• BMB Reports
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• 제42권1호
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• pp.22-27
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• 2009

Replication Protein A (RPA) is a single stranded DNA-binding protein involved in DNA metabolic activities such as replication, repair, and recombination. RPA-Interacting Protein $\alpha$ ($RIP{\alpha}$) was originally identified as a nuclear transporter of RPA in Xenopus. The human $RIP{\alpha}$ gene encodes several splice isoforms, of which $hRIP{\alpha}$ and $hRIP{\beta}$ are the major translation products in vivo. However, limited information is available about the alternative splicing of $RIP{\alpha}$ in eukaryotes, apart from that in humans. In this study, we examined the alternative splicing of RIP{\alpha} in the Drosophila, Xenopus, and mouse system. We showed that the number of splice isoforms of RIP{\alpha} was species-specific, and displayed a tendency to increase in higher eukaryotes. Moreover, a mouse ortholog of $hRIP{\alpha}$, $mRIP{\beta}2$, was not SUMOylated, in contrast to $hRIP{\alpha}$. Based on these results, we suggest that the $RIP{\alpha}$ gene gains more splice isoforms and additional modifications after molecular evolution.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2001년도 추계학술대회 및 정기총회
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• pp.108-108
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• 2001

Axin2/Conductin/Axil and its ortholog Axin are negative regulators of the Wnt signaling pathway, which promote the phosphorylation and degradation of ${\beta}$-catenin. While Axin is expressed ubiquitously, Axin2 mRNA was seen in a restricted pattern during mouse embryogenesis and organogenesis. Because many sites of Axin2 expression overlapped with those of several Wnt genes, we tested whether Axin2 was induced by Wnt signaling. Endogenous Axin2 mRNA and protein expression could be rapidly induced by activation of the Wnt pathway, and Axin2 reporter constructs, containing a 5.6 kb DNA fragment including the promoter and first intron, were also induced. This genomic region contains eight Tcf/LEF consensus binding sites, five of which are located within longer, highly conserved non-coding sequences. The mutation or deletion of these Tcf/LEF sites greatly diminished induction by ${\beta}$-catenin, and mutation of the Tcf/LEF site T2 abolished protein binding in an electrophoretic mobility-shift assay. These results strongly suggest that Axin2 is a direct target of the Wnt pathway, mediated through Tcf/LEF factors. The 5.6 kb genomic sequence was sufficient to direct the tissue specific expression of d2EGFP in transgenic embryos, consistent with a role for the Tcf/LEF sites and surrounding conserved sequences in the in vivo expression pattern of Axin2. Our results suggest that Axin2 participates in a negative feedback loop, which could serve to limit the duration or intensity of a Wnt-initiated signal.

• The Plant Pathology Journal
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• 제36권4호
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• pp.314-322
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• 2020

Interplay between histone acetylation and deacetylation is one of the key components in epigenetic regulation of transcription. Here we report the requirement of MoHDA1-mediated histone deacetylation during asexual development and pathogenesis for the rice blast fungus, Magnaporthe oryzae. Structural similarity and phylogenetic analysis suggested that MoHDA1 is an ortholog of Saccharomyces cerevisiae Hda1, which is a representative member of class II histone deacetylases. Targeted deletion of MoHDA1 caused a little decrease in radial growth and large reduction in asexual sporulation. Comparison of acetylation levels for H3K9 and H3K14 showed that lack of MoHDA1 gene led to significant increase in H3K9 and H3K14 acetylation level, compared to the wild-type and complementation strain, confirming that it is a bona fide histone deacetylase. Expression analysis on some of the key genes involved in asexual reproduction under sporulation-promoting condition showed almost no differences among strains, except for MoCON6 gene, which was up-regulated more than 6-fold in the mutant than wild-type. Although the deletion mutant displayed little defects in germination and subsequent appressorium formation, the mutant was compromised in its ability to cause disease. Wound-inoculation showed that the mutant is impaired in invasive growth as well. We found that the mutant was defective in appressorium-mediated penetration of host, but did not lose the ability to grow on the media containing H₂O₂. Taken together, our data suggest that MoHDA1-dependent histone deacetylation is important for efficient asexual development and infection of host plants in M. oryzae.

