• 제목/요약/키워드: L-School

검색결과 10,016건 처리시간 0.042초

Characterization of Functional Domains in NME1L Regulation of NF-κB Signaling

  • You, Dong-Joo;Park, Cho Rong;Mander, Sunam;Ahn, Curie;Seong, Jae Young;Hwang, Jong-Ik
    • Molecules and Cells
    • /
    • 제39권5호
    • /
    • pp.403-409
    • /
    • 2016
  • NME1 is a well-known metastasis suppressor which has been reported to be downregulated in some highly aggressive cancer cells. Although most studies have focused on NME1, the NME1 gene also encodes the protein (NME1L) containing N-terminal 25 extra amino acids by alternative splicing. According to previous studies, NME1L has potent anti-metastatic activity, in comparison with NME1, by interacting with $IKK{\beta}$ and regulating its activity. In the present study, we tried to define the role of the N-terminal 25 amino acids of NME1L in $NF-{\kappa}B$ activation signaling. Unfortunately, the sequence itself did not interact with $IKK{\beta}$, suggesting that it may be not enough to constitute the functional structure. Further construction of NME1L fragments and biochemical analysis revealed that N-terminal 84 residues constitute minimal structure for homodimerization, $IKK{\beta}$ interaction and regulation of $NF-{\kappa}B$ signaling. The inhibitory effect of the fragment on cancer cell migration and $NF-{\kappa}B$-stimulated gene expression was equivalent to that of whole NME1L. The data suggest that the N-terminal 84 residues may be a core region for the anti-metastatic activity of NME1L. Based on this result, further structural analysis of the binding between NME1L and $IKK{\beta}$ may help in understanding the anti-metastatic activity of NME1L and provide direction to NME1L and $IKK{\beta}$-related anti-cancer drug design.

Structure and Photoreaction of Photoactive Yellow Protein

  • Imamoto, Yasushi;Harigai, Miki;Shimizu, Nobutaka;Kamikubo, Hironari;Yamazaki, Yoichi;Kataoka, Mikio
    • Journal of Photoscience
    • /
    • 제9권2호
    • /
    • pp.126-129
    • /
    • 2002
  • The chromophore/protein interactions in the photocycle intermediates of photoactive yel- low protein (PYP) were probed by site-directed mutagenesis. The absorption spectra of L- intermediates produced from E46Q, T50V, and R52Q mutants were calculated using the absorption spectra of dark states and difference absorption spectra between L-intermediates and dark states, and compared with that of PYP$\_$L/. The absorption spectrum of R52Q$\_$L/ agreed with that of PYP$\_$L/, but those of E46Q$\_$L/ and T50V$\_$L/ were red-shifted. The effect of these mutations on the absorption spectrum for L-intermediate was comparable to that for the dark state, suggesting that the interaction around the phe-nolic oxygen of the chromophore is conserved in PYP$\_$L/ unlike the crystal structure. On the other hand, we have reported that the absorption spectra of Y 42F$\_$M/, T50V $\_$M/, and R52Q$\_$M/ agreed with that of PYP$\_$M/, but that of E46Q$\_$M/ was red-shifted, suggesting that the hydrogen bond of the chromophore with Glu46 is conserved but that with Tyr42 is broken in PYP$\_$M/. These results suggest that the chromophore inter-acts with Glu46 throughout the photocycle, but never directly interacts with Arg52. This model con- flicts with some of the structural model of PYP intermediates proposed based on the high-resolution X -ray crystallography.

