• Asian Pacific Journal of Cancer Prevention
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• 제15권22호
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• pp.9593-9597
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• 2014

Ursolic acid, extracted from the traditional Chinese medicine bearberry, can induce apoptosis of gastric cancer cells. However, its pro-apoptotic mechanism still needs further investigation. More and more evidence demonstrates that mitochondrial translocation of cofilin-1 appears necessary for the regulation of apoptosis. Here, we report that ursolic acid (UA) potently induces the apoptosis of gastric cancer SGC-7901 cells. Further mechanistic studies revealed that the ROCK1/PTEN signaling pathway plays a critical role in UA-mediated mitochondrial translocation of cofilin-1 and apoptosis. These findings imply that induction of apoptosis by ursolic acid stems primarily from the activation of ROCK1 and PTEN, resulting in the translocation of cofilin-1 from cytoplasm to mitochondria, release of cytochrome c, activation of caspase-3 and caspase-9, and finally inducing apoptosis of gastric cancer SGC-7901 cells.

• The Korean Journal of Physiology and Pharmacology
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• 제16권3호
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• pp.159-165
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• 2012

Squamous cell carcinoma (SCC) and adenocarcinoma (AC) are the major histological types of non-small cell lung carcinoma (NSCLC). Although both SCCs and ACs have been characterized histologically and clinically, the precise mechanisms underlying their migration and invasion are not yet known. Here, we address the involvement in NSCLC of the p21-associated kinase1 (Pak1)/LIM kinase1 (LIMK1)/cofilin pathway, which recently has been reported to play a critical role in tumor migration and invasion. The Pak1/LIMK1/cofilin pathway was evaluated in tumors from SCC (n=35) and AC (n=35) patients and in SCC- and AC-type cell lines by western blotting, immunohistochemistry, and in vitro migration and invasion assays. The levels of phosphorylated Pak1, LIMK1, and cofilin in lung tumor tissues from SCC patients were increased as compared to normal tissues. In addition, immunohistochemistry showed greater expression of phosphorylated cofilin in SCC tissues. Expression of phosphorylated Pak1 and LIMK1 proteins was also significantly higher in SCC-type cells than in AC-type cells. Moreover, migration and invasion assays revealed that a higher percentage of SCC type cells exhibited migration and invasion compared to AC type cells. Migration was also decreased in LIMK1 knockdown SK-MES-1 cells. These findings suggest that the activation of the Pak1/LIMK1/cofilin pathway could preferentially contribute to greater tumor migration and invasion in SCC, relative to that in AC.

• BMB Reports
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• 제54권12호
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• pp.614-619
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• 2021

Hepatitis B virus (HBV) infection is a major cause of hepatocellular carcinoma (HCC), which is a highly aggressive cancer. HBV X protein (HBx), one of four HBV gene products, plays pivotal roles in the development and metastasis of HCC. It has been reported that HBx induces liver cancer cell migration and reorganizes actin cytoskeleton, however the molecular basis for actin cytoskeleton reorganization remains obscure. In this study, we for the first time report that HBx promotes actin polymerization and liver cancer cell migration by regulating calcium modulated protein, calmodulin (CaM). HBx physically interacts with CaM to control the level of phosphorylated cofilin, an actin depolymerizing factor. Mechanistically, HBx interacts with CaM, liberates Hsp90 from its inhibitory partner CaM, and increases the activity of Hsp90, thus activating LIMK1/cofilin pathway. Interestingly, the interaction between HBx and CaM is calcium-dependent and requires the CaM binding motif on HBx. These results indicate that HBx modulates CaM which plays a regulatory role in Hsp90/LIMK1/cofilin pathway of actin reorganization, suggesting a new mechanism of HBV-induced HCC metastasis specifically derived by HBx.