• 한국수산과학회지
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• 제48권6호
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• pp.913-919
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• 2015

In vertebrates, the vitamin D receptor (VDR), a member of the nuclear receptor superfamily, binds the biologically active ligand $1{\alpha},25-(OH)_2$-vitamin $D_3$ (1,25 $D_3$). Nearly all vertebrates, including Agnatha, possess a VDR with high ligand selectivity for 1,25 $D_3$ and related metabolites. Although a putative ancestral VDR gene is present in the genome of the chordate invertebrate Ciona intestinalis, the functional characteristics of marine invertebrate VDR are still obscure. To elucidate the ascidian Halocynthia roretzi VDR (HrVDR), we cloned full-length HrVDR cDNA and investigated the transcriptional activity of HrVDR in HEK293 cells. HrVDR consists of 1,680 nucleotides (559 amino acids [aa]), including a short N-terminal region (A/B domain; 26 aa), DNA-binding domain (C domain; 72 aa), hinge region (D domain; 272 aa), and C-terminal ligand-binding domain (E domain; 161 aa). The amino acid sequence identity of HrVDR was greatest to that of C. intestinalis VDR (56%). In the luciferase reporter assays, the transcriptional activity of HrVDR was not significantly increased by 1,25 $D_3$, whereas the farnesoid X receptor agonist GW4064 increased the transactivation of HrVDR. These results suggest the presence of a novel ligand for and a distinct ligand-binding domain in ascidian VDR.

• 미생물학회지
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• 제50권3호
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• pp.249-253
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• 2014

THOC7/Mft1는 mRNA가 전사되는 동안 mRNP의 포장과 mRNA 방출에 관여하는 진화적으로 잘 보존된 THO 복합체의 구성인자이다. 분열효모 Schizosaccharomyces pombe에서 THOC7/Mft1의 이종상동체(spThoc7)가 합성치사 돌연변이체 SLRsm1의 생장 결함을 부분적으로 상보하는 것으로 선별되었다. 이배체 S. pombe 균주에 하나의 spthoc7 유전자만을 결실시킨 후 4분체 분석을 수행한 결과, 이 유전자는 생장에 필수적이지 않았다. 하지만, ${\Delta}thoc7$ 결실돌연변이는 생장과 mRNA의 핵에서 세포질로의 방출에 약간의 결함을 보였다. 기능을 하는 spThoc7-GFP단백질은 주로 핵 안에 존재하였다. 이와 같은 결과들은 spThoc7도 mRNA 방출에 관여하고 있음을 시사한다.

• The Plant Pathology Journal
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• 제32권4호
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• pp.281-289
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• 2016

The transcription cofactor Swi6 plays important roles in regulating vegetative growth and meiosis in Saccharomyces cerevisiae. Functions of Swi6 ortholog were also characterized in Fusarium graminearum which is one of the devastating plant pathogenic fungi. Here, we report possible role of FgSwi6 in the interaction between F. graminearum and Fusarium graminearum virus 1 (FgV1) strain DK21. FgV1 perturbs biological characteristics of host fungi such as vegetative growth, sporulation, pigmentation, and reduction of the virulence (hypovirulence) of its fungal host. To characterize function(s) of FgSWI6 gene during FgV1 infection, targeted deletion, over-expression, and complementation mutants were generated and further infected successfully with FgV1. Deletion of FgSwi6 led to severe reduction of vegetative growth even aerial mycelia while over-expression did not affect any remarkable alteration of phenotype in virus-free isolates. Virus-infected (VI) FgSWI6 deletion isolate exhibited completely delayed vegetative growth. However, VI FgSWI6 over-expression mutant grew faster than any other VI isolates. To verify whether these different growth patterns in VI isolates, viral RNA quantification was carried out using qRT-PCR. Surprisingly, viral RNA accumulations in VI isolates were similar regardless of introduced mutations. These results provide evidence that FgSWI6 might play important role(s) in FgV1 induced phenotype alteration such as delayed vegetative growth.

• Plant Biotechnology Reports
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• 제4권1호
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• pp.53-59
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• 2010

A specific deleted version of ARABIDOPSIS RESPONSE REGULATOR1 (ARR1) lacking the signal receiver domain (1.152 amino acids)-coding sequence, referred to as $ARR1{\Delta}DDK$, was amplified using Arabidopsis thaliana cDNA prepared from adult leaves and transferred into the genome of Nicotiana tabacum cv. Samsun under the transcriptional control of a ${\beta}$-estradiol-inducible expression system. The ectopic expression of $ARR1{\Delta}DDK$ affected the morphology of transgenic seedlings and their segments in vitro. In the presence of an inducer, ${\beta}$-estradiol, ectopic expression of $ARR1{\Delta}DDK$ induced only the formation of soft, pseudo-bulbous tissue in the root tip region of intact seedlings, which appeared similar to callus generated on a hypocotyl segment in the presence of 2,4-D and 6-benzyladenine (BA), both at $1\;{\mu}M$. Those callus tissues on the root tip region could not generate shoots unless $1\;{\mu}M$ BA was supplied. In segment culture, ectopic expression of $ARR1{\Delta}DDK$ induced calluslike tissue around the cut-end of cotyledon and hypocotyl segments with occasional shoot formation, suggesting that the expression of $ARR1{\Delta}DDK$ could substitute for the effects of cytokinin on these segments. Additionally, treatment with only ${\beta}$-estradiol induced NtWUS, a WUS ortholog in tobacco, which was detected during the process of callus tissue formation in the root tip region and also in cotyledon or hypocotyl segments. These findings suggest that the NtWUS might be associated in the transdifferentiation process caused by the functional regulation of $ARR1{\Delta}DDK$ in transgenic tobacco seedlings.

