• 생명과학회지
• /
• 제19권7호
• /
• pp.968-975
• /
• 2009

본 연구에서는 8주의 유산소 및 저항성 트레이닝 그룹으로 나누고 그에 따른 트레이닝이 서로 다른 테스트를 하였을 때, 운동 특이성 효과(specific effect)와 전사효과(transferabilty)에 영향을 미치는 지를 연구하였다. 결론적으로 8주간의 유산소 및 저항성 트레이닝은 동일한 테스트를 통하여 운동의 특이성은 나타냈으나 서로 다른 테스트를 해 봄으로써 전사효과의 향상은 나타내지 못했다. 전사효과를 나타내지 못한 가장 큰 이유는 8주라는 기간이 중추신경과 근육의 적응하기에는 다소 짧은 기간이라 사료되며 추후의 연구에서는 트레이닝 기간등을 고려한 좀 더 세분화된 연구가 필요하다고 생각된다.

• BMB Reports
• /
• 제54권2호
• /
• pp.118-123
• /
• 2021

The bacterial effector protein RavZ from a pathogen can impair autophagy in the host by delipidating the mammalian autophagy-related gene 8 (mATG8)-phosphatidylethanolamine (PE) on autophagic membranes. In RavZ, the membrane-targeting (MT) domain is an essential function. However, the molecular mechanism of this domain in regulating the intracellular localization of RavZ in cells is unclear. In this study, we found that the fusion of the green fluorescent protein (GFP) to the MT domain of RavZ (GFP-MT) resulted in localization primarily to the cytosol and nucleus, whereas the GFP-fused duplicated-MT domain (GFP-2xMT) localized to Rab5- or Rab7-positive endosomes. Similarly, GFP fusion to the catalytic domain (CA) of RavZ (GFP-CA) resulted in localization primarily to the cytosol and nucleus, even in autophagy-induced cells. However, by adding the MT domain to GFP-CA (GFP-CA-MT), the cooperation of MT and CA led to localization on the Rab5-positive endosomal membranes in a wortmannin-sensitive manner under nutrient-rich conditions, and to autophagic membranes in autophagy-induced cells. In autophagic membranes, GFP-CA-MT delipidated overexpressed or endogenous mATG8-PE. Furthermore, GFP-CA△α3-MT, an α3 helix deletion within the CA domain, failed to localize to the endosomal or autophagic membranes and could not delipidate overexpressed mATG8-PE. Thus, the CA or MT domain alone is insufficient for stable membrane localization in cells, but the cooperation of MT and CA leads to localization to the endosomal and autophagic membranes. In autophagic membranes, the CA domain can delipidate mATG8-PE without requiring substrate recognition mediated by LC3-interacting region (LIR) motifs.

• Molecules and Cells
• /
• 제40권1호
• /
• pp.54-65
• /
• 2017

Although cancer/testis antigen DDX53 confers anti-cancer drug-resistance, the effect of DDX53 on cancer stem cell-like properties and autophagy remains unknown. MDA-MB-231 ($CD133^+$) cells showed higher expression of DDX53, SOX-2, NANOG and MDR1 than MDA-MB-231 ($CD133^-$). DDX53 increased in vitro self-renewal activity of MCF-7 while decreasing expression of DDX53 by siRNA lowered in vitro self-renewal activity of MDA-MB-231. DDX53 showed an interaction with EGFR and binding to the promoter sequences of EGFR. DDX53 induced resistance to anti-cancer drugs in MCF-7 cells while decreased expression of DDX53 by siRNA increased the sensitivity of MDA-MB-231 to anti-cancer drugs. Negative regulators of DDX53, such as miR-200b and miR-217, increased the sensitivity of MDA-MB-231 to anti-cancer drugs. MDA-MB-231 showed higher expression of autophagy marker proteins such as ATG-5, $pBeclin1^{Ser15}$ and LC-3I/II compared with MCF-7. DDX53 regulated the expression of marker proteins of autophagy in MCF-7 and MDA-MB-231 cells. miR-200b and miR-217 negatively regulated the expression of autophagy marker proteins. Chromatin immunoprecipitation assays showed the direct regulation of ATG-5. The decreased expression of ATG-5 by siRNA increased the sensitivity to anti-cancer drugs in MDA-MB-231 cells. In conclusion, DDX53 promotes stem cell-like properties, autophagy, and confers resistance to anti-cancer drugs in breast cancer cells.