  • PDF

Histone Deacetylase Inhibitors Induce the Differentiation of Eosinophilic Leukemia EoL-1 Cells into Eosinophils

  • Ishihara Kenji;Hong Jang-Ja;Kaneko Motoko;Takahashi Aki;Sugeno Hiroki;Kang Young-Sook;Ohuchi Kazuo
    • Biomolecules & Therapeutics
    • /
    • 제14권2호
    • /
    • pp.67-74
    • /
    • 2006
  • EoL-1 cells differentiate into eosinophils in the presence of n-butyrate, but the mechanism has remained to be elucidated. Because n-butyrate can inhibit histone deacetylases, we hypothesized that the inhibition of histone deacetylases induces the differentiation of EoL-1 cells into eosinophils. In this study, using n-butyrate and two other histone deacetylase inhibitors, apicidin and trichostatin A, we have analyzed the relationship between the inhibition of histone deacetylases and the differentiation into eosinophils in EoL-1 cells. It was demonstrated that apicidin and n-butyrate induced a continuous acetylation of histones H4 and H3, inhibited the proliferation of EoL-1 cells, and induced the expression of markers for mature eosinophils such as integrin ${\beta}7$, CCR1, and CCR3 on EoL-1 cells, while trichostatin A evoked a transient acetylation of his tones and induced no differentiation into eosinophils. These findings suggest that the continuous inhibition of histone deacetylases in EoL-1 cells induces the differentiation into mature eosinophils.

LIST EDGE AND LIST TOTAL COLORINGS OF PLANAR GRAPHS WITHOUT 6-CYCLES WITH CHORD

  • Dong, Aijun;Liu, Guizhen;Li, Guojun
    • 대한수학회보
    • /
    • 제49권2호
    • /
    • pp.359-365
    • /
    • 2012
  • Giving a planar graph G, let $x^'_l(G)$ and $x^{''}_l(G)$ denote the list edge chromatic number and list total chromatic number of G respectively. It is proved that if a planar graph G without 6-cycles with chord, then $x^'_l(G){\leq}{\Delta}(G)+1$ and $x^{''}_l(G){\leq}{\Delta}(G)+2$ where ${\Delta}(G){\geq}6$.

Detailed Mode of Action of Arabinan-Debranching α-ʟ-Arabinofuranosidase GH51 from Bacillus velezensis

  • Oh, Gyo Won;Kang, Yewon;Choi, Chang-Yun;Kang, So-Yeong;Kang, Jung-Hyun;Lee, Min-Jae;Han, Nam Soo;Kim, Tae-Jip
    • Journal of Microbiology and Biotechnology
    • /
    • 제29권1호
    • /
    • pp.37-43
    • /
    • 2019
  • The gene encoding an ${\alpha}-{\text\tiny{L}}-arabinofuranosidase$ (BvAF) GH51 from Bacillus velezensis FZB42 was cloned and expressed in Escherichia coli. The corresponding open reading frame consists of 1,491 nucleotides which encode 496 amino acids with the molecular mass of 56.9 kDa. BvAF showed the highest activity against sugar beet (branched) arabinan in 50 mM sodium acetate buffer (pH 6.0) at $45^{\circ}C$. However, it could hardly hydrolyze debranched arabinan and arabinoxylans. The time-course hydrolyses of branched arabinan and arabinooligosaccharides (AOS) revealed that BvAF is a unique exo-hydrolase producing exclusively ${\text\tiny{L}}-arabinose$. BvAF could cleave ${\alpha}-(1,2)-$ and/or ${\alpha}-(1,3)-{\text\tiny{L}}-arabinofuranosidic$ linkages of the branched substrates to produce the debranched forms of arabinan and AOS. Although the excessive amount of BvAF could liberate ${\text\tiny{L}}-arabinose$ from linear AOS, it was extremely lower than that on branched AOS. In conclusion, BvAF is the arabinan-specific exo-acting ${\alpha}-{\text\tiny{L}}-arabinofuranosidase$ possessing high debranching activity towards ${\alpha}-(1,2)-$ and/or ${\alpha}-(1,3)-linked$ branches of arabinan, which can facilitate the successive degradation of arabinan by $endo-{\alpha}-(1,5)-{\text\tiny{L}}-arabinanase$.

