• BMB Reports
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• 제40권4호
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• pp.554-561
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• 2007

Shen and colleagues (Lin et al., 2004) have recently shown that overexpression of the Drosophila DNA methyltransferase 2 isoform C, dDnmt2c, extended life span of fruit flies, probably due to increased expression of small heat shock proteins such as Hsp22 or Hsp26. Here, I demonstrate with immunoprecipitations that overexpressed dDnmt2c interacts with endogenous Hsp70 protein in vivo in S2 cells. However, its C-terminal half, dDnmt2c(178-345) forms approximately 10-fold more Hsp70-containing protein complexe than wild-type dDnmt2c. Overexpressed dDnmt2c(178-345) but not the full length dDnmt2c is able to increase endogenous mRNA levels of the small heat shock proteins, Hsp26 and Hsp22. I provide evidence that dDnmt2c(178-345) increases Hsp26 promoter activity via two heat shock elements, HSE6 and HSE7. Simultaneously overexpressed Hsp40 or a dominant negative form of heat shock factor abrogates the dDnmt2c(178-345)-dependent increase in Hsp26 transcription. The data support a model in which the activation of heat shock factor normally found as an inactive monomer bound to chaperones is linked to the overexpressed C-terminus of dDnmt2c. Despite the differences observed in flies and S2 cells, these findings provide a possible explanation for the extended lifespan in dDnmt2c-overexpressing flies with increased levels of small heat shock proteins.

• 한국초지학회:학술대회논문집
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• 한국초지조사료학회 2005년도 학술심포지엄, 제43회 학술발표회
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• pp.214-215
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• 2005

• Genomics & Informatics
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• 제7권1호
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• pp.26-31
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• 2009

Heat shock proteins are a class of molecular chaperones that can be found in nearly all organisms from Bacteria, Archaea and Eukarya domains. Heat shock proteins experience increased transcription during periods of heat induced osmotic stress and are involved in protein disaggregation and refolding as part of a cell's danger signaling cascade. Heat shock protein, Hsp20 is a small molecular chaperone that is approximately 20kDa in weight and is hypothesized to prevent aggregation and denaturation. Hsp20 can be found in several strains of Proteobacteria, which comprises the largest phyla of the Bacteria domain and also contains several medically significant bacterial strains. Genomic analyses were performed to determine a common evolutionary pattern among Hsp20 sequences in Proteobacteria. It was found that Hsp20 shared a common ancestor within and among the five subclasses of Proteobacteria. This is readily apparent from the amount of sequence similarities within and between Hsp20 protein sequences as well as phylogenetic analysis of sequences from proteobacterial and non-proteobacterial species.

• 대한임상검사과학회지
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• 제49권4호
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• pp.460-469
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• 2017

열충격 단백질(heat shock proteins, HSPs)은 다양한 종양에서 과발현 되고, 종양이 형성되는 과정이나 그 예후에 영향을 주며, 분자량에 따라 HSP27, HSP60, HSP90, HSP100 등으로 구분한다. Heat shock protein90은 세포 내 불안정한 단백질을 보호하는 역할을 통해 질병의 유지에 기여하는데, 정상 조직에 비해 종양 세포에서 높은 수준으로 발현된다고 보고되었다. 이에 본 연구에서는 우리나라 사망원인 1위인 폐암 중 비소세포 폐암에서 Heat shock protein90 family 발현과 비소세포 폐암환자의 임상적 특징과의 상관관계를 분석하여 종양의 생물학적 표지자로서의 가능성을 조사하였다. HSP90 family의 발현과 임상병리학적 특성 및 생존율과의 상관관계를 분석한 결과 $HSP90{\alpha}$는 림프혈관강 침윤이 되지 않은 환자에서 높은 발현을 보였고(p=0.014), $HSP90{\beta}$ 은 조직학적 형태에서 편평상피세포 암종에서 높은 발현을 보였으며(p=0.003), GRP94 은 분화도가 낮을수록 높은 발현을 나타내었다(p=0.048). 생존율은 $HSP90{\alpha}$, $HSP90{\beta}$, GRP94 모두 발현 차이에 대한 유의성이 없었다. 본 연구를 통해 miRNA-126, miRNA-155, miRNA-200c의 발현은 비소세포 폐암의 진단을 위한 생물학적 표지자 및 예후 인자로서 사용될 수 있을 것으로 사료된다. 그리고 비소세포 폐암의 치료용으로 HSP90 family가 고려되어야 할 것이며, GRP94가 종양의 예후예측을 위한 중요한 인자라 사료된다.

• Journal of Microbiology and Biotechnology
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• 제24권8호
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• pp.1118-1122
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• 2014

The present study shows that DR1114 (Hsp20), a small heat shock protein of the radiation-resistant bacterium Deinococcus radiodurans, enhances tolerance to hydrogen peroxide ($H_2O_2$) stress when expressed in Escherichia coli. A protein profile comparison showed that E. coli cells overexpressing D. radiodurans Hsp20 (EC-pHsp20) activated the redox state proteins, thus maintaining redox homeostasis. The cells also showed increased expression of pseudouridine (psi) synthases, which are important to the stability and proper functioning of structural RNA molecules. We found that the D. radiodurans mutant strain, which lacks a psi synthase (DR0896), was more sensitive to $H_2O_2$ stress than wild type. These suggest that an increased expression of proteins involved in the control of redox state homeostasis along with more stable ribosomal function may explain the improved tolerance of EC-pHsp20 to $H_2O_2$ stress.

