• Biomolecules & Therapeutics
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• v.32 no.6
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• pp.767-777
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• 2024

The deregulation of protein translational machinery and the oncogenic role of several translation initiation factors have been extensively investigated. This study aimed to investigate the role of eukaryotic translation initiation factor 2S2 (eIF2S2, also known as eIF2β) in cervical carcinogenesis. Immunohistochemical analysis of human cervical carcinoma tissues revealed a stage-specific increase in eIF2S2 expression. The knockdown of eIF2S2 in human cervical cancer (SiHa) cells significantly reduced growth and migration properties, whereas its overexpression demonstrated the opposite effect. Immunoprecipitation and Bimolecular fluorescence complementation (BiFC) assay confirmed the previous photo array finding of the interaction between eIF2S2 and SMAD4 to understand the tumorigenic mechanism of eIF2S2. The results indicated that the N-terminus of eIF2S2 interacts with the MH-1 domain of SMAD4. The interaction effect between eIF2S2 and SMAD4 was further evaluated. The knockdown of eIF2S2 increased SMAD4 expression in cervical cancer cells without changing SMAD4 mRNA expression, whereas transient eIF2S2 overexpression reduced SMAD4 expression. This indicates the possibility of post-translational regulation of SMAD4 expression by eIF2S2. Additionally, eIF2S2 overexpression was confirmed to weaken the expression and/or promoter activity of p15 and p27, which are SMAD4-regulated antiproliferative proteins, by reducing SMAD4 levels. Therefore, our study indicated the pro-tumorigenic role of eIF2S2, which diminishes both SMAD4 expression and function as a transcriptional factor in cervical carcinogenesis.

• Journal of Life Science
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• v.23 no.7
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• pp.941-946
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• 2013

Local protein synthesis at subsynaptic sites plays a key role in the regulation of the protein composition in local domains. In this study, we carried out immunocytochemistry of cultured rat hippocampal neurons in various developmental stages to investigate the expression of eIF4E and its binding protein, eIF4EBP1. Both proteins were distributed in dendrites. In addition, eIF4EBP1 was highly expressed in the nucleus throughout the development, whereas eIF4E was not expressed in the nucleus. Punctate expression of eIF4E and eIF4EBP1 was evident in DIV 3. The colocalization rates of eIF4E or eIF4EBP1 puncta with PSD95 were higher in the dendrogenic than in the mature stages. In contrast, the colocalization rates of eIF4E and eIF4EBP1 puncta were higher in the mature than in the dendrogenic stages. As eIF4E is inactive when it is bound to eIF4EBP1, these data indicate that most dendritic eIF4E's are active during development but that they are mostly under inhibition in mature neurons.

• Journal of the Korean Mathematical Society
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• v.59 no.1
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• pp.71-85
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• 2022

In [4], the authors showed that if an h-vector (h₀, h₁, …, h_e) with h₁ = 4e - 4 and h_i ≤ h₁ is a Gorenstein sequence, then h₁ = h_i for every 1 ≤ i ≤ e - 1 and e ≥ 6. In th_is paper, we show that if an h-vector (h₀, h₁, …, h_e) with h₁ = 4e - 4, h₂ = 4e - 3, and h_i ≤ h₂ is a Gorenstein sequence, then h₂ = h_i for every 2 ≤ i ≤ e - 2 and e ≥ 7. We also propose an open question that if an h-vector (h₀, h₁, …, h_e) with h₁ = 4e - 4, 4e - 3 < h₂ ≤ (h₁)₍₁₎|⁺¹₊₁, and h₂ ≤ h_i is a Gorenstein sequence, then h₂ = h_i for every 2 ≤ i ≤ e - 2 and e ≥ 6.

• Journal of the Chungcheong Mathematical Society
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• v.4 no.1
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• pp.11-38
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• 1991

Let $E_n$ be the real ordered space of all $n{\times}n$ Hermitian Matrices and let T be a positive linear operator from $E_2$ to $E_3$. We prove in this paper that T is extreme if and only if T is unitarily equivalent to a map of the form $S_z$ for some $z{\in}C^2$ where $S_z$ is defined by $S_z(xx^*)=ww^*$, $w_i=x_iz_i$ for i = 1, 2 and $w_3=0$.

• Bulletin of the Korean Mathematical Society
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• v.22 no.2
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• pp.121-126
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• 1985

