Initiation of <i>Drosophila</i> chorion gene amplification requires <i>Claspin</i> and <i>mus101</i> , whereas <i>Claspin</i> , but not <i>mus101</i> , plays a major role during elongation

Choi, Seung Ho,Park, Ji&#x2010,Hong,Nguyen, Tram Thi Ngoc,Shim, Hee Jin,Song, Young&#x2010,Han John Wiley and Sons Inc. 2017 Developmental dynamics Vol.246 No.6

<▼1><P><U>Background:</U> Claspin and TopBP1 are checkpoint mediators that are required for the phosphorylation of Chk1 by ATR to maintain genomic stability. Here, we investigated the functions of <I>Drosophila Claspin</I> and <I>mus101</I> (TopBP1 ortholog) during chorion (eggshell component) gene amplification, which occurs in follicle cells in the absence of global genomic DNA replication. <B><U>Results:</U></B> Unlike <I>Drosophila mei‐41</I> (ATR ortholog) mutant embryos, <I>Claspin</I> and <I>mus101</I> mutant embryos showed severe eggshell defects resulting from defects in chorion gene amplification. EdU (5‐ethynyl‐2′‐deoxyuridine) incorporation assay during initiation and elongation stages revealed that <I>Claspin</I> and <I>mus101</I> were required for initiation, while only <I>Claspin</I> had a major role in the efficient progression of the replication forks. Claspin proteins were enriched in the amplification foci both in the initiation and elongation stage‐follicle cell nuclei in a <I>mei‐41</I>‐independent manner. The focal localization of ORC2, a component of the origin recognition complex, was not significantly affected in the <I>Claspin</I> mutant, whereas it was reduced in the <I>mus101</I> mutant. <B><U>Conclusions:</U></B><I>Drosophila Claspin</I> plays a major role in the initiation and elongation stages of chorion gene amplification by localizing to the amplification foci in a <I>mei‐41</I>‐independent manner. <I>Drosophila mus101</I> is also involved in chorion gene amplification, mostly functioning in initiation, rather than elongation. <I>Developmental Dynamics 246:466–474, 2016</I>. © 2017 The Authors Developmental Dynamics published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists</P></▼1><▼2><P><B>Key Findings</B></P><P><P>Unlike Drosophila mei-41 mutant embryos, Claspin and mus101 mutant embryos have a thin eggshell phenotype due to reduced chorion gene amplification.</P><P>Claspin is enriched in chorion gene amplification foci during replication initiation and elongation stages.</P><P>Claspin plays a role in the initiation and elongation stages of chorion gene amplification, whereas mus101 is important for initiation, but not elongation.</P></P></▼2>

Analysis of complete genome sequences of swine hepatitis E virus and possible risk factors for transmission of HEV to humans in Korea

Song, Young&#x2010,Jo,Jeong, Hyun&#x2010,Jeong,Kim, Yu&#x2010,Jin,Lee, Sang&#x2010,Won,Lee, Jung&#x2010,Bok,Park, Seung‐,Yong,Song, Chang&#x2010,Seon,Park, Hee&#x2010,Myung,Choi, In&#x2010,Soo Wiley Subscription Services, Inc., A Wiley Company 2010 Journal of Medical Virology Vol.82 No.4

