• Journal of Microbiology and Biotechnology
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• 제18권8호
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• pp.1416-1422
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• 2008

Epothilone and its analogs are a potent new class of anticancer compounds produced by myxobacteria. Thus, in an effort to identify new myxobacterial strains producing epothilone and its analogs, cellulose-degrading myxobacteria were isolated from Korean soils, and 13 strains carrying epothilone biosynthetic gene homologs were screened using a polymerase chain reaction. A migration assay revealed that Sorangium cellulosum KYC3013, 3016, 3017, and 3018 all produced microtubule-stabilizing compounds, and an LC-MS/MS analysis showed that S. cellulosum KYC3013 synthesized epothilone A.

• 한국자기공명학회논문지
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• 제15권2호
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• pp.104-114
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• 2011

Rapid exchange and hydrolysis of the tubulin-bound guanine nucleotides have been known to govern the dynamics of microtubules. However, the instability and low concentration have made it difficult for the microtubule-bound GTP to be observed directly. In this study, we circumvent these problems by lyophilization and using cross-polarization techniques. $^{31}P$ NMR signals were detected from the tubulin-bound GTP in microtubules for the first time. Analysis of the $^{31}P$ CPMAS NMR spectrum indicates that GTP hydrolysis was delayed by the presence of taxol.

• Asian Pacific Journal of Cancer Prevention
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• 제16권15호
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• pp.6535-6539
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• 2015

This study was designed to assess, whether a new chemotherapeutic microtubule inhibitor, Epothilone B (EpoB, Patupilone), can induce DNA damage in normal ovarian cells (MM14.Ov), and to evaluate if such damage could be repaired. The changes were compared with the effect of paclitaxel (PTX) commonly employed in the clinic. The alkaline comet assay technique and TUNEL assay were used. The kinetics of DNA damage formation and the level of apoptotic cells were determined after treatment with IC50 concentrations of EpoB and PTX. It was observed that PTX generated significantly higher apoptotic and genotoxic changes than EpoB. The peak was observed after 48 h of treatment when the DNA damage had a maximal level. The DNA damage induced by both tested drugs was almost completely repaired. As EpoB in normal cells causes less damage to DNA it might be a promising anticancer drug with potential for the treatment of ovarian tumors.

• 식품기술
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• 제17권4호
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• pp.117-128
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• 2004

Sulforaphane은 브로컬리나 십자화과 채소중의 glucoraphanin의 가수분해 산물인 isothiocyanate로서 이는 detoxification 효소의 phase II를 일으키는 것으로 나타났고 설치류에서 화학적으로 발생된 유선 종양을 억제하고 최근에는 대장암 세포에서 cell cycle arrest와 apoptosis를 일으킨다고 알려져 왔다. 여기서는 SUL이 Human MammaryMCF-7 adenocarcinoma 세포의 증폭을 억제하는 역할을 제시하였다. MCF-7 cell에 15umol/L SUL을 처리하였을 때 G2/M cell cycle이 arrest를 보였고 cyclin B1 protein이 24시간 이내에 증가하였다. 15umol/L의 SUL은 in vivo 상에서 histon Hl의 인산화를 유도하고, 초기 mitosis에서 cell을block하며 mitotic microtuble의 중합화를 방해하였다. In vitro 상에서 정제된 bovine braintubulin에 대한 SUL을 고농도로 투여했을 때, tubulin의 중합율과 총 tubulin 중합도의 억제를 보였다. 덧붙여서, isothiocyanate를 함유하는 SULanalog로 처리된 정제 tubulin도 비슷하게 저해를 받았다. 본 연구는 SUL이 mitotic cell cyclearrest를 포함한 mammary cancer 억제력을 가진 것과, 이러한 기작으로 정상적인 tubulin 중합화및 microtubule dynamic에 한층 효과적인 영향을 준다는 것을 제시하였다.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2005년도 춘계 국제심포지엄 및 학술대회
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• pp.172-172
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• 2005

• Applied Microscopy
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• 제7권1호
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• pp.13-20
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• 1977

방아깨비의 종형유충을 재료로 하여 혈구의 미세구조를 관찰한 바 4 가지의 혈구 형태를 구분해 냈다. Prohemocyte는 크기가 가장 작으며 미분화된 소기관을 가졌고 Plasmatocyte는 그 수가 비교적 많고 발달된 소기관을 가졌으며, Granular cell 은 방추형 또는 난형으로 세포질내에 몇가지 과립을 가진 것이 특징이다. Adipohemocyte는 많은 지방과립을 함유하고 microtubule 특징적으로 나타났다.