• 한국발생생물학회지:발생과생식
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• 제26권1호
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• pp.23-36
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• 2022

Pharyngeal pouches, a series of outgrowths of the pharyngeal endoderm, are a key epithelial structure governing facial skeleton development in vertebrates. Pouch formation is achieved through collective cell migration and rearrangement of pouch-forming cells controlled by actin cytoskeleton dynamics. While essential transcription factors and signaling molecules have been identified in pouch formation, regulators of actin cytoskeleton dynamics have not been reported yet in any vertebrates. Cofilin1-like (Cfl1l) is a fish-specific member of the Actin-depolymerizing factor (ADF)/Cofilin family, a critical regulator of actin cytoskeleton dynamics in eukaryotic cells. Here, we report the expression and function of cfl1l in pouch development in zebrafish. We first showed that fish cfl1l might be an ortholog of vertebrate adf, based on phylogenetic analysis of vertebrate adf and cfl genes. During pouch formation, cfl1l was expressed sequentially in the developing pouches but not in the posterior cell mass in which future pouch-forming cells are present. However, pouches, as well as facial cartilages whose development is dependent upon pouch formation, were unaffected by loss-of-function mutations in cfl1l. Although it could not be completely ruled out a possibility of a genetic redundancy of Cfl1l with other Cfls, our results suggest that the cfl1l expression in the developing pouches might be dispensable for regulating actin cytoskeleton dynamics in pouch-forming cells.

• Mycobiology
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• 제43권3호
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• pp.272-279
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• 2015

To screen molecular chaperones similar to small heat shock proteins (sHsps), but without ${\alpha}$-crystalline domain, heat-stable proteins from Schizosaccharomyces pombe were analyzed by 2-dimensional electrophoresis and matrix assisted laser desorption/ionization time-of-flight mass spectrometry. Sixteen proteins were identified, and four recombinant proteins, including cofilin, NTF2, pyridoxin biosynthesis protein (Snz1) and Wos2 that has an ${\alpha}$-crystalline domain, were purified. Among these proteins, only Snz1 showed the anti-aggregation activity against thermal denaturation of citrate synthase. However, pre-heating of NTF2 and Wos2 at $70^{\circ}C$ for 30 min, efficiently prevented thermal aggregation of citrate synthase. These results indicate that Snz1 and NTF2 possess molecular chaperone activity similar to sHsps, even though there is no ${\alpha}$-crystalline domain in their sequences.

• 한국임상수의학회지
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• 제28권1호
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• pp.75-80
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• 2011

Proteomics is a useful approach to know protein expression, post-translational modification and protein function. We investigated the protein expression pattern and identity in pigs fed with the tissue culture medium waste after harvest of Korean wild ginseng (TCM-KWG) (Panax ginseng). Two groups (n = 30/group) of pigs were administered with 0 (control) and 16 ml/L (treatment) TCM-KWG through drinking water. After 4 weeks, we examined the protein expression pattern of longissimus dorsi muscle by Two-dimensional electrophoresis analysis. TCM-KWG treatment significantly increased two spot's density, and markedly reduced one spot's density in the muscles. We identified 3 proteins (heat shock protein 90-alpha, myosin binding protein and cofilin 2) by the ESI-MS/MS (Q-TOF2, Micromass). These results demonstrate that TCM-KWG treatment may play a protection role against physiological stress in pigs, like as increased heat shock protein 90-alpha.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 추계수산관련학회 공동학술대회발표요지집
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• pp.175-176
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• 2000

PtdIns(4)P와 PtdIns(4,5)P$_2$등과 같은 폴리포스이노시타이드(Polyphosph-oinositide)는 여러 가지 호르몬 및 성장인자들에 의한 세포의 신호전달기작에 있어서 중요한 역할을 한다. 이들은 세포내 여러효소 및 단백질의 활성을 조절하기도 하고, cofilin(1), destrin(2), $\alpha$-actinin(3), gCap39(4) 및 CapZ등과 같은 여러 actin binding protein들의 성질을 변화시키기도 한다. (중략)

• 생명과학회지
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• 제21권10호
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• pp.1401-1406
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• 2011