<P><B>Abstract</B></P><P>The hepatitis E virus (HEV) is an emerging zoonotic agent, for which pigs are the most important reservoir. Complete genome sequences of two swine HEV strains, designated swKOR‐1 and swKOR‐2, were determined via RT‐PCR and RACE‐PCR. The strains contained genomes composed of 7,222‐ and 7,221‐bp excluding the poly(A) tails, respectively. The swKOR‐1 and swKOR‐2 strains were classified into subtype 3a of genotype 3 via phylogenetic analysis. These strains formed a distinctive cluster in the phylogenetic tree with human and swine HEVs isolated in the USA and human HEVs isolated in Japan. Anti‐HEV antibodies were identified via ELISA in 8 of 99 (8.1%) cats, whereas, among 115 cattle and 213 dogs, no HEV‐specific antibodies were detected. The conserved RNA‐dependent RNA polymerase (RdRp) gene of HEV could be detected via RT‐PCR in 8.7% of raw oysters collected from coastal regions in Korea. The HEV RNAs detected in oysters were identified as belonging to subtype 3a. The HEV RNAs in oysters most closely resembled that of the swKOR‐2 strain. They also showed a close genetic relationship with the swKOR‐1 strain and the swine and human HEVs isolated in the USA. This is the first report describing the detection in oysters of HEV that may have originated from genotype 3 swine HEV in Korea. Pigs and cats infected with HEV, as well as oysters contaminated with HEV, are potential risk factors for HEV transmission to humans. J. Med. Virol. 82:583–591, 2010. © 2010 Wiley‐Liss, Inc.</P>

RAR‐Related Orphan Receptor Gamma (ROR‐γ) Mediates Epithelial‐Mesenchymal Transition Of Hepatocytes During Hepatic Fibrosis

Kim, Sung Min,Choi, Jung Eun,Hur, Wonhee,Kim, Jung&#x2010,Hee,Hong, Sung Woo,Lee, Eun Byul,Lee, Joon Ho,Li, Tian Zhu,Sung, Pil Soo,Yoon, Seung Kew John Wiley and Sons Inc. 2017 Journal of cellular biochemistry Vol.118 No.8

<P><B>ABSTRACT</B></P><P>The epithelial‐mesenchymal transition (EMT) is involved in many different types of cellular behavior, including liver fibrosis. In this report, we studied a novel function of RAR‐related orphan receptor gamma (ROR‐γ) in hepatocyte EMT during liver fibrosis. To induce EMT in vitro, primary hepatocytes and FL83B cells were treated with TGF‐β1. Expression of ROR‐γ was analyzed by Western blot in the fibrotic mouse livers and human livers with cirrhosis. To verify the role of ROR‐γ in hepatocyte EMT, we silenced ROR‐γ in FL83B cells using a lentiviral short hairpin RNA (shRNA) vector. The therapeutic effect of ROR‐γ silencing was investigated in a mouse model of TAA‐induced fibrosis by hydrodynamic injection of plasmids. ROR‐γ expression was elevated in hepatocyte cells treated with TGF‐β1, and ROR‐γ protein levels were elevated in the fibrotic mouse livers and human livers with cirrhosis. Knockdown of ROR‐γ resulted in the attenuation of TGF‐β1‐induced EMT in hepatocytes. Strikingly, ROR‐γ bound to ROR‐specific DNA response elements (ROREs) in the promoter region of TGF‐β type I receptor (Tgfbr1) and Smad2, resulting in the downregulation of Tgfbr1 and Smad2 after silencing of ROR‐γ. Therapeutic delivery of shRNA against ROR‐γ attenuated hepatocyte EMT and ameliorated liver fibrosis in a mouse model of TAA‐induced liver fibrosis. Overall, our results suggest that ROR‐γ regulates TGF‐β‐induced EMT in hepatocytes during liver fibrosis. We suggest that ROR‐γ may become a potential therapeutic target in treating liver fibrosis. J. Cell. Biochem. 118: 2026–2036, 2017. © 2016 The Authors. <I>Journal of Cellular Biochemistry</I> Published by Wiley Periodicals Inc.</P>

Phenyl 2‐pyridyl ketoxime induces cellular senescence‐like alterations via nitric oxide production in human diploid fibroblasts

Yang, Kyeong Eun,Jang, Hyun&#x2010,Jin,Hwang, In&#x2010,Hu,Chung, Young&#x2010,Ho,Choi, Jong&#x2010,Soon,Lee, Tae&#x2010,Hoon,Chung, Yun&#x2010,Jo,Lee, Min&#x2010,Seung,Lee, Mi Young,Yeo, Eui&#x2010,J BLACKWELL PUBLISHING 2016 AGING CELL Vol.15 No.2