• 미생물학회지
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• 제51권2호
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• pp.181-185
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• 2015

Tho2/THOC2는 전사 과정을 mRNA 성숙 및 방출과 연결함으로써 mRNP의 생성에 중요한 역할을 담당하는 THO 복합체의 구성인자이다. 분열효모 Schizosaccharomyces pombe의 유전체 데이터에서 Tho2/THOC2의 이종상동체를 찾아 기능을 분석하였다. 4분체 분석 결과 이 유전자는 생장에 필수적이었다. S. pombe tho2 유전자의 발현을 억제하거나 과발현시키면 생장이 저해되는데, 세포의 길이가 길어지고 비정상적인 DNA분포와 $poly(A)^+$ RNA가 핵 안에 축적되는 표현형을 보였다. 또한 정상적인 기능을 가진 GFP-Tho2 단백질은 주로 핵 안에 존재하였다. Yeast two-hybrid 분석에서 Tho2는 THO 복합체의 또 다른 구성인자인 Tex1과 상호작용을 하였다. 이와 같은 결과들은 S. pombe의 Tho2 상동체도 THO 복합체의 구성인자로 mRNA 방출에 관여하고 있음을 시사한다.

• 생명과학회지
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• 제24권7호
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• pp.791-797
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• 2014

원핵과 진핵생물에 공통 보존적인 OG (Orthologous Group of proteins)를 미토콘드리아 관련 OG와 비관련 OG로 나누어 분석하였다. 62개의 원핵-진핵생물 공통적 COG (Clusters of OG)중 20개가 미토콘드리아 관련 OG였고 이들은 모두 번역관련 OG로 생명현상에서의 단백질의 중요성을 확인할 수 있었다. 세포내 절대기생체인 뇌회백염원충은 비교대상 다른 생물들 모두에 공통적인 미토콘드리아 관련 OG가 전혀 없었다. 뇌회백염원충을 제외한 6개 진핵생물과 원핵생물 63종에 모두 보존적인 미토콘드리아 관련 OG는 17개였다. Phylogenetic tree의 distance 분석을 수행하니 보존적 OG가 원핵생물에서 미토콘드리아 관련 OG와 비관련 OG 등 각각 2개의 그룹으로 나누어 졌고(p<0.001, paired t-test) 진핵생물은 그렇지 않았다(p>0.05, paired t-test). 보존성이 가장 높은 ortholog는 미토콘드리아 관련 OG에서는 COG0048-KOG1750 (ribosomal small subunit S12)이었고, 미토콘드리아 비관련 OG에서는 COG0100-KOG0407 (ribosomal small subunit S11)이었다. 본 연구결과는 진화관계 등의 기초학문적 연구와 치료제 개발 등의 자료가 될 수 있을 것이다.

• 한국축산식품학회지
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• 제37권1호
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• pp.134-138
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• 2017

Salmonella enterica infects a broad range of host animals, and zoonostic infection threatens both public health and the livestock and meat processing industries. Many antimicrobials have been developed to target Salmonella envelope that performs essential bacterial functions; however, there are very few analytical methods that can be used to validate the efficacy of these antimicrobials. In this study, to develop a potential biosensor for Salmonella envelope stress, we examined the transcription of the S. enterica serovar typhimurium spy gene, the ortholog of which in Escherichia coli encodes Spy (${\underline{s}}pheroplast$ ${\underline{p}}rotein$ ${\underline{y}}$). Spy is a chaperone protein expressed and localized in the periplasm of E. coli during spheroplast formation, or by exposure to protein denaturing conditions. spy expression in S. typhimurium was examined by constructing a spy-gfp transcriptional fusion. S. typhimurium spy transcription was strongly induced during spheroplast formation, and also when exposed to membrane-disrupting agents, including ethanol and the antimicrobial peptide polymyxin B. Moreover, spy induction required the activity of regulator proteins BaeR and CpxR, which are part of the major envelope stress response systems BaeS/BaeR and CpxA/CpxR, respectively. Results suggest that monitoring spy transcription may be useful to determine whether a molecule particularly cause envelope stress in Salmonella.