• Molecules and Cells
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• 제20권2호
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• pp.256-262
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• 2005

The neuronal cytoskeleton is essential for establishment of neuronal polarity, but mechanisms controlling generation of polarity in the cytoskeleton are poorly understood. The nonreceptor tyrosine kinase, Fer, has been shown to bind to microtubules and to interact with several actin-regulatory proteins. Furthermore, Fer binds p120 catenin and has been shown to regulate cadherin function by modulating cadherin-${\beta}$-catenin interaction. Here we show involvement of Fer in neuronal polarization and neurite development. Fer is concentrated in growth cones together with cadherin, ${\beta}$-catenin, and cortactin in stage 2 hippocampal neurons. Inhibition of Fer-p120 catenin interaction with a cell-permeable inhibitory peptide (FerP) increases neurite branching. In addition, the peptide significantly delays conversion of one of several dendrites into an axon in early stage hippocampal neurons. FerP-treated growth cones also exhibit modified localization of the microtubule and actin cytoskeleton. Together, this indicates that the Fer-p120 interaction is required for normal neuronal polarization and neurite development.

• BMB Reports
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• 제47권12호
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• pp.660-665
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• 2014

Stathmin 1 is a microtubule destabilizer that plays an important role in cell cycle progression, segregation of chromosomes, clonogenicity, cell motility and survival. Stathmin 1 overexpression has been reported in malignant hematopoietic cells and Stathmin 1 inhibition reduces the highly proliferative potential of leukemia cell lines. However, during the differentiation of primary hematopoietic cells, Stathmin 1 expression decreases in parallel to decreases in the proliferative potential of early hematopoietic progenitors. The scope of the present review is to survey the current knowledge and highlight future perspectives for Stathmin 1 in normal and malignant hematopoiesis, with regard to the expression, function and clinical implications of this protein.

• 한국동물학회지
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• 제37권1호
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• pp.40-48
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• 1994

세포분화에 따른 Small GTP-binding protein의 역할을 밝히기 위하여 Retinoic acid(RA)와 dibutyryl cyclic AMP(dbcAMP)로 분화를 유도한 F9 기형암종세포의 형태적인 변화와 함께 Small GTP-binding protein의 분포를 조사하였다. RA와 dbcAMP를 처리한 세포는 분화유도 5일경(초기 분화 단계)에 분명한 세포의 경계를 보이기 시작하여 7일경(분화 후기 단계)에는 거의 모든 세포가 등근 분화된 형태로 전환되었다. 이 분화과정 동안 세포막에는 많은 microvilli와 lamellopodia 같은 구조물이 나타났다. 아울러 초기 분화 단계에 많은 량의 laminin이 발현되었으며 분화 후기에 microtubule의 재분포가 관찰되었다. 세종류의 Small GTP-binding protein(25 23, 21 KD)이 F9 세포의 막성분과 세포질에서 관찰되었으며 분화가 진행됨에 따라서 세단백질 모두 증가되는 양상을 보였다 이러한 결과는 Small GTP-binding protein이 F9 세포의 분화에 특별한 기능을 가지고 있음을 시사해 주고 있다.

• Bulletin of the Korean Chemical Society
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• 제34권5호
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• pp.1503-1507
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• 2013

The two major symptoms characterizing Alzheimer's disease are the formation of amyloid-${\beta}$ extracellular deposits in the form of senile plaques and intracellular neurofibrillary tangles (NFTs) that consist of pathological hyperphosphorylated tau protein aggregated into insoluble paired helical filaments (PHFs). Neurons of the central nervous system have appreciable amounts of tau protein, a microtubule-associated protein. To maintain an optimal operation of nerves, the microtubules are stabilized, which is necessary to support cell structure and cellular processes. When the modified tau protein becomes dysfunctional, the cells containing misfolded tau cannot maintain cell structure. One of the pathological hallmarks of Alzheimer's disease is hyperphosphorylated tau protein. This paper shows that the small heat shock protein from humans (Hsp27) reduces hyperphosphorylated tau and prevents hyperphosphorylated tau-induced cell death of the human neuroblastoma cell line SH-SY5Y.