Alternative splicing and nonsense-mediated decay of circadian clock genes under environmental stress conditions in Arabidopsis

학위논문 (석사)-- 서울대학교 대학원 : 화학부, 2014. 8. 박충모.The circadian clock enables living organisms to anticipate recurring daily and seasonal fluctuations in their growth habitats and synchronize their biology to the environmental cycle. The plant circadian clock consists of multiple transcription-translation feedback loops that are entrained by environmental signals, such as light and temperature. In recent years, alternative splicing emerges as an important molecular mechanism that modulates the clock function in plants. Several clock genes are known to undergo alternative splicing in response to changes in environmental conditions, suggesting that the clock function is intimately associated with environmental responses via the alternative splicing of the clock genes. However, the alternative splicing events of the clock genes have not been studied at the molecular level. Here, we systematically examined whether major clock genes undergo alternative splicing under various environmental conditions in Arabidopsis. We also investigated the fates of the RNA splice variants of the clock genes. It was found that the clock genes, including EARLY FLOWERING 3 (ELF3) and ZEITLUPE (ZTL) that have not been studied in terms of alternative splicing, undergo extensive alternative splicing through diverse modes of splicing events, such as intron retention, exon skipping, and selection of alternative 5 splice site. Their alternative splicing patterns were differentially influenced by changes in photoperiod, temperature extremes, and salt stress. Notably, the RNA splice variants of TIMING OF CAB EXPRESSION 1 (TOC1) and ELF3 were degraded through the nonsense-mediated decay (NMD) pathway, whereas those of other clock genes were insensitive to NMD. Taken together, our observations demonstrate that the major clock genes examined undergo extensive alternative splicing under various environmental conditions, suggesting that alternative splicing is a molecular scheme that underlies the linkage between the clock and environmental stress adaptation in plants. It is also envisioned that alternative splicing of the clock genes plays more complex roles than previously expected.CONTENTS ABSTRACT..............................................................................................................1 CONTENTS..............................................................................................................3 INTRODUCTION.....................................................................................................5 RESULTS Major clock genes undergo extensive alternative splicing.........................8 The modes of splicing events are diverse in the clock genes................13 Some RNA splice variants of the clock genes are degraded by NMD................................................................................................................18 Protein isoforms of the clock components are defective in different functional domains.........................................................................................23 Short days suppress the alternative splicing of TOC1 and ELF3 genes................................................................................................................26 Low temperatures suppress CCA1 and ELF3 alternative splicing but induce TOC1 alternative splicing.................................................................28 Heat induces the alternative splicing of CCA1, PRR7, TOC1, and ELF3 genes.....................................................................................................31 High salinity suppresses ELF3 alternative splicing....................................33 DISCUSSION..........................................................................................................35 MATERIALS AND METHODS Bioinformatics software.................................................................................40 Plant materials and growth conditions.........................................................40 Analysis of gene transcript levels................................................................40 Absolute quantification of gene transcripts.................................................43 Abiotic stress treatments................................................................................43 Cycloheximide (CHX) treatments.................................................................43 LITERATURE CITED...........................................................................................44Maste

Solution Against Conflict Between Teachers And Educational Administrative Staff

People experience lots of conflicts on living. They are exposed to various conflicts between individual and individual, individual and organization, organization and organization, even in themselves. Especially, some of those can mentally, psychologically impose whatever it is within organization or individual upon them if they live in community life. In the case of that these complicated matters make a role to stimuli, those can be accelerator to be an element developing organization. However, if the level of conflicts runs to excess, it may menace general operation. Moreover it has negative aside that can destroy both organization and individual. Thus, it should be important for maintenance of strong community to properly manage conflicts. No doubts, conflicts mentioned above also exist in administrative education organ including school. The objectives of this research is to contribute to make good and ideal environment of school organization to feel effective and proud looking for practical solution of conflicts and providing proper information to release them. This study helps you to observe concrete sources in school organization through actual analyzation into teachers and public servants working in administrative education organ after forming theoretical foundation of conflicts using references preceded research to inquire into the causes that effect on complicated matters between teachers and public servants working in administrative education organ and level of conflicts. This study is to observe conflicts between administrative worker and educational instructor, and suggest a plan to solve them. Therefore, it works over through question paper for more positive approach after forming theoretical foundation of conflicts using references preceded research. The questionnaires are distributed to 100 administrative workers and 200 educational instructors working in middle and high school, then collected. 280 papers are collected but 12 of them are not sufficient so that it is analyzed only 268 as t verification.목 차 Ⅰ. 서 론 ···················································1 1.문제의식 ··················································1 2.연구목적 ··················································1 3.연구내용 ··················································3 Ⅱ.이론적 배경 ··········································4 1.학교 조직의 개념과 특성 ······················4 가. 조직의 개념과 특성 ····························4 나. 학교 조직의 개념 ································5 다. 학교 조직의 특성 ································5 2.교사와 교육행정직의 역할 ···················9 가. 교사와 교육행정직의 특성 ··············· 9 나. 교사의 역할 ·········································10 다. 교육행정직의 역할 ·····························12 3.갈등의 개념과 유형 ·······························13 가. 갈등의 개념 ·········································13 나. 갈등의 기능 ········································ 14 다. 갈등의 유형 ·········································16 라. 갈등의 원인 ·········································19 마. 갈등의 해결 ·········································22 4.교사와 교육행정직간의 갈등 원인 ······26 가. 학교조직 내 갈등의 원인 ···················26 나. 교사와 교육행정직간 갈등의 원인 ···28 5.선행연구고찰 ··········································30 Ⅲ.연구방법 ················································34 1.연구 대상 및 표집 방법 ·························34 2.도구의 설계 ·············································34 3.자료 처리 ················································ 37 Ⅳ.연구 결과 및 해석 ······························· 38 Ⅴ.요약 및 결론 ·········································54 참고문헌 ·····················································59 부 록 ····················································· 6

Evaluation and Comparison of Asymptotic Variance based on Diagonal Distribution in Clayton Family

Maste