<P><B>Summary</B></P><P>Phenyl‐2‐pyridyl ketoxime (PPKO) was found to be one of the small molecules enriched in the extracellular matrix of near‐senescent human diploid fibroblasts (HDFs). Treatment of young HDFs with PPKO reduced the viability of young HDFs in a dose‐ and time‐dependent manner and resulted in senescence‐associated β‐galactosidase (SA‐β‐gal) staining and G2/M cell cycle arrest. In addition, the levels of some senescence‐associated proteins, such as phosphorylated ERK1/2, caveolin‐1, p53, p16<SUP>ink4a</SUP>, and p21<SUP>waf1</SUP>, were elevated in PPKO‐treated cells. To monitor the effect of PPKO on cell stress responses, reactive oxygen species (ROS) production was examined by flow cytometry. After PPKO treatment, ROS levels transiently increased at 30 min but then returned to baseline at 60 min. The levels of some antioxidant enzymes, such as catalase, peroxiredoxin II and glutathione peroxidase I, were transiently induced by PPKO treatment. SOD II levels increased gradually, whereas the SOD I and III levels were biphasic during the experimental periods after PPKO treatment. Cellular senescence induced by PPKO was suppressed by chemical antioxidants, such as N‐acetylcysteine, 2,2,6,6‐tetramethylpiperidinyloxy, and L‐buthionine‐(<I>S</I>,<I>R</I>)‐sulfoximine. Furthermore, PPKO increased nitric oxide (NO) production via inducible NO synthase (iNOS) in HDFs. In the presence of NOS inhibitors, such as L‐NG‐nitroarginine methyl ester and L‐NG‐monomethylarginine, PPKO‐induced transient NO production and SA‐β‐gal staining were abrogated. Taken together, these results suggest that PPKO induces cellular senescence in association with transient ROS and NO production and the subsequent induction of senescence‐associated proteins<B>.</B></P>

Enhanced production of 2,3‐butanediol in pyruvate decarboxylase‐deficient <i>Saccharomyces cerevisiae</i> through optimizing ratio of glucose/galactose

Choi, Eun&#x2010,Ji,Kim, Jin&#x2010,Woo,Kim, Soo&#x2010,Jung,Seo, Seung‐,Oh,Lane, Stephan,Park, Yong&#x2010,Cheol,Jin, Yong&#x2010,Su,Seo, Jin&#x2010,Ho WILEY‐VCH Verlag 2016 Biotechnology Journal Vol.11 No.11

<P><B>Abstract</B></P><P>Galactose and glucose are two of the most abundant monomeric sugars in hydrolysates of marine biomasses. While <I>Saccharomyces cerevisiae</I> can ferment galactose, its uptake is tightly controlled in the presence of glucose by catabolite repression. It is desirable to construct engineered strains capable of simultaneous utilization of glucose and galactose for producing biofuels and chemicals from marine biomass. The <I>MTH1</I> gene coding for transcription factor in glucose signaling was mutated in a pyruvate decarboxylase (Pdc)‐deficient <I>S. cerevisiae</I> expressing heterologous 2,3‐butanediol (2,3‐BD) biosynthetic genes. The engineered <I>S. cerevisiae</I> strain consumed glucose and galactose simultaneously and produced 2,3‐BD as a major product. Total sugar consumption rates increased with a low ratio of glucose/galactose, though, occurrence of the glucose depletion in a fed‐batch fermentation decreased 2,3‐BD production substantially. Through optimizing the profiles of sugar concentrations in a fed‐batch cultivation with the engineered strain, 99.1 ± 1.7 g/L 2,3‐BD was produced in 143 hours with a yield of 0.353 ± 0.022 g 2,3‐BD/g sugars. This result suggests that simultaneous and efficient utilization of glucose and galactose by the engineered yeast might be applicable to the economical production of not only 2,3‐BD, but also other biofuels and chemicals from marine biomass.</P>

Overexpression of <i>OsTF1L,</i> a rice HD‐Zip transcription factor, promotes lignin biosynthesis and stomatal closure that improves drought tolerance