• 생명과학회지
• /
• 제7권3호
• /
• pp.167-171
• /
• 1997

번역개시 및 인산화의 조절에 관여하는 RNA와 단백질의 결합 및 인식기작을 연구하기 위해서[$\alpha$^{-32}$P] UMP-labeled HIV Rev-responsive element(RRE) RNA를 이용한 affinity screening에 이해서 Hela ZA-PII cDNA library로부터 이중선RNA결합단백질의 cDNA (RBFII)를 분리하였다. RBFII의 cDNA에 대한 염기서열을 결정하였으며 기존에 연구된 바 있는 RBFII(RBF 또는 TRBP로 보고되었으며 본 연구에서는 RBFII와 구분하기 위해 RBFI으로 명명)과 대부분의 경우 공통적인 ORF를 지니는 것으로 나타났다. 그러나 5’말단에서는 공통적인 ORF 가 RBFI의 경우 21개의 아미노산을 의미하는 63 nt가 Lac-Z의 N-말단에 연결된데 비해서 특이한 46개 아미노기를 의미하는 138nt가 존재함이 밝혀졌다. 5’-말단에 처음 나타나는 ATG 및 부근의 염기서열을 분석해 볼 때 양 cDNA는 5’말단이 완전하지 않은 것으로 사료된다.

• The Korean Journal of Physiology and Pharmacology
• /
• 제27권5호
• /
• pp.449-456
• /
• 2023

N-methyl-D-aspartate (NMDA) receptors are ionic glutamine receptors involved in brain development and functions such as learning and memory formation. NMDA receptor inhibition is associated with autophagy activation. In this study, we investigated whether the NMDA receptor antagonists, memantine and ifenprodil, induce autophagy in human retinal pigment epithelial cells (ARPE-19) to remove N-retinylidene-N-retinylethanolamine (A2E), an intracellular lipofuscin component. Fluorometric analysis using labeled A2E (A2E-BDP) and confocal microscopic examination revealed that low concentrations of NMDA receptor antagonists, which did not induce cytotoxicity, significantly reduced A2E accumulation in ARPE-19 cells. In addition, memantine and ifenprodil activated autophagy in ARPE-19 cells as measured by microtubule-associated protein 1A/1B-light chain3-II formation and phosphorylated p62 protein levels. Further, to understand the correlation between memantine- and ifenprodil-mediated A2E degradation and autophagy, autophagy-related 5 (ATG5) was depleted using RNA interference. Memantine and ifenprodil failed to degrade A2E in ARPE-19 cells lacking ATG5. Taken together, our study indicates that the NMDA receptor antagonists, memantine and ifenprodil, can remove A2E accumulated in cells via autophagy activation in ARPE-19 cells.

• Journal of Microbiology and Biotechnology
• /
• 제30권9호
• /
• pp.1412-1419
• /
• 2020

Human noroviruses (HuNoVs) are a leading cause of gastroenteritis outbreaks worldwide. However, the paucity of appropriate cell culture models for HuNoV replication has prevented developing effective anti-HuNoV therapies. In this study, first, the replication of the virus at various temperatures in different cells was compared, which showed that lowering the culture temperature from 37℃ significantly increased virus replication in Madin-Darby canine kidney (MDCK) cells. Second, the expression levels of autophagy-, immune-, and apoptosis-related genes at 30℃ and 37℃ were compared to explore factors affecting HuNoV replication. HuNoV cultured at 37℃ showed significantly increased autophagy-related genes (ATG5 and ATG7) and immune-related genes (IFNA, IFNB, ISG15, and NFKB) compared to mock. However, the virus cultured at 30℃ showed significantly decreased expression of autophagy-related genes (ATG5 and ATG7), but not significantly different major immune-related genes (IFNA, ISG15, and NFKB) compared to mock. Importantly, expression of the transcription factor FOXO1, which controls autophagy- and immune-related gene expression, was significantly lower at 30℃. Moreover, FOXO1 inhibition in temperature-optimized MDCK cells enhanced HuNoV replication, highlighting FOXO1 inhibition as an approach for successful virus replication. In the temperature-optimized cells, various HuNoV genotypes were successfully replicated, with GI.8 showing the highest replication levels followed by GII.1, GII.3, and GII.4. Furthermore, ultrastructural analysis of the infected cells revealed functional HuNoV replication at low temperature, with increased cellular apoptosis and decreased autophagic vacuoles. In conclusion, temperature-optimized MDCK cells can be used as a convenient culture model for HuNoV replication by inhibiting FOXO1 and providing adaptability to different genotypes.

