results suggest that GlPLK plays a pertinent role in formation of flagella and median bodies by modulating MT depolymerizing activity of GlKin-13.ope

    Trichomonas vaginalis ฮฑ-Actinin 2 Modulates Host Immune Responses by Inducing Tolerogenic Dendritic Cells via IL-10 Production from Regulatory T Cells

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    Trichomonas vaginalis is a pathogen that triggers severe immune responses in hosts. T. vaginalis ฮฑ-actinin 2, Tvฮฑ-actinin 2, has been used to diagnose trichomoniasis. This study was undertaken to examine the role of Tvฮฑ-actinin 2 as an antigenic molecule to induce immune responses from humans. Western blot analysis using anti-Tvฮฑ-actinin 2 antibodies indicated its presence in the secreted proteins of T. vaginalis. ELISA was employed to measure cytokine production by vaginal epithelial cells, prostate cells, mouse dendritic cells (DCs), or T cells stimulated with T. vaginalis or Tvฮฑ-actinin 2 protein. Both T. vaginalis and rTvฮฑ-actinin 2 induced cytokine production from epithelial cell lines, including IL-10. Moreover, CD4+CD25- regulatory T cells (Treg cells) incubated with rTvฮฑ-actinin 2-treated DCs produced high levels of IL-10. These data indicate that Tvฮฑ-actinin 2 modulates immune responses via IL-10 production by Treg cells.ope

    A Standard Public Order Treaty Carve-out as a Means for Balancing Regulatory Interests in International Investment Agreements

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    ํ•™์œ„๋…ผ๋ฌธ (๋ฐ•์‚ฌ)-- ์„œ์šธ๋Œ€ํ•™๊ต ๋Œ€ํ•™์› : ๋ฒ•ํ•™๊ณผ, 2017. 2. ์‹ ํฌํƒ.Since the start of the BIT program, the purpose of BITs was predominantly motivated by the sole objective of providing foreign investment protection mostly for the benefit of the capital-exporting, developed countries. The capital-importing, developing countries entered into BITs to attract foreign investment without a comprehensive awareness of the legal ramifications of BITs. However, the conclusion of FTAs with investment chapters such as the NAFTA expanded the narrowly conceived BIT goal of investment protection to include other purposes like investment promotion and liberalization. Prior to the NAFTA, carving out policy space in international investment agreements (IIAs) was not a real concern until the NAFTA experience demonstrated that investor-State arbitrations could be initiated not only against the developing States, but also against the developed States. Moreover, the ICSID cases against Argentina have been instrumental in bringing attention to the need of host States to exercise regulatory power. These experiences helped to create an understanding for both the developed and developing States that a significant legal consequence of concluding IIAs is that their sovereign right to regulate various aspects of public interest might result in a breach of the IIA. The objective of this research is to fill a meaningful gap in international investment law to enable States to better exercise their sovereign right to regulate by using the public order clause in the non-precluded measures provision of the U.S.-Argentina BIT as a starting point. The questions asked in this study include whether a public order carve-out for public interest matters is emerging and, if so, whether the public order carve-out can equip host States with the flexibility needed to exercise their regulatory authority. This research makes the discovery that the concept of public order is undefined in international investment law making it difficult for investment tribunals to interpret the public order carve-out in a consistent and predictable manner. On one level, the notion of the right to regulate is being incorporated in the most current versions of IIAs without an appreciation of how it should apply in international investment law despite the lessons exemplified in the ICSID arbitrations against Argentina. On another level, BITs have been designed to usually only contain substantive obligations. Although the recent trend of IIAs is to include some variation of a general exceptions provision to limit the scope of the substantive obligations, the practice remains largely inconsistent and borrowed from the WTO/GATS jurisprudence. However, this research concludes that the inclusion of a standard public order carve-out specifically aimed at preserving the regulatory space of States should become a fixed feature of future investment treaties to better address the growing aggregate community interests of IIA stakeholders. This ultimately requires that the base values and concerns of the participants in international investment law be evaluated.1. Introduction 1 1.1. Trends of International Investment Agreements 1 1.1.A. Changes in BIT/IIA Perspective 1 1.1.B. Aggregate Community Interests of the IIA Stakeholders 16 1.2. Problem Identification 54 2. Preserving Regulatory Space through the Public Order Carve-out Provision in IIAs 62 2.1. The Multiple Meanings of "Public Order" 67 2.1.A. The National Law Concept of Public Order 65 2.1.B. The International Law Concept of Public Order 72 2.2. The State Concept of Public Order in the Context of International Organizations 78 2.2.A. Public Order in the European Union 78 2.2.B. Public Order in the WTO/GATS 86 2.2.C. Public Order in Human Rights Conventions 92 2.3. The Customary International Law Source of the Public Order Concept 105 2.4. Concluding Remarks 117 3. States' Treatment of the Public Order Carve-out in IIAs 121 3.1. Textual Transformation of the Public Order Carve-out in IIAs 121 3.1.A. Prior to the 1980s: Public Order Provisions in FCNs 121 3.1.B. Prior to the 2000s: Public Order Provisions in BITs 125 3.1.C. Current Trends: FTA Investment Chapters with Regulatory Space Carve-outs 131 3.2. Other Methods of Preserving Regulatory Space in IIAs 154 3.2.A. Legitimate Public Welfare Objectives 154 3.2.B. Reservations 164 3.2.C. National Security 170 3.2.D. Essential Security Interest 184 3.3. Concluding Remarks 190 4. Treatment of the Public Order Carve-out by the ICSID Tribunals in Cases Arising out of the U.S.-Argentina BIT 192 4.1. Fact Pattern of the Argentine ICSID Cases 192 4.2. The Argentine ICSID Tribunals' Standard of Review for the Public Order Carve-out 200 4.2.A. ILC Article 25 as Applied to the Public Order Carve-out 200 4.2.B. The Argentine ICSID Tribunals' Treatment of the NPM Treaty Provision 217 4.3. Concluding Remarks 237 5. A Standard Public Order Carve-out in IIAs to Balance Stakeholders' Interests 241 5.1. Proposal of a Sample Standard Public Order Carve-out 241 5.1.A. Evolving Object and Purpose of IIAs 243 5.1.B. Scope of a Standard Public Order Carve-out 251 5.1.C. Distinguishing the Standard Public Order Carve-out from the WTO/GATS-inspired General Exceptions Clause 257 5.1.D. The Public Order Carve-out is not a Lex Specialis Rule 271 5.1.E. Preserving Regulatory Space in the Absence of the Public Order Carve-out 281 5.2. The Legitimate Policy Objectives in the Proposed Standard Public Order Carve-out as Explained by Existing Cases 293 5.3. Concluding Remarks 299 6. Conclusion 301 ์ฐธ๊ณ ๋ฌธํ—Œ 308 ๊ตญ๋ฌธ์ดˆ๋ก 346Docto

