• Title/Summary/Keyword: noncanonical

Search Result 11, Processing Time 0.019 seconds

Characterization of a Noncanonical Purine dNTP Pyrophosphatase from Archaeoglobus fulgidus

  • Im Eun-Kyoung;Hong Chang-Hyung;Back Jung-Ho;Han Ye-Sun;Chung Ji-Hyung
    • Journal of Microbiology and Biotechnology
    • /
    • v.16 no.7
    • /
    • pp.1144-1148
    • /
    • 2006
  • DNA can oxidatively be deaminated by ROS, which converts DNA base amino groups to keto groups and can trigger abnormal mutations, resulting in mutagenesis in organisms. In this study, a noncanonical purine dNTP pyrophosphatase (AfPPase) from a hyperthermophilic archaeon Archaeoglobus fulgidus, which hydrolyzes aberrant nucleoside triphosphates, was overexpressed in E. coli, purified, and characterized. The purified AfPPase showed remarkably high activity for XTP and dITP, suggesting that the 6-keto group of these nucleotides is critical for the reactivity. Under optimal reaction conditions, the reaction rate for these substrates was about 120 times that with dGTP. Therefore, AfPPase may play a significant role in DNA repair by hydrolysis of noncanonical nucleotides before they are misincorporated into DNA.

4-O-Methylhonokiol Protects HaCaT Cells from TGF-β1-Induced Cell Cycle Arrest by Regulating Canonical and Non-Canonical Pathways of TGF-β Signaling

  • Kim, Sang-Cheol;Kang, Jung-Il;Hyun, Jin-Won;Kang, Ji-Hoon;Koh, Young-Sang;Kim, Young-Heui;Kim, Ki-Ho;Ko, Ji-Hee;Yoo, Eun-Sook;Kang, Hee-Kyoung
    • Biomolecules & Therapeutics
    • /
    • v.25 no.4
    • /
    • pp.417-426
    • /
    • 2017
  • 4-O-methylhonokiol, a neolignan compound from Magnolia Officinalis, has been reported to have various biological activities including hair growth promoting effect. However, although transforming growth factor-${\beta}$ (TGF-${\beta}$) signal pathway has an essential role in the regression induction of hair growth, the effect of 4-O-methylhonokiol on the TGF-${\beta}$ signal pathway has not yet been elucidated. We thus examined the effect of 4-O-methylhonokiol on TGF-${\beta}$-induced canonical and noncanonical pathways in HaCaT human keratinocytes. When HaCaT cells were pretreated with 4-O-methylhonokiol, TGF-${\beta}1$-induced G1/G0 phase arrest and TGF-${\beta}1$-induced p21 expression were decreased. Moreover, 4-O-methylhonokiol inhibited nuclear translocation of Smad2/3, Smad4 and Sp1 in TGF-${\beta}1$-induced canonical pathway. We observed that ERK phosphorylation by TGF-${\beta}1$ was significantly attenuated by treatment with 4-O-methylhonokiol. 4-O-methylhonokiol inhibited TGF-${\beta}1$-induced reactive oxygen species (ROS) production and reduced the increase of NADPH oxidase 4 (NOX4) mRNA level in TGF-${\beta}1$-induced noncanonical pathway. These results indicate that 4-O-methylhonokiol could inhibit TGF-${\beta}1$-induced cell cycle arrest through inhibition of canonical and noncanonical pathways in human keratinocyte HaCaT cell and that 4-O-methylhonokiol might have protective action on TGF-${\beta}1$-induced cell cycle arrest.

Regulation of mitochondrial morphology and metabolism by Jak-STAT pathway

  • Rhee, Kun Do
    • Journal of Animal Reproduction and Biotechnology
    • /
    • v.36 no.4
    • /
    • pp.189-193
    • /
    • 2021
  • Jak-STAT pathway is required for embryogenesis, female gametogenesis, cytokine-mediated neuroprotection, diabetes, obesity, cancer, stem cell, and various tissues. The noncanonical role of Jak-STAT in mitochondria function was supported by the detection of STAT protein in mitochondria, however, several studies show that STAT protein is detected in the endoplasmic reticulum (ER), and not in mitochondria. STAT protein may alter mitochondria function without entering mitochondria, this involves regulation of fission and fusion proteins to change mitochondria morphology. However, how changes in mitochondria morphology lead to changes in mitochondria metabolism needs further investigation.