• Asian Pacific Journal of Cancer Prevention
• /
• 제14권12호
• /
• pp.7537-7542
• /
• 2013

Background: Terpinen-4-ol, a monoterpene, is found as the main component of essential oil extracts from many plants. In this study apoptotic and autophagic types of cell death induced by terpinen-4-ol and associated mechanisms were investigated in human leukemic HL-60 cells. Materials and Methods: The cytotoxicity of human leukemic U937 and HL-60 cells was determined by MTT assay. Cytochrome c release, expression of Bax, Bcl-2, Bcl-xl and cleaved Bid were determined by Western blotting. Cell morphology was examined under a transmission electron microscope. LC3-I/II, ATG5 and Beclin-1 levels were detected by immunoblotting. Results: Terpinen-4-ol exhibited cytotoxicity to human leukemic HL-60 but not U937 cells. The apoptotic response to terpinen-4-ol in HL-60 cells was due to induction of cytochrome c release from mitochondria and cleavage of Bid protein after the stimulation of caspase-8. There was a slightly decrease of Bcl-xl protein level. The characteristic cell morphology of autophagic cell death was demonstrated with multiple autophagosomes in the cytoplasm. At the molecular level, the results from Western blot analysis showed that terpinen-4-ol significantly induced accumulation of LC3-I/II, ATG5 and Beclin-1, regulatory proteins required for autophagy in mammalian cells. Conclusions: Terpinen-4-ol induced-human leukemic HL-60 cell death was via both autophagy and apoptosis.

• Asian Pacific Journal of Cancer Prevention
• /
• 제17권1호
• /
• pp.377-380
• /
• 2016

Background: Epidemiological data on thyroid cancer and associated risk factors are scarce in our setting. The present study was therefore designed to gather data which could be helpful in providing insights to thyroid physicians and surgeons for better management of affected patients. Purpose: To determine the frequency of carcinoma thyroid among patients presenting with goiter and its association with TSH, Tg/ATg and other demographic factors. Materials and Methods: A total of 73 adult patients of either gender with solitary solid cold nodules and/or multi-ndoular goiter (MNG) with predominant solid cold nodules were enrolled. All surgically resected samples were sent for histopathology. The frequency of thyroid cancer and its subtypes was noted and tested for association with gender, age (< or ${\geq}40years$), recent increase in swelling size, TSH, Tg and ATg. Results: Thyroid cancer was diagnosed in 26% (n=19) of the patients, 14 (73.7%) being diagnosed with papillary thyroid cancer and 5 (26.3%) with follicular thyroid cancer. No other subtypes were noted. Presence of thyroid cancer was significantly associated with recent increase in swelling size and higher TSH Values mean TSH values (P<0.05). No significant association was found with gender, age, Tg and ATg values (P>0.05). Conclusions: Overall percentage of thyroid cancer in our study sample was found to be 26%, with a predominance of papillary over follicular lesions. Rates were significantly higher in patients who had history of recent increase in swelling size and higher and higher pre-surgery TSH values.

• Biomolecules & Therapeutics
• /
• 제30권5호
• /
• pp.447-454
• /
• 2022

Few studies have evaluated the role of autophagy in the development of oxaliplatin (OXT) resistance in colon cancer cells. In this study, we compared the role of autophagy between SNU-C5 colon cancer cells and OXT-resistant SNU-C5 (SNU-C5/OXTR) cells. At the same concentration of OXT, the cytotoxicity of OXT or apoptosis was significantly reduced in SNU-C5/OXTR cells compared with that in SNU-C5 cells. Compared with SNU-C5 cells, SNU-C5/OXTR cells exhibited low levels of autophagy. The expression level of important autophagy proteins, such as autophagy-related protein 5 (Atg5), beclin-1, Atg7, microtubule-associated proteins 1A/1B light chain 3B I (LC3-I), and LC3-II, was significantly lower in SNU-C5/OXTR cells than that in SNU-C5 cells. The expression level of the autophagy-essential protein p62 was also lower in SNU-C5/OXTR cells than in SNU-C5 cells. In SNU-C5/OXTR cells, the production of intracellular reactive oxygen species (ROS) was significantly higher than that in SNU-C5 cells, and treatment with the ROS scavenger N-acetylcysteine restored the reduced autophagy levels. Furthermore, the expression of antioxidant-related nuclear factor erythroid 2-related factor 2 transcription factor, heme oxygenase-1, and Cu/Zn superoxide dismutase were also significantly increased in SNU-C5/OXTR cells. These findings suggest that autophagy is significantly reduced in SNU-C5/OXTR cells compared with SNU-C5 cells, which may be related to the production of ROS in OXT-resistant cells.

• Journal of Microbiology and Biotechnology
• /
• 제8권3호
• /
• pp.284-286
• /
• 1998

A ura5 gene encoding Orotate Phosphoribosyl Transferase (OPRTase) of Metarhizium anisopliae was cloned by PCR methods and sequenced. The sequenced ura 5 gene encodes a polypeptide of 234 amino acid residues. This deduced amino acid sequence showed high similarity to other fungi OPRTase and there was no intron sequence between ATG starting codon and TGA ending codon.