    Role of ฮฑ-Actinin 2 in Cytoadherence and Cytotoxicity of Trichomonas vaginalis

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    Trichomonas vaginalis is a pathogen that triggers severe immune responses in hosts. T. vaginalis ฮฑ-actinin 2 (Tvฮฑ-actinin 2) has been used to diagnose trichomoniasis. Tvฮฑ-actinin 2 was dissected into three parts; the N-terminal, central, and C-terminal portions of the protein (#1, #2, and #3, respectively). Western blot of these Tvฮฑ-actinin 2 proteins with pooled patients' sera indicated that #2 and #3, but not #1, reacted with those sera. Immunofluorescence assays of two different forms of T. vaginalis (trophozoites and amoeboid forms), using anti-Tvฮฑ-actinin 2 antibodies, showed localization of Tvฮฑ-actinin 2 close to the plasma membranes of the amoeboid form. Fractionation experiments indicated the presence of Tvฮฑ-actinin 2 in cytoplasmic, membrane, and secreted proteins of T. vaginalis. Binding of fluorescence-labeled Trichomonas to vaginal epithelial cells and prostate cells was decreased in the antibody blocking experiment using anti-Tvฮฑ-actinin 2 antibodies. Pretreatment of T. vaginalis with anti-rTvฮฑ-actinin 2 antibodies also resulted in reduction in its cytotoxicity. Flow cytometry, ligand-binding immunoblotting assay, and observation by fluorescence microscopy were used to detect the binding of recombinant Tvฮฑ-actinin 2 to human epithelial cell lines. Specifically, the truncated N-terminal portion of Tvฮฑ-actinin 2, Tvฮฑ-actinin 2 #1, was shown to bind directly to vaginal epithelial cells. These data suggest that ฮฑ-actinin 2 is one of the virulence factors responsible for the pathogenesis of T. vaginalis by serving as an adhesin to the host cells.ope

    Functional Identification of a Nuclear Localization Signal of MYB2 Protein in Giardia lamblia

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    MYB2 protein was identified as a transcription factor that showed encystation-induced expression in Giardia lamblia. Although nuclear import is essential for the functioning of a transcription factor, an evident nuclear localization signal (NLS) of G. lamblia MYB2 (GlMYB2) has not been defined. Based on putative GlMYB2 NLSs predicted by 2 programs, a series of plasmids expressing hemagglutinin (HA)-tagged GlMYB2 from the promoter of G. lamblia glutamate dehydrogenase were constructed and transfected into Giardia trophozoites. Immunofluorescence assays using anti-HA antibodies indicated that GlMYB2 amino acid sequence #507-#530 was required for the nuclear localization of GlMYB2, and this sequence was named as NLSGlMYB2. We further verified this finding by demonstrating the nuclear location of a protein obtained by the fusion of NLSGlMYB2 and G. lamblia glyceraldehyde 3-phosphate dehydrogenase, a non-nuclear protein. Our data on GlMYB2 will expand our understanding on NLSs functioning in G. lamblia.ope

    RNA-sequencingย Profilesย ofย Cellย Cycle-Relatedย Genesย Upregulatedย during theย G2-Phaseย inย Giardiaย lamblia

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    To identify the component(s) involved inย cellย cycle control in the protozoanย Giardiaย lamblia, cells arrested at the G1/S- orย G2-phaseย by treatment with nocodazole and aphidicolin were prepared from the synchronizedย cellย cultures.ย RNA-sequencingย analysis of the 2 stages ofย Giardiaย cellย cycle identified severalย cellย cycleย genesย that were up-regulated at theย G2-phase. Transcriptome analysis of cells in 2 distinctย cellcycle stages of G.ย lambliaย confirmed previously reported components ofย cellย cycle (PcnA, cyclin B, and CDK) and identified additionalย cellcycle components (NEKs, Mad2, spindle pole protein, and CDC14A). This result indicates that theย cellย cycle machinery operates in this protozoan, one of the earliest diverging eukaryotic lineages.ope
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