• The Korean Journal of Physiology and Pharmacology
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• 제22권4호
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• pp.457-465
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• 2018

The expression of BCL-2 interacting cell death suppressor (BIS), an anti-stress or anti-apoptotic protein, has been shown to be regulated at the transcriptional level by heat shock factor 1 (HSF1) upon various stresses. Recently, HSF1 was also shown to bind to BIS, but the significance of these protein-protein interactions on HSF1 activity has not been fully defined. In the present study, we observed that complete depletion of BIS using a CRISPR/Cas9 system in A549 non-small cell lung cancer did not affect the induction of heat shock protein (HSP) 70 and HSP27 mRNAs under various stress conditions such as heat shock, proteotoxic stress, and oxidative stress. The lack of a functional association of BIS with HSF1 activity was also demonstrated by transient downregulation of BIS by siRNA in A549 and U87 glioblastoma cells. Endogenous BIS mRNA levels were significantly suppressed in BIS knockout (KO) A549 cells compared to BIS wild type (WT) A549 cells at the constitutive and inducible levels. The promoter activities of BIS and HSP70 as well as the degradation rate of BIS mRNA were not influenced by depletion of BIS. In addition, the expression levels of the mutant BIS construct, in which 14 bp were deleted as in BIS-KO A549 cells, were not different from those of the WT BIS construct, indicating that mRNA stability was not the mechanism for autoregulation of BIS. Our results suggested that BIS was not required for HSF1 activity, but was required for its own expression, which involved an HSF1-independent pathway.

• Current Research on Agriculture and Life Sciences
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• 제17권
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• pp.15-20
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• 1999

엽록제 small HSP의 기능을 조사하기 위하여 항상적으로 발현하는 형질전환 식물체를 작성하였다. 고온 스트레스 하에서의 형질전환 식물체의 고온내성을 chlorophyll 형광으로 측정하였다. Leaf disc를 고온조건에서 5분간 처리한 후, 광화학계 II의 불활성화를 나타내는 Fo 값의 증가 또는 Fv 값의 감소치를 조사하였다. 형질전환 식물체는 고온 스트레스 하에서의 이들 값의 증감율이 현격히 감소하였다. 또한 유식물체를 $52^{\circ}C$에서 45분간 처리한 후, $25^{\circ}C$에서 계속적으로 배양하였을 때, 비형질전환 식물체는 전부 고사하였으나, 형질전환 식물체의 약 80%는 생존하였다. 이러한 결과는 엽록체 small HSP가 고온 스트레스 하에서 광합성기구를 보호하는데 있어서 중요한 기능을 담당하고 있음을 나타낸다.

• 한국초지조사료학회지
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• 제40권4호
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• pp.285-290
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• 2020

To understand the role of small heat shock protein (sHSPs) in rice plant response to various stresses such as the heat and oxidative stresses, a cDNA encoding a 24.1 kDa mitochondrial small HSP (Oshsp24.1) was isolated from rice by rapid amplification of cDNA ends (RACE) PCR. The deduced amino acid sequence shows very high similarity with other plant small HSPs. DNA gel blot analysis suggests that the rice genome contains more than one copy of Oshsp24.1. High level of expression of Oshsp24.1 transcript was observed in rice seedlings in response to heat, methyl viologen, hydrogen peroxide, ozone, salt and heavy metal stresses. Recombinant OsHSP24.1 protein was produced in E. coli cells for biochemical assay. The protein formed oligomeric complex when incubated with Sulfo-EGS (ethylene glycol bis (succinimidyl succinate)). Our results shows that Oshsp24.1 has an important role in abiotic stress response and have potential for developing stress-tolerant plants.

• 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.

• 한국초지학회:학술대회논문집
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• 한국초지조사료학회 1999년도 제24회 정기총회 및 프로그램, 제37회 학술발표회 및 특별강연 초록
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• pp.71.2-72
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• 1999

고등식물에 있어서 엽록체에 존재하는 저 분자량 heat shock protein (smHSP)은 식물의 내열성 획득에 있어서 필수유전자임이 mutant를 이용한 유전학적인 연구에 의해 보고된 바 있다. 고온내성이 강한 작물인 벼로부터 엽록체 smHSP cDNA를 분리하고자 벼의 잎에서 분리한 mRNA로 작성한 cDNA library로부터 screening하였다. 선발된 smHSP cDNA는 1,026 bp의 염기로 구성되어 있었으며, 239개의 아미노산으로 구성되는 예상분자량 26.6 kDa의 단백질을 code하고 있었다. 또한 다른 식물로부터(중략)