Phosphoserine Phosphatase Promotes Lung Cancer Progression through the Dephosphorylation of IRS-1 and a Noncanonical L-Serine-Independent Pathway

  • Park, Seong-Min;Seo, Eun-Hye;Bae, Dong-Hyuck;Kim, Sung Soo;Kim, Jina;Lin, Weiwei;Kim, Kyung-Hee;Park, Jong Bae;Kim, Yong Sung;Yin, Jinlong;Kim, Seon-Young
    • Molecules and Cells
    • /
    • v.42 no.8
    • /
    • pp.604-616
    • /
    • 2019
  • Phosphoserine phosphatase (PSPH) is one of the key enzymes of the L-serine synthesis pathway. PSPH is reported to affect the progression and survival of several cancers in an L-serine synthesis-independent manner, but the mechanism remains elusive. We demonstrate that PSPH promotes lung cancer progression through a noncanonical L-serine-independent pathway. PSPH was significantly associated with the prognosis of lung cancer patients and regulated the invasion and colony formation of lung cancer cells. Interestingly, L-serine had no effect on the altered invasion and colony formation by PSPH. Upon measuring the phosphatase activity of PSPH on a serine-phosphorylated peptide, we found that PSPH dephosphorylated phospho-serine in peptide sequences. To identify the target proteins of PSPH, we analyzed the protein phosphorylation profile and the PSPH-interacting protein profile using proteomic analyses and found one putative target protein, IRS-1. Immunoprecipitation and immunoblot assays validated a specific interaction between PSPH and IRS-1 and the dephosphorylation of phospho-IRS-1 by PSPH in lung cancer cells. We suggest that the specific interaction and dephosphorylation activity of PSPH have novel therapeutic potential for lung cancer treatment, while the metabolic activity of PSPH, as a therapeutic target, is controversial.

Rules for functional microRNA targeting

  • Kim, Doyeon;Chang, Hee Ryung;Baek, Daehyun
    • BMB Reports
    • /
    • v.50 no.11
    • /
    • pp.554-559
    • /
    • 2017
  • MicroRNAs (miRNAs) are ~22nt-long single-stranded RNA molecules that form a RNA-induced silencing complex with Argonaute (AGO) protein to post-transcriptionally downregulate their target messenger RNAs (mRNAs). To understand the regulatory mechanisms of miRNA, discovering the underlying functional rules for how miRNAs recognize and repress their target mRNAs is of utmost importance. To determine functional miRNA targeting rules, previous studies extensively utilized various methods including high-throughput biochemical assays and bioinformatics analyses. However, targeting rules reported in one study often fail to be reproduced in other studies and therefore the general rules for functional miRNA targeting remain elusive. In this review, we evaluate previously-reported miRNA targeting rules and discuss the biological impact of the functional miRNAs on gene-regulatory networks as well as the future direction of miRNA targeting research.

A Study on Anti-Design and Italian Radical Fashion (안티디자인과 이탈리아 급진주의 패션에 관한 연구)

  • 이현미
    • The Research Journal of the Costume Culture
    • /
    • v.9 no.1
    • /
    • pp.154-168
    • /
    • 2001
  • This study is intended to understand an implication and significant of anti-design and Italian radical fashion. Anti-design and radicalism is the main stream or origin and essence of post-modernism which hs been swaying our society at large through modern culture, economy, art, fashion etc, from the latter part of 1960s. In this paper, the author classified the italian radical fashion with the Archizoom, the Alchymia, the memphis fashion. In post-modernism fashion, radical fashion design of the Archizoom, Alchymia and Memphis group is in part a menifesto and in part a noncanonical history of the most progressive and heretical experiments of the world of fashion. Anti-designers of Italy call for a theory an practive in which the old methods and instruments and the old commendments of modernism are banished. They looked on fashion as material culture, a creative field with its own independent foundation and endowed with its own strong artistic intuition. IF radical design is dead, the energy it has stirred up is still alive nd kicking. One of the most progressive and well-informed culture milieus in Milian, seved as a point of reference for the vanguard of fashion.

  • PDF

Midline enhancer activity of the short gastrulation shadow enhancer is characterized by three unusual features for cis-regulatory DNA

  • Shin, Dong-Hyeon;Hong, Joung-Woo
    • BMB Reports
    • /
    • v.48 no.10
    • /
    • pp.589-594
    • /
    • 2015
  • The shadow enhancer of the short gastrulation (sog) gene directs its sequential expression in the neurogenic ectoderm and the ventral midline of the developing Drosophila embryo. Here, we characterize three unusual features of the shadow enhancer midline activity. First, the minimal regions for the two different enhancer activities exhibit high overlap within the shadow enhancer, meaning that one developmental enhancer possesses dual enhancer activities. Second, the midline enhancer activity relies on five Single-minded (Sim)-binding sites, two of which have not been found in any Sim target enhancers. Finally, two linked Dorsal (Dl)- and Zelda (Zld)-binding sites, critical for the neurogenic ectoderm enhancer activity, are also required for the midline enhancer activity. These results suggest that early activation by Dl and Zld may facilitate late activation via the noncanonical sites occupied by Sim. We discuss a model for Zld as a pioneer factor and speculate its role in midline enhancer activity.

