• 미생물학회지
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• 제32권1호
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• pp.12-19
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• 1994

Saccharomyces cerevisiae의 KEMI 유전자는 세포의 영양 상태에 따라 spindle pole body나 microtubules의 기능을 조절하는 것으로 알려져 있다. 이 유전자 산물의 세포내 분포 및 기능을 규명하기 위하여, KEM1::lacZ 융합 유전자를 제조하였다. 즉, 클론된 KEM1 유전자에 대장균의 ${\beta}$-galactosidase 구조유전자를 갖는 mini-Tn10-LUK element를 무작위 삽입한 pool을 제조하고, 이를 분석하여 KEM1의 기능 부위가 약 3.5kb에 해당함을 확인하였고, KEM1의 기능이 살아있는 KEM1::lacZ 융합 유전자의 클론을 선별하였다. 이 클론을 ${\beta}$-galactosidase 항체를 이용한 indirect immunofluorescence 방법으로 분석하여 KEM1::lacZ 융합 단백질이 핵주변에 위치함을 확인하였다.

• BMB Reports
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• 제32권1호
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• pp.92-97
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• 1999

Cytokinesis and septation should be coordinated to nuclear division in the cell division cycle for precise transmission of the genome into daughter cells. byr4, an essential gene in fission yeast Schizosaccharomyces pombe, regulates the timing of cytokinesis and septation in a dosage-dependent manner. We examined the intracellular localization of the Byr4 protein by expressing byr4 as a fusion of green fluorescence protein (GFP). The Byr4 protein localizes as a single dot on the nuclear periphery of interphase cells, duplicates before mitosis, and the duplicated dots segregate with the nuclei in anaphase. The behavior of Byr4p throughout the cell cycle strongly suggests that Byr4p is localized to the spindle pole body (SPB), a microtubule organizing center (MTOC) in yeast. The presence of the Byr4 protein in the SPB is consistent with its function to coordinate mitosis and cytokinesis. We also mapped the domains of Byr4p for its proper localization to SPB by expressing various byr4 deletion mutants as GFP fusions. Analyses of the diverse byr4 deletion mutants suggest that the indirect repeats and the regions homologous to the open reading frame (ORF) YJR053W of S. cerevisiae in its C-terminus are essential for its localization to the SPB.

• 한국균학회지
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• 제24권1호통권76호
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• pp.1-7
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• 1996

느타리버섯균의 이핵체 체세포 균사에서 분열전 및 분열후의 핵과 분열중의 핵을 화학고정방법과 동결교체방법을 이용하여 균사분화과정중의 성상체 미세소관의 미세구조적 동태를 조사하였다. 많은 수의 성상체 미세소관들이 이동중인 분열전의 핵들과 연관되어 있었으며, 분열전의 핵이 이동하는 시기에 SPB의 분리가 진행됨이 발전되었다. 분열전 이동중의 핵과는 대조적으로 SPB의 분리가 더 이상 일어나지 않는 분열중의 이거나 분열이 끝난 핵에서는 성상체미세소관이 덜 발달되어 있었다. 활발히 이동할 것으로 추측되는 분열후의 핵에서 핵과 연관된 성상체미세소관이 잘 발달되어 있지 않음은 특이한 점이다. 분열중의 모든 핵에서 성상체미세소관이 SPB에서 뻗어나오며 인은 핵막에 남아있다. 핵의 분열과 핵의 이동 및 SPB의 분리와 관련된 성상체미세소관의 기능에 대하여 논의하였다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1994년도 한국생물과학협회 학술발표대회
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• pp.246.2-246
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• 1994

• Journal of Plant Biology
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• 제30권4호
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• pp.225-247
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• 1987

Meiosis and postmeiotic mitosis in Boletus rubinellus were examined ultrastructurally. Meriosis occurred at the apex of the basidium. A sausage-shaped spindle pole body(SPB) was observed along with the presence of synaptonemal complexes during pachytene and a diglobular SPB was present on late pachytene or diplotene nuclei. During metaphase I, the monoglobular SPB at the spindle pole was surrounded bya membrane and the nuclear enveloope was discontinuous. At anaphase I, the chromosomes became better defined and formed a central spindle. The nucleolus was extruded from the nucleus. During anaphase I, the SPB was excluded from the chromosomal region by a membrane and both poles were fully separated to opposite sides of the basidial wall. In meiosis II, the two nuclei divided synchronously and the spindles were parallel. The spindles were smaller than in meiosis I, while the SPB was approximately the same size as that of the similar stage in meiosis I. During anaphasetelophase II, the SPB was surrounded by a cap of endoplasmic reticulum (ER) that delimited it from the spindle. The postmeiotic interphase nuclei migrated to the mid-region of the basidium before migration to the spores. The SPB at this stage was diglobular. A postmeiotic mitosis occurred within the basidiospore, and the plane of the spindle was obique to the long axis of the spore. The spindle and SPB were smaller than at meiosis I and there were fewer nonchromosomal microtubules. At anaphase, the nucleolus was present inside the nuclear envelope but lateral to the spindle.