Morphometric Analysis of the Ureter with Respect to Lateral Lumbar Interbody Fusion Using Contrast-Enhanced Computed Tomography

  • Chunneng Huang;Zhenyu Bian;Liulong Zhu
    • Journal of Korean Neurosurgical Society
    • /
    • 제66권2호
    • /
    • pp.155-161
    • /
    • 2023
  • Objective : To analyze the anatomical location of the ureter in relation to lateral lumbar interbody fusion and evaluate the potential risk of ureteral injury. Methods : One hundred eight patients who performed contrast-enhanced computed tomographic scans were enrolled in this study. The location of the ureter from L2-L3 to L4-L5 was evaluated. The distances between the ureter and psoas muscle, intervertebral disc, and retroperitoneal vessels were also recorded bilaterally. Results : Over 30% of the ureters were close to the working corridor of extreme lumbar interbody fusion at L2-L3. Most of the ureters were close to working corridor of oblique lumbar interbody fusion, especially at L4-L5. The distance from the ureter to the great vessels on the left side was significantly narrowing from L2-L3 to L4-L5 (28.8±9.5 mm, 22.0±8.0 mm, 15.5±8.4 mm), and it was significantly larger than that on the right side (12.3±6.1 mm, 7.4±5.7 mm, 5.4±4.4 mm). Conclusion : Our findings indicate that the location of the ureter varies widely among individuals. To avoid unexpected damage to the ureter, it is imperative to directly visualize it and verify the ureter is not in the surgical pathway during lateral lumbar interbody fusion.

Preventable effect of L-threonate, an ascorbate metabolite, on androgen-driven balding via repression of dihydrotestosteroneinduced dickkopf-1 expression in human hair dermal papilla cells

  • Kwack, Mi-Hee;Ahn, Ji-Sup;Kim, Moon-Kyu;Kim, Jung-Chul;Sung, Young-Kwan
    • BMB Reports
    • /
    • 제43권10호
    • /
    • pp.688-692
    • /
    • 2010
  • In a previous study, we recently claimed that dihydrotestosterone (DHT)-inducible dickkopf-1 (DKK-1) expression is one of the key factors involved in androgen-potentiated balding. We also demonstrated that L-ascorbic acid 2-phosphate (Asc 2-P) represses DHT-induced DKK-1 expression in cultured dermal papilla cells (DPCs). Here, we investigated whether or not L-threonate could attenuate DHT-induced DKK-1 expression. We observed via RT-PCR analysis and enzyme-linked immunosorbent assay that DHT-induced DKK-1 expression was attenuated in the presence of L-threonate. We also found that DHT-induced activation of DKK-1 promoter activity was significantly repressed by L-threonate. Moreover, a co-culture system featuring outer root sheath (ORS) keratinocytes and DPCs showed that DHT inhibited the growth of ORS cells, which was then significantly reversed by L-threonate. Collectively, these results indicate that L-threonate inhibited DKK-1 expression in DPCs and therefore is a good treatment for the prevention of androgen-driven balding.

파라미터에 종속적인 리아푸노프 함수 기법에 의한 불확실 시간지연 시스템을 위한 강인한 $L_2-L_{\infty}$ 필터 설계 (Robust $L_2-L_{\infty}$ Filter Design for Uncertain Time-Delay Systems via a Parameter-Dependent Lyapunov Function Approach)

  • 최현철;정진우;심형보;서진헌
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2008년도 학술대회 논문집 정보 및 제어부문
    • /
    • pp.177-178
    • /
    • 2008
  • An LMI-based method for robust $L_2-L_{\infty}$ filter design is proposed for poly topic uncertain time-delay systems. By using the Projection Lemma and a suitable linearizing transformation, a strict LMI condition for $L_2-L_{\infty}$ filter design is obtained, which does not involve any iterations for design-parameter search, any couplings between the Lyapunov and system matrices, nor any system-dependent filter parameterization. Therefore, the proposed condition enables one to easily adopt, with help of efficient numerical solvers, a parameter-dependent Lyapunov function approach for reducing conservatism, and to design both robust and parameter-dependent filters for uncertain and parameter-dependent time-delay systems, respectively.

  • PDF