• BMB Reports
• /
• 제54권12호
• /
• pp.626-631
• /
• 2021

Janus kinase 2 (JAK2), a non-receptor tyrosine kinase, is a critical component of cytokine and growth factor signaling pathways regulating hematopoietic cell proliferation. JAK2 mutations are associated with multiple myeloproliferative neoplasms. Although physiological and pathological functions of JAK2 in hematopoietic tissues are well-known, such functions of JAK2 in the nervous system are not well studied yet. The present study demonstrated that JAK2 could negatively regulate neuronal differentiation of mouse embryonic stem cells (ESCs). Depletion of JAK2 stimulated neuronal differentiation of mouse ESCs and activated glycogen synthase kinase 3β, Fyn, and cyclin-dependent kinase 5. Knockdown of JAK2 resulted in accumulation of GTP-bound Rac1, a Rho GTPase implicated in the regulation of cytoskeletal dynamics. These findings suggest that JAK2 might negatively regulate neuronal differentiation by suppressing the GSK-3β/Fyn/CDK5 signaling pathway responsible for morphological maturation.

• Journal of Ginseng Research
• /
• 제42권4호
• /
• pp.436-446
• /
• 2018

Background: The potential therapeutic values of Korean Red Ginseng extract (KRGE) in autoimmune disorders of nervous system have not been fully investigated. Methods: We used an acute experimental autoimmune encephalomyelitis animal model of multiple sclerosis and determined the effects and mechanism of KRGE on spinal myelination. Results: Pretreatment with KRGE (100 mg/kg, orally) for 10 days before immunization with myelin basic protein $(MBP)_{68-82}$ peptide exerted a protective effect against demyelination in the spinal cord, with inhibited recruitment and activation of immune cells including microglia, decreased mRNA expression of detrimental inflammatory mediators (interleukin-6, interferon-${\gamma}$, and cyclooxygenase-2), but increased mRNA expression of protective inflammatory mediators (insulin-like growth factor ${\beta}1$, transforming growth factor ${\beta}$, and vascular endothelial growth factor-1). These results were associated with significant downregulation of p38 mitogen-activated protein kinase and nuclear factor-${\kappa}B$ signaling pathways in microglia/macrophages, T cells, and astrocytes. Conclusion: Our findings suggest that KRGE alleviates spinal demyelination in acute experimental autoimmune encephalomyelitis through inhibiting the activation of the p38 mitogen-activated protein kinase/nuclear factor-${\kappa}B$ signaling pathway. Therefore, KRGE might be used as a new therapeutic for autoimmune disorders such as multiple sclerosis, although further investigation is needed.

• 통합자연과학논문집
• /
• 제10권2호
• /
• pp.95-104
• /
• 2017

Proviral Integration site of Moloney (Pim) murine Leukemia virus kinases is a serine/threonine specific protein kinase. It is largely involved in cell survival and proliferation. Pim-1 phosphorylates multiple cellular substrates to inhibit apoptosis and promote cell cycle progression. Over expression of Pim-1 kinase is observed in a range of malignancies and various solid cancers. High level of Pim-1 expression is seen in myeloma, acute myeloid leukemia, prostate cancer and liver carcinomas. Hence, Pim-1 is considered as an interesting cancer target. In the present study, we have performed region-focused CoMFA study on a series of imidazopyridazine derivatives as Pim-1 kinase inhibitors. A statistically acceptable region-focused CoMFA model ($q^2=0.571$; ONC=3; $r^2=0.909$) was developed. The model was then validated using Bootsrapping and progressive sampling. The contour map highlighted the regions favorable to increase the activity. Bulky substitutions in $R^2$ position of the phenyl ring could increase the activity. Similarly, small negative substitution in the $R^1$ position of the Pyridine ring could increase the activity considerably. Our results will be useful to design novel Pim-1 kinase inhibitors of this series.

• 한국발생생물학회지:발생과생식
• /
• 제18권1호
• /
• pp.65-71
• /
• 2014

Cell cycle process is regulated by a number of protein kinases and among them, serine/threonine kinases carry phosphate group from ATP to substrates. The most important three kinase families are Cyclin-dependent kinase (Cdk), Polo-like kinase (Plk), and Aurora kinase. Polo-like kinase family consists of 5 members (Plk1-Plk5) and they are involved in multiple functions in eukaryotic cell division. It regulates a variety of aspects such as, centrosome maturation, checkpoint recovery, spindle assembly, cytokinesis, apoptosis and many other features. Recently, it has been reported that Plks are related to tumor development and over-expressed in many kinds of tumor cells. When injected the anti-Plk antibody into human cells, the cells show aneuploidy, and if inhibit Plks, most of the mitotic cell division does not proceed properly. For that reasons, many inhibitors of Plk have been recently emerged as new target for remedy of the cancer therapeutic research. In this paper, we reviewed briefly the characteristics of Plk families and how Plks work in regulating cell cycles and cancer formation, and the possibilities of Plks as target for cancer therapy.

• Journal of Plant Biotechnology
• /
• 제42권1호
• /
• pp.1-5
• /
• 2015

The biological roles of glycogen synthase kinase 3 (GSK3) proteins have long been extensively explored in eukaryotic organisms including fungi, animals and plants. This gene family has evolutionary well conserved kinase domain and shares similar phosphorylation properties to their substrate proteins. However, their specific biological roles are surprisingly distinct in different organisms. GSK3s play key role in key regulating the cytoskeleton and metabolic processes in animal systems, but plant GSKs are involved in quite different processes, such as flower development, brassinosteroid signaling, abiotic stresses, and organogenesis. In particular, recent studies have reported the critical multiple functions of BIN2 and its related paralogues plant GSK3s during organogenesis via connecting hormonal or developmental programs. In this review, we outline the recent understanding in the versatile functions related in physiological and biochemical relevance, which are mediated by plant GSK3s in various cellular signaling.

• Journal of Applied Biological Chemistry
• /
• 제48권3호
• /
• pp.120-126
• /
• 2005

Endothelial nitric oxide synthase (eNOS) plays a critical role in vascular biology and pathophysiology. Its activity is regulated by multiple mechanisms such as calcium/calmodulin, protein-protein interactions, sub-cellular locations and phosphorylation at various sites. Phosphorylation of eNOS-Ser1177 (based on mouse sequence) has been identified as an important mechanism of eNOS activation. However, signaling pathway leading to it phosphorylation remains controversial. The regulation of eNOS-Ser1177 phosphorylation by Src and protein kinase A (PKA) was investigated in the present study using cultured mouse aorta endothelial cells. Expression of a constitutively active Src mutant in the cells enhanced phosphorylation of eNOS and protein kinase B (Akt). The Src-stimulated phosphorylation was not attenuated by the expression of a dominant negative PKA regulatory subunit. Neither activation nor inhibition of PKA activity had any significant effect on tyrosine phosphorylation of activation or inactivation site in Src. Based on the results of this study, it is suggested that Src/Akt pathway and PKA signaling may regulate eNOS phosphorylation independently. The existence of multiple mechanisms for eNOS phosphorylation may guarantee endothelial nitric oxide production in various cellular contexts which is essential for maintenance of vascular health.

• Animal cells and systems
• /
• 제14권3호
• /
• pp.155-160
• /
• 2010

Extracellular signal-regulated kinases 1/2 (ERK1/2) play important roles in a variety of biological processes including cell growth and differentiation. We have previously reported that GAR-3 activates ERK1/2 via phospholipase C and protein kinase C, presumably through pertussis toxin (PTX)-insensitive Gq proteins, in Chinese hamster ovary (CHO) cells. Here we provide evidence that GAR-3 also activates ERK1/2 through PTX-sensitive G proteins, phosphatidylinositol 3-kinase (PI 3-kinase), and Src family kinases in CHO cells. We further show that in human embryonic kidney (HEK293) cells, epidermal growth factor receptor and Ras are required for efficient ERK1/2 activation by GAR-3. Taken together, our data indicate that GAR-3 evokes ERK1/2 activation through multiple signaling pathways in cultured mammalian cells.

• Bulletin of the Korean Chemical Society
• /
• 제33권5호
• /
• pp.1571-1576
• /
• 2012

A diarylurea compound 1 possessing pyrrolo[3,2-$c$]pyridine nucleus was designed and synthesized with structure similarity to Sorafenib. Compound 1 was tested over 60-cancer cell line panel at a single dose concentration of 10 ${\mu}M$ and showed high activity. It was further tested in a five-dose mode to determine its $IC_{50}$, TGI, and $LC_{50}$ values over the 60 cell lines. Compound 1 showed high potency and good efficacy, and was accordingly tested at a single dose concentration of 10 ${\mu}M$ over a panel of 40 kinases. At this concentration, it completely inhibited the enzymatic activities of a number of oncogenic kinases, including ABL, ALK, c-RAF, FLT3, KDR, and TrkB. The target compound was subsequently tested over these 6 kinases in 10-dose testing mode in order to determine its $IC_{50}$ values.

• 한국패류학회지
• /
• 제29권3호
• /
• pp.171-179
• /
• 2013

동양달팽이의 arginine kinase 유전자는 염기서열 1065개로 이루어져있으며 355개의 아미노산으로 이루어져 있으며, BLAST 결과를 토대로 유사도가 높은 25개의 참고 서열과 동양달팽이의 arginine kinase의 아미노산 서열을 MEGA5 프로그램의 clustalW 모듈을 이용하여 multiple sequence alignment 를 수행한 결과, 연체동물문에 속하는 복족강 (5종), 두족강 (5종), 이매패강 (4종) 등에 속하는 생물들이 같은 군으로 묶였으며, 절지동물문 곤충강 에 속하는 나비목 (2종), 벌목 (1종), 노린재목 (2종) 등에 속하는 생물들이 같은 군으로 묶이고, 갑각강 (5종), 거미강 (1종) 에 속하는 생물들이 묶이는 것을 알 수 있었다. Psipred 소프트웨어를 통해 2D 구조를 비교 분석한 결과도 multiple align 및 phylodendrogram 결과와 밀접한 관계가 있음을 알 수 있었다. 시간에 따른 arginine kinase의 발현양상을 확인한 결과 control에 비하여 6시간에서 약 1.2배 정도 발현이 증가하는 것을 확인할 수 있었으며, 12시간이 지나면 점차 감소하는 것을 확인할 수 있었다. EST를 통해 밝혀진 N. samarangae 의 Ark 서열은 근연종들의 서열과 일치함을 알 수 있었으며, 본 연구 결과를 통해 무척추동물에서의 선천성 면역 관련 유전자 연구에 동양달팽이가 좋은 모델이 될 수 있음을 제시하고 있다.

• Asian Pacific Journal of Cancer Prevention
• /
• 제14권5호
• /
• pp.2699-2701
• /
• 2013

The RAS family genes encode small GTP-binding cytoplasmic proteins. Activated KRAS engages multiple effector pathways, notably the RAF-mitogen-activated protein kinase, phosphoinositide-3-kinase (PI3K) and RalGDS pathways. In the clinical field, K-ras oncogene activation is frequently found in human cancers and thus may serve as a potential diagnostic marker for cancer cells in circulation. This mini-review aims to summarise information on Ras-induced oncogenesis and the clinical significance of K-ras.