• 미생물학회지
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• 제30권1호
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• pp.37-41
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• 1992

Saccharomjyces cerevisiae에서 KEM1 유전자는 세포분열시 microtubules과 spindle pole body 구조체의 새로운 기능에 관여하는 것으로 알려져 있다. KEM1과 유사하거나 연관이 있는 기능을 갖는 새로운 유전자들을 찾는 목적으로 kem1 돌연변이의 high copy suppressor 유전자, ROK1, 를 찾아냈다. ROK1은 high copy 플라스미드에 클로닝되었을 때 kem1을 suppression 하고, low copy 플라스미드에서는 suppression 하지 않는다. kem1 돌연변이의 benomyl에 대한 민감성과 Kar enhancing 표현서을 동시에 suppression 하는 두 개의 클론을 분리하였으며, 제한요소로 분석했을 때 9.0kb의 insert 를 지닌 동일한 클론이었다. 이 suppressor 유전자 ROK1의 제한지도를 작성하였고, 그 결과 KEM1 이 아닌 다른 유전자인 것으로 나타났다. Suncloning 실험으로 ROK1은 적어도 3.0kb의 기능부위를 갖음을 확인했다.

• 미생물학회지
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• 제52권3호
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• pp.383-387
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• 2016

분열효모 Schizosaccharomyces pombe의 cdc31 유전자는 진화적으로 잘 보존된 $Ca^{2+}$-결합 centrin/CDC31 계열에 속하며 방추극체(spindle pole body)의 한 성분인 단백질을 암호화하고 있다. 이 논문에서는 S. pombe의 Cdc31 단백질이 방추극체뿐만 아니라 TREX-2 복합체의 구성인자로서 mRNA의 핵에서 세포질로의 방출에 영향을 미치는지 알아보았다. cdc31 유전자의 발현을 억제하면 생장 결함을 보였고, $poly(A)^+$ RNA도 핵 안에 축적되는 현상을 보였다. 한편 cdc31 유전자를 과발현시키면, 생장과 mRNA 방출에 결함을 보이진 않았지만 세포의 길이가 길어지는 형태를 보였다. Yeast two-hybrid 분석에서 Cdc31 단백질은 TREX-2 복합체의 또 다른 구성인자인 Sac3 그리고 Pci2와 상호작용을 하였다. 이와 같은 결과들은 S. pombe의 Cdc31 단백질도 역시 TREX-2 복합체의 구성인자로 mRNA 방출에 관여하고 있음을 시사한다.

• Journal of Microbiology
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• 제39권4호
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• pp.286-292
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• 2001

During mitosis. the proper segregation of duplicated chromosomes is corrdinated by a spindle check-point. The bifurcated spindle checkpoint blocks cell cycle progression at metaphase by monitoring unattached kinetochores and inhibits mitotic exit in response to the misorientation of the mitotic spin- dle Ibd1p/Bfa1p is a spindle checkpoint regulator of budding yeast in the Bub2p checkpoint pathway for mitotic exit and its disruption abolishes mitotic arrest when proper organization of the mitotic spin-dls inhibited. Ibd1p/Bfa1p localizes to the spindle pole body, a microtublue-organizing center in yeast, and its overexpression arrests the cell cycle in 80% of cells with an enlarged budy at mitosis and in 20 % of cells with multiple buds. In this study, we found that the C-terminus of Ibd1p/Bfa1p phys-ically interacts with Skp1p, a key component of SCF (Skp1/cullin/F-box) complex for ubiquition-medi-ated proteolysis of cel cycle regulatores as well as an evolutionally conserved kinetochore protein for cell cycle progression. A putative F-box motif was found in the C-terminus of Ibd1p/Bfa1p and its function was investigated by making mutants of conserved residues in the motif. These Ibd1p/Bfa1p mutants of a putative F-box interacted with SKp1p in vitro by two-hybrid assays as wild type Ibd1p/Bfa1p. Also these Ibd1p/Bfa1p utants displayed the overexpression phenotypes of wild type Ibd1p, when over-expressed under inducible promoters . These results suggest that a putative F-box motif of Ibd1p/Bfa1p is not essential for the interaction with SKp1p and its function in mitotic exit and cytokinesis.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.162.2-162.2
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• 2003

Microtubule-organizing center (MOTC) plays pivotal roles in cell division process. Integrity of the spindle pole body (SPB) in Saccharomyces cerevisiae is required for migration and separation of sister chromatids in mitotic phase. Role of an essential SPB component, Spcl05, is poorly understood. Here we show that throughout all stage of cell division cycle, GFP-tagged Spcl05p localizes at SPB and its protein stability is fluctuated with mitosis-specific modifications. To gain new insights into the function of Spc105, we generated and characterized novel temperature sensitive spc105 mutants. (omitted)

• BMB Reports
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• 제45권8호
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• pp.427-432
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• 2012

Primary cilia, single hair-like appendage on the surface of the most mammalian cells, were once considered to be vestigial cellular organelles for a past century because of their tiny structure and unknown function. Although they lack ancestral motility function of cilia or flagella, they share common ground with multiciliated motile cilia and flagella on internal structure such as microtubule based nine outer doublets nucleated from the base of mother centrioles called basal body. Making cilia, ciliogenesis, in cells depends on the cell cycle stage due to reuse of centrioles for cell division forming mitotic spindle pole (M phase) and assembling cilia from basal body (starting G1 phase and maintaining most of interphase). Ciliary assembly required two conflicting processes such as assembly and disassembly and balance between these two processes determines the length of cilia. Both process required highly conserved transport system to supply needed substance to grow tip of cilia and bring ciliary turnover product back to the base of cilia using motor protein, kinesin and dynein, and transport protein complex, IFT particles. Disruption of ciliary structure or function causes multiple human disorder called ciliopathies affecting disease of diverse ciliated tissues ranging from eye, kidney, respiratory tract and brain. Recent explosion of research on the primary cilia and their involvement on animal development and disease attracts scientific interest on how extensively the function of cilia related to specific cell physiology and signaling pathway. In this review, I introduce general features of primary cilia and recent progress in understanding of the ciliary length control and signaling pathways transduced through primary cilia in vertebrates.