How Z-DNA/RNA binding proteins shape homeostasis, inflammation, and immunity

  • Kim, Chun
    • BMB Reports
    • /
    • v.53 no.9
    • /
    • pp.453-457
    • /
    • 2020
  • The right-handed double-helical structure of DNA (B-DNA), which follows the Watson-Crick model, is the canonical form of DNA existing in normal physiological settings. Even though an alternative left-handed structure of DNA (Z-DNA) was discovered in the late 1970s, Z-form nucleic acid has not received much attention from biologists, because it is extremely unstable under physiological conditions, has an ill-defined mechanism of its formation, and has obscure biological functions. The debate about the physiological relevance of Z-DNA was settled only after a class of proteins was found to potentially recognize the Z-form architecture of DNA. Interestingly, these Z-DNA binding proteins can bind not only the left-handed form of DNA but also the equivalent structure of RNA (Z-RNA). The Z-DNA/RNA binding proteins present from viruses to humans function as important regulators of biological processes. In particular, the proteins ADAR1 and ZBP1 are currently being extensively re-evaluated in the field to understand potential roles of the noncanonical Z-conformation of nucleic acids in host immune responses and human disease. Despite a growing body of evidence supporting the biological importance of Z-DNA/RNA, there remain many unanswered principal questions, such as when Z-form nucleic acids arise and how they signal to downstream pathways. Understanding Z-DNA/RNA and the sensors in different pathophysiological conditions will widen our view on the regulation of immune responses and open a new door of opportunity to develop novel types of immunomodulatory therapeutic possibilities.

Enhanced Expression of ${\beta}-Xylosidase$ of Bacillus stearothemophilus No. 236 by Change of Translational Initiation Codon in Escherichia coli and Bacillus subtilis

  • Kim, Mi-Dong;Kim, Kyung-Nam;Choi, Yong-Jin
    • Journal of Microbiology and Biotechnology
    • /
    • v.13 no.4
    • /
    • pp.584-590
    • /
    • 2003
  • The xylA gene of Bacillus stearothermophilus No. 236 encoding ${\beta}-xylosidase$, a major xylanolytic enzyme, was previously cloned and sequenced by the present authors. Sequence analysis indicated that translation of the xylA gene was initiated from the noncanonical initiation codon UUG, confirmed by analyzing three different amber (UAG) mutants of the xylA gene. In the present study, the UUG initiation codon was mutated into AUG or GUG, and the effects of the mutations on the XylA synthesis were examined. The AUG initiation codon was found to direct the highest level of ${\beta}-xylosidase$ synthesis; three-fold and fourteen-fold more enzyme activity than the UUG codon in E. coli and B. subtilis cells, respectively. Surprisingly, contrary to other systems reported to date, the UUG start codon was found next to AUG in the relative order of translational efficiency in both organisms. In addition, a greater abundance of the xylA mRNA was detected with the AUG start codon in both of these host cells than with GUG or UUG. Northern blot and Toeprint assays revealed that this was due to enhanced stability of mRNA with the AUG initiation codon. As expected, the ${\beta}-xylosidase$ protein level in the bacterial cells containing mRNA with the AUC start codon was also much higher than the levels with the other two different mRNAs.

Functional Analysis of Fibroblastic Reticular Cells Derived from Mouse Lymph Node via Bidirectional Crosstalk with T Cells (T세포와 양방향 작용을 통한 마우스 림프절로부터 분리된 fibroblastic reticular cell의 기능적 분석)

  • Park, Sung Hee;Lee, Jong-Hwan
    • Journal of Life Science
    • /
    • v.23 no.10
    • /
    • pp.1199-1208
    • /
    • 2013
  • Fibroblastic reticular cells (FRCs) form the structural backbone of the T zone provide a guidance path for immigrating T cells in the lymph node (LN). FRCs may contribute directly to developing T-cell biology in the LN and allow analyses of fundamental aspects of FRC biology related to T cells. FRCs inhibited T-cell apoptosis, and FRC culture supernatants strongly induced the expression of Bcl-xL in T cells against doxorubicin. Coculture of FRC and T cells resulted in rearrangements of the actin cytoskeleton, as well as global changes in the morphology of the FRCs. In addition, when cocultured, the T cells adhered to the FRC monolayer, and the membrane intercellular adhesion molecule (ICAM)-1 was slightly increased by day-dependent manner. In contrast, the expression of soluble ICAM-1 was dramatically increased in a day-dependent manner. Several chemokines, such as CCL5, CXCL1, CXCL5, CXCL16, CCL8, CXCL13, and ICAM-1, and MMPs were expressed in FRCs sensed by tumor necrosis factor (TNF) families. Nuclear factor kappa B ($NF{\kappa}B$)-RelA of the $NF{\kappa}B$ canonical pathway was translocated into FRC nuclear by $TNF{\alpha}$. In contrast, p52 proteolyzed from p100, a counterpart of RelB of the noncanonical $NF{\kappa}B$ pathway, accumulated in the peripheral FRC nucleus by agonistic anti-$LT{\beta}R$ antibody. In summary, we propose a model in which FRCs engage in bidirectional crosstalk to increase the efficiency of T-cell biology. This cooperative feedback loop may help to maintain tissue integrity and function during immune responses.