D.K. Harrison [5] has shown that if R and S are fields of characteristic different from 2, then two Witt rings W(R) and W(S) are isomorphic if and only if W(R)/I(R)$^{3}$ and W(S)/I(S)$^{3}$ are isomorphic where I(R) and I(S) denote the fundamental ideals of W(R) and W(S) respectively. In [1], J.K. Arason and A. Pfister proved a corresponding result when the characteristics of R and S are 2, and, in [9], K.I. Mandelberg proved the result when R and S are commutative semi-local rings having 2 a unit. In this paper, we prove the result when R and S are 2-fold full rings. Throughout this paper, unless otherwise specified, we assume that R is a commutative ring having 2 a unit. A quadratic space (V, B, .phi.) over R is a finitely generated projective R-module V with a symmetric bilinear mapping B: V*V.rarw.R which is nondegenerate (i.e., the natural mapping V.rarw.Ho $m_{R}$ (V, R) induced by B is an isomorphism), and with a quadratic mapping .phi.:V.rarw.R such that B(x,y)=(.phi.(x+y)-.phi.(x)-.phi.(y))/2 and .phi.(rx)= $r^{2}$.phi.(x) for all x, y in V and r in R. We denote the group of multiplicative units of R by U(R). If (V, B, .phi.) is a free rank n quadratic space over R with an orthogonal basis { $x_{1}$, .., $x_{n}$}, we will write < $a_{1}$,.., $a_{n}$> for (V, B, .phi.) where the $a_{i}$=.phi.( $x_{i}$) are in U(R), and denote the space by the table [ $a_{ij}$ ] where $a_{ij}$ =B( $x_{i}$, $x_{j}$). In the case n=2 and B( $x_{1}$, $x_{2}$)=1/2, we reserve the notation [ $a_{11}$, $a_{22}$] for the space.the space.e.e.e.

• Korean Journal of Mathematics
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• v.20 no.4
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• pp.423-431
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• 2012

There have been some study characterizing monoids by homological classification using the properties around projectivity, injectivity, or regularity of acts. In particular Kilp and Knauer([4]) have analyzed monoids over which all acts with one of the properties around projectivity or injectivity are regular. However Kilp and Knauer left over problems of characterization of monoids over which all regular right S-acts are (weakly) at, (weakly) injective or faithful. Among these open problems, Liu([3]) proved that all regular right S-acts are (weakly) at if and only if es is a von Neumann regular element of S for all $s{\in}S$ and $e^2=e{\in}T$, and that all regular right S-acts are faithful if and only if all right ideals eS, $e^2=e{\in}T$, are faithful. But it still remains an open question to characterize over which all regular right S-acts are weakly injective or injective. Hence the purpose of this study is to investigate the relations between regular right S-acts and weakly injective right S-acts, and then characterize the monoid over which all regular right S-acts are weakly injective.

• Molecules and Cells
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• v.25 no.2
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• pp.172-177
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• 2008

Eukaryotic translation initiation factor 5B (eIF5B) plays a role in recognition of the AUG codon in conjunction with translation factor eIF2, and promotes joining of the 60S ribosomal subunit. To see whether the eIF5B proteins of other organisms function in Saccharomyces cerevisiae, we cloned the corresponding genes from Oryza sativa, Arabidopsis thaliana, Aspergillus nidulans and Candida albican and expressed them under the control of the galactose-inducible GAL promoter in the $fun12{\Delta}$ strain of Saccharomyces cerevisiae. Expression of Candida albicans eIF5B complemented the slow-growth phenotype of the $fun12{\Delta}$ strain, but that of Aspergillus nidulance did not, despite the fact that its protein was expressed better than that of Candida albicans. The Arabidopsis thaliana protein was also not functional in Saccharomyces. These results reveal that the eIF5B in Candida albicans has a close functional relationship with that of Sacharomyces cerevisiae, as also shown by a phylogenetic analysis based on the amino acid sequences of the eIF5Bs.

• Journal of the Korean Mathematical Society
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• v.61 no.5
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• pp.923-951
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• 2024

We consider a vector bundle map F : E₁ → E₂ between Lie algebroids E₁ and E₂ over arbitrary bases M₁ and M₂. We associate to it different notions of curvature which we call A-curvature, Q-curvature, P-curvature, and S-curvature using the different characterizations of Lie algebroid structure, namely Lie algebroid, Q-manifold, Poisson and Schouten structures. We will see that these curvatures generalize the ordinary notion of curvature defined for a vector bundle, and we will prove that these curvatures are equivalent, in the sense that F is a morphism of Lie algebroids if and only if one (and hence all) of these curvatures is null. In particular we get as a corollary that F is a morphism of Lie algebroids if and only if the corresponding map is a morphism of Poisson manifolds (resp. Schouten supermanifolds).

• Journal of applied mathematics & informatics
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• v.41 no.2
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• pp.321-330
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• 2023

Let G = (V, E) be a graph. Consider the group S₃. Let g : V (G) → S₃ be a function. For each edge xy assign the label 1 if ${\lceil}{\frac{o(g(x))+o(g(y))}{2}}{\rceil}$ is odd or 0 otherwise. g is a group S₃ mean cordial labeling if |v_g(i) - v_g(j)| ≤ 1 and |e_g(0) - e_g(1)| ≤ 1, where vg(i) and e_g(y)denote the number of vertices labeled with an element i and number of edges labeled with y (y = 0, 1). The graph G with group S₃ mean cordial labeling is called group S₃ mean cordial graph. In this paper, we discuss group S3 mean cordial labeling for star related graphs.

• Communications of the Korean Mathematical Society
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• v.15 no.2
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• pp.257-261
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• 2000

Northcott and Mckerrow proved that if R is a left noe-therian ring and E is an injective left R-module, then E[x-1] is an injective left R[x]-module. In this paper we generalize Northcott and McKerrow's result so that if R is a left noetherian ring and E is an in-jective left R-module, then E[x-S] is an injective left R[xS]-module, where S is a submonoid of N (N is the set of all natural numbers).