면역세포는 외부 병원체 감염, 자연적 순환에 대하여 형태변화를 수반한다. T세포는 염증, 면역 감시, 이동, 그리고 혈관통과를 위해 uropod, filopodia, lamellipodia, 및 microvilli를 생산한다. 짧고 손가락 처럼 생긴 microvilli는 순환하고 있는 포유동물 면역세포 표면을 덮고 있다. 단핵세포와 호중구의 세포표면은 많이 다른데 membrane ruffle을 함유하고 있다. 본 연구는, T세포의 microvilli에 대하여 actin cytoskeleton과의 연관성에 대하여 탐구하였다. Actin 파괴자인 cytochalasin D 처리 후 SEM관찰을 통해서, Jurkat T세포의 microvilli를 보면 빠르게 사라지는 것을 알 수 있었다. 이와는 대조적으로 RhoA의 activator인 PMA는 LIMK와 cofilin 신호 전달을 통해서 microvilli 두께가 확장되는 것을 관찰 하였다. 또한, cytochalasin D 처리는 EL4 T세포의 극성을 사라지게 하는 것으로 보아 F-actin은 T세포의 극성 유지에도 영향을 미친다. 이상의 결과는 Actin cytoskeleton은 T세포에서 microvilli와 극성 유지에 관여하고 있는 것을 제시한다.

• 대한의생명과학회지
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• 제26권1호
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• pp.1-7
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• 2020

Alzheimer's disease (AD) is the most common neurodegenerative disorder and is expected to become more and more widespread as life expectancy increases. New therapeutic target, as well as the identification of mechanisms responsible for pathology, is urgently needed. Recently, microglial actin cytoskeleton has been proposed as a beneficial role in axon regeneration of brain injury. This review highlights in understanding of the characteristics of microglial actin cytoskeleton and discuss the role of specific actin-interacting proteins and receptors in AD. The precise mechanisms and functional aspects of motility by microglia require further study, and the regulation of microglial actin cytoskeleton might be a potential therapeutic strategy for neurological diseases.

• 생명과학회지
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• 제26권8호
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• pp.963-969
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• 2016

Kinesin superfamily proteins (KIFs)은 세포 내 소기관이나 단백질복합체를 미세소관을 따라 운반하는 모터단백질이다. Kinesin 1은 경쇄단위체(light chain subunit)를 통하여 결합함으로써 세포 내 소기관, 신경소포, 신경전달물질수용체, 신호전달단백질, mRNA 등 다양한 운반체를 운반하는 KIFs의 한 종류이다. Kinesin light chains (KLCs)은 모터기능이 없는 단위체로서 kinesin heavy chains (KHCs) 이량체와 결합하여 kinesin 1을 구성한다. KLCs은 여러 단백질과 결합하지만 아직 결합단백질이 충분히 밝혀지지 않았다. 본 연구에서 KLC1의 tetratricopeptide repeat (TPR) 영역과 결합하는 단백질을 분리하기 위하여 효모 two-hybrid 탐색을 수행한 결과 Wiskott-Aldrich syndrome의 원인단백질이며 액틴 세포골격 조절단백질인 WASP/WAVE family의 하나인 WAVE1을 분리하였다. WAVE1은 KLC1의 TPR 영역을 포함한 부위와 결합하지만 KHCs인 KIF5A, KIF5B, KIF5C와는 결합하지 않았다. 또한 KLC1은 WAVE1의 C-말단에 존재하는 verprolin/cofilin/acidic (VCA) 도메인과 결합하였으며, 다른 WAVE isoform인 WAVE2와 WAVE3과도 결합하였다. HEK-293T 세포에 WAVE1과 KLC1을 동시에 발현시켰을 때 두 단백질이 세포 내에서 같은 부위에 존재하며, WAVE1을 면역침강한 결과 KLC1뿐만 아니라 KIF5B가 같이 침강함을 확인하였다. 이러한 결과들은 kinesin 1이 WAVE 단백질복합체 혹은 WAVE로 덮여있는 운반체를 운반함을 시사한다.