Bang, Seung Woon,Lee, Dong&#x2010,Keun,Jung, Harin,Chung, Pil Joong,Kim, Youn Shic,Choi, Yang Do,Suh, Joo&#x2010,Won,Kim, Ju&#x2010,Kon BLACKWELL 2019 PLANT BIOTECHNOLOGY JOURNAL Vol.17 No.1

<P><B>Summary</B></P><P>Drought stress seriously impacts on plant development and productivity. Improvement of drought tolerance without yield penalty is a great challenge in crop biotechnology. Here, we report that the rice (<I>Oryza sativa</I>) homeodomain‐leucine zipper transcription factor gene, <I>OsTF1L</I> (<I>Oryza sativa transcription factor 1‐like</I>), is a key regulator of drought tolerance mechanisms. Overexpression of the <I>OsTF1L</I> in rice significantly increased drought tolerance at the vegetative stages of growth and promoted both effective photosynthesis and a reduction in the water loss rate under drought conditions. Importantly, the <I>OsTF1L</I> overexpressing plants showed a higher drought tolerance at the reproductive stage of growth with a higher grain yield than nontransgenic controls under field‐drought conditions. Genomewide analysis of <I>OsTF1L</I> overexpression plants revealed up‐regulation of drought‐inducible, stomatal movement and lignin biosynthetic genes. Overexpression of <I>OsTF1L</I> promoted accumulation of lignin in shoots, whereas the RNAi lines showed opposite patterns of lignin accumulation. <I>OsTF1L</I> is mainly expressed in outer cell layers including the epidermis, and the vasculature of the shoots, which coincides with areas of lignification. In addition, <I>OsTF1L</I> overexpression enhances stomatal closure under drought conditions resulted in drought tolerance. More importantly, OsTF1L directly bound to the promoters of lignin biosynthesis and drought‐related genes involving <I>poxN/PRX38</I>,<I> Nodulin protein</I>,<I>DHHC4</I>,<I>CASPL5B1</I> and <I>AAA‐type ATPase</I>. Collectively, our results provide a new insight into the role of <I>OsTF1L</I> in enhancing drought tolerance through lignin biosynthesis and stomatal closure in rice.</P>

The rice Os NAC 6 transcription factor orchestrates multiple molecular mechanisms involving root structural adaptions and nicotianamine biosynthesis for drought tolerance

Lee, Dong&#x2010,Keun,Chung, Pil Joong,Jeong, Jin Seo,Jang, Geupil,Bang, Seung Woon,Jung, Harin,Kim, Youn Shic,Ha, Sun&#x2010,Hwa,Choi, Yang Do,Kim, Ju&#x2010,Kon BLACKWELL 2017 PLANT BIOTECHNOLOGY JOURNAL Vol.15 No.6

<P><B>Summary</B></P><P>Drought has a serious impact on agriculture worldwide. A plant's ability to adapt to rhizosphere drought stress requires reprogramming of root growth and development. Although physiological studies have documented the root adaption for tolerance to the drought stress, underlying molecular mechanisms is still incomplete, which is essential for crop engineering. Here, we identified <I>OsNAC6</I>‐mediated root structural adaptations, including increased root number and root diameter, which enhanced drought tolerance. Multiyear drought field tests demonstrated that the grain yield of <I>OsNAC6</I> root‐specific overexpressing transgenic rice lines was less affected by drought stress than were nontransgenic controls. Genome‐wide analyses of loss‐ and gain‐of‐function mutants revealed that OsNAC6 up‐regulates the expression of direct target genes involved in membrane modification, nicotianamine (NA) biosynthesis, glutathione relocation, 3′‐phophoadenosine 5′‐phosphosulphate accumulation and glycosylation, which represent multiple drought tolerance pathways. Moreover, overexpression of <I>NICOTIANAMINE SYNTHASE</I> genes, direct targets of OsNAC6, promoted the accumulation of the metal chelator NA and, consequently, drought tolerance. Collectively, OsNAC6 orchestrates novel molecular drought tolerance mechanisms and has potential for the biotechnological development of high‐yielding crops under water‐limiting conditions.</P>

Incