• 생명과학회지
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• 제19권12호
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• pp.1731-1736
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• 2009

최근의 연구에서 생쥐에 장기간 서구식 사료를 급여했을 때 내인성 SHP 단백질의 수준이 증가함을 보고하였다. 또한 HepG2 세포배양을 통한 실험에서, CDCA 처리가 내인성 SHP 단백질의 수준을 증가시킬 뿐만 아니라 외인성으로 발현된 flag-SHP의 분해율을 감소시켰다. 그리고 HepG2 세포를 ad-flag-SHP로 유전자 형질전환 시켰을 때, 담즙산에 의해 유도되어진 소장 FGF-19이 외인성으로 발현된 flag-SHP 단백질의 반감기를 증가시켰다. 그러나 cholic acid와 FGF-19에 의한 내인성 SHP 단백질의 발현수준과 분해율은 생쥐 또는 배양된 간암세포주에서 아직 명확히 이해되고 있지 않다. 이 연구는 cholic acid의 처리가 생쥐에서 내인성 SHP 단백질의 수준에 미치는 영향과, FGF-19이 HepG2 세포주에서 내인성 SHP 단백질의 분해율에 미치는 영향을 조사하였다. 정상적인 사료를 급여한 대조군 생쥐에서의 내인성 SHP 단백질 수준과 비교하여, 0.5%의 cholic acid를 첨가한 사료를 급여한 생쥐에서는 12시간과 24시간의 처리기간 동안에 내인성 SHP 단백질의 수준이 증가하였다. 배양된 인간 간암세포주인 HepG2에서 CDCA의 처리는 CDCA를 처리하지 않은 대조군 세포주와 비교하여 내인성 SHP 단백질의 분해율을 유의성 있게 변화시키지 않았다. 한편 외인성 ad-flag-SHP 단백질에 대한 이전의 연구와 일치하게, HepG2 세포에 cyclohexamide를 처리하였을 때 FGF-19는 내인성 SHP 단백질의 분해율을 현저히 감소시켰다. 이러한 결과는 담즙산과 FGF-19 모두 생쥐의 간과 HepG2 세포주에서 내인성 SHP 단백질의 수준을 증가시킴을 제시한다.

• BMB Reports
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• 제48권3호
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• pp.184-189
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• 2015

Src homology 2-containing protein tyrosine phosphatase 2 (SHP-2) is known to protect neurons from neurodegeneration during ischemia/reperfusion injury. We recently reported that ROS-mediated oxidative stress promotes phosphorylation of endogenous SHP-2 in astrocytes and complex formation between caveolin-1 and SHP-2 in response to oxidative stress. To examine the region of SHP-2 participating in complex formation with caveolin-1, we generated three deletion mutant constructs and six point mutation constructs of SHP-2. Compared with wild-type SHP-2, binding of the N-SH2 domain deletion mutant of SHP-2 to p-caveolin-1 was reduced greatly, using flow cytometric competitive binding assays and surface plasmon resonance (SPR). Moreover, deletion of the N-SH2 domain of SHP-2 affected $H_2O_2$-mediated ERK phosphorylation and Src phosphorylation at Tyr 419 in primary astrocytes, suggesting that N-SH2 domain of SHP-2 is responsible for the binding of caveolin-1 and contributes to the regulation of Src phosphorylation and activation following ROS-induced oxidative stress in brain astrocytes.

• The Korean Journal of Physiology and Pharmacology
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• 제24권2호
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• pp.129-135
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• 2020

SHP2 is an unusual protein phosphatase that functions as an activator for several signaling pathways, including the RAS pathway, while most other phosphatases suppress their downstream signaling cascades. The physiological and pathophysiological roles of SHP2 have been extensively studied in the field of cancer research. Mutations in the PTPN11 gene which encodes SHP2 are also highly associated with developmental disorders, such as Noonan syndrome (NS), and cognitive deficits including learning disabilities are common among NS patients. However, the molecular and cellular mechanism by which SHP2 is involved in cognitive functions is not well understood. Recent studies using SHP2 mutant mice or pharmacological inhibitors have shown that SHP2 plays critical role in learning and memory and synaptic plasticity. Here, we review the recent studies demonstrating that SHP2 is involved in synaptic plasticity, and learning and memory, by the regulation of the expression and/or function of glutamate receptors. We suggest that each cell type may have distinct paths connecting the dots between SHP2 and glutamate receptors, and these paths may also change with aging.

• Asian Pacific Journal of Cancer Prevention
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• 제16권6호
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• pp.2219-2225
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• 2015

SHP1 negatively regulates the Janus kinase 2/signal transducer and activator of transcription (JAK2/STAT) signaling pathway, which is constitutively activated in myeloproliferative neoplasms (MPNs) and leukemia. Promoter hypermethylation resulting in epigenetic inactivation of SHP1 has been reported in myelomas, leukemias and other cancers. However, whether SHP1 hypermethylation occurs in MPNs, especially in Chinese patients, has remained unclear. Here, we report that aberrant hypermethylation of SHP1 was observed in several leukemic cell lines and bone marrow mononuclear cells from MPN patients. About 51 of 118 (43.2%) MPN patients including 23 of 50 (46%) polycythaemia vera patients, 20 of 50 (40%) essential thrombocythaemia and 8 of 18 (44.4%) idiopathic myelofibrosis showed hypermethylation by methylation-specific polymerase chain reaction. However, SHP1 methylation was not measured in 20 healthy volunteers. Hypermethylation of SHP1 was found in MPN patients with both positive (34/81, 42%) and negative (17/37, 45.9%) JAK2V617F mutation. The levels of SHP1 mRNA were significantly lower in hypermethylated samples than unmethylated samples, suggesting SHP1 may be epigenetically inactivated in MPN patients. Furthermore, treatment with 5-aza-2'-deoxycytidine (AZA) in K562 cells showing hypermethylation of SHP1 led to progressive demethylation of SHP1, with consequently increased reexpression of SHP1. Meanwhile, phosphorylated JAK2 and STAT3 were progressively reduced. Finally, AZA increased the expression of SHP1 in primary MPN cells with hypermethylation of SHP1. Therefore, our data suggest that epigenetic inactivation of SHP1 contributes to the constitutive activation of JAK2/STAT signaling. Restoration of SHP1 expression by AZA may contribute to clinical treatment for MPN patients.

• 한국학교보건학회지
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• 제31권3호
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• pp.157-166
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• 2018

Purpose: This review aimed to provide a new perspective on School Heath Promotion (SHP) in the context of Korea's school system. Methods: Relevant literature and reports on SHP were investigated. On the basis of the analysis, this review closely examined how SHP had been developed, and what has been happening in the recent years of SHP in advanced nations. Results: Major findings from this review in terms of finding a new perspective on SHP in Korea were to: 1) share awareness of the fundamentals of SHP; 2) establish a national framework for school-based SHP; 3) build a cooperative SHP governance; 4) strengthen a SHP monitoring and evaluation system; 5) integrate health and education. Conclusion: Recently, serious student health threats have been putting pressure on schools in Korea. This review will serve as a critical implication of how to effectively implement SHP in Korea.

• Asian Pacific Journal of Cancer Prevention
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• 제17권8호
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• pp.4117-4123
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• 2016

Background: Methylation of promoter 2 of the SHP1 gene is epithelial cell specific, with reported potential as a lymph node metastatic marker. Objective: To demonstrate SHP1-P2 methylation-specific quantitative PCR effectiveness in detecting colorectal cancer (CRC) DNA in lymph nodes. Materials and Methods: SHP1-P2 methylation levels were measured in lymph nodes of CRC patients and compared with pathological findings and patient prognosis. Results: Lymph nodes of CRC metastatic patients without microscopically detectable cancer cells had higher SHP1-P2 methylation levels than lymph nodes of controls (p<0.001). In addition, a higher SHP1-P2 methylation level was associated with a shorter duration until adverse disease events, metastasis, recurrence and death (r2 = 0.236 and p value = 0.048). Studying two cohorts of 74 CRC patients without microscopic lymph node metastases showed that only the cohort containing samples with high SHP1-P2 methylation levels had a significant hazard ratio of 3.8 (95%CI = 1.02 to 14.2). Conclusions: SHP1-P2 methylation PCR can detect CRC DNA in lymph nodes even if cancer cells are not visible under a microscope, confirming applicability as a potential universal lymph node metastatic marker.

• 한국식품영양과학회지
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• 제37권9호
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• pp.1196-1201
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• 2008

함초 분말을 이용한 식빵의 품질에 대해 검토하였다. 함초분말 첨가에 의해 식빵의 조섬유, 칼슘 그리고 철분함량이 뚜렷하게 증가하였으며, pH는 함초 첨가 식빵이 대조구에 비해 높았다. 함초 분말을 0.6%에서 2.4%까지 첨가한 식빵의 염도는 대조구와 유의적인 차이를 나타내지 않았다. 함초분말 첨가 식빵의 표면 색도는 대조구에 비해 L값과 b값은 감소하였으나 a값은 증가하였고, 빵 내부의 색도는 함초 분말 첨가량 1.8%까지는 대조구와 유의적인 차이를 나타내지 않았다. 함초를 첨가한 식빵의 조직감(hardness, spinginess, chewiness, cohesiveness)은 대조구보다 높았으며, 함초 첨가량이 증가할수록 증가하였다. 식빵의 전자공여능을 조사한 결과, 함초 분말 0.6, 1.2 1.8, 2.4 및 6.0% 첨가구 각각 30.42, 33.91, 39.51, 41.17 및 63.82%로 대조구의 27.95%보다 높았으며, 함초 첨가량이 증가할수록 식빵의 지방산패 억제 활성은 증가하였고 폴리페놀 함량도 증가하였다.

• 태양에너지
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• 제20권2호
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• pp.67-73
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• 2000

This study represents the methodology of performance prediction for small hydro power(SHP) sites. Nine tunnel type SHP sites with diversion dam were selected and the performance characteristics were analyzed by using a developed model. Also, primary design specifications such as design flowrate, plant capacity, and operational rate were suggested and feasibility for tunnel-type SHP sites were estimated. It was found that the design flowrate was most important parameter to exploit SHP plant and the methodology developed in this study was useful tool to analyze the performance of SHP sites.

• IMMUNE NETWORK
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• 제2권2호
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• pp.72-78
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• 2002

Background: The precise mechanism by which CTLA-4 regulates T cell immune responses is still not fully understood. Previously we proposed that CTLA-4 could downregulate T cell function by modulating a signaling cascade initiated from the T cell receptor complex. The evidence for this notion comes from our findings that CTLA-4 associated with the T cell receptor zeta (TCR zeta) chain, and hence regulated TCR zeta phosphorylation by co-associated SHP-2 tyrosine phosphatase (1). In this report, we investigated whether any other signaling molecules could be involved in the CTLA-4 signaling pathway. Methods: We have taken biochemical approaches, such as immunoprecipitation followed by autoradiography or immunoblotting, to identify the molecules associated with CTLA-4. To perform these assays, we used activated primary T cells and ectopically transfected 293 cells. Various truncation mutants of CTLA-4 were used to map the interaction site on CTLA-4. Results: We found that in addition to TCR zeta and SHP-2, a recently cloned small adaptor molecule, SAP (SLAM-associated protein), was also able to associate with CTLA-4. We identified the domain of SAP association in CTLA-4 being a motif involving GVYVKM. This motif has been previously found to bind SHP-2 through its phosphorylated tyrosine interaction with SH-2 domain of SHP-2. Indeed, co-expression of SAP and SHP-2 reduced their binding to CTLA-4 significantly, suggesting that SAP and SHP-2 compete for the common binding site, GVYVKM. Thus, by blocking SHP-2 recruitment SAP could function as a negative regulator of CTLA-4. Conclusion: Taken together, our data suggest the existence of complicate signaling cascade in regulating CTLA-4 function, and further provide evidence that SAP can act either as a positive or negative regulator depending on the nature of the associating receptors.

• Molecules and Cells
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• 제23권3호
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• pp.331-339
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• 2007

It has been suggested that the structure and function of nuclear receptors are evolutionally conserved. Here, we compare the molecular functions of the nile tilapia (Oreochromis niloticus) small heterodimer partner (nSHP/NR0B2) and the Dosage-sensitive sex reversal AHC critical region on X chromosome gene 1 (nDAX-1/NR0B1) with those of human SHP and DAX-1 (hSHP and hDAX-1, respectively). We found that, upon transient cotransfection of human cells, nDAX-1 repressed the activity of tilapia SF-1 (nSF-1) but not that of human SF-1, although the physical interaction with human SF-1 was retained. Similarly, nSHP repressed the activity of nSF-1, whereas hSHP did not, pointing to divergent evolution of SHP/SF-1 in fish and human. We thus propose that the repressive functions of SHP and DAX-1 have been conserved in fish and mammals although with different transcriptional targets and mechanisms. These differences provide new insights into the physiological diversification of atypical orphan nuclear receptors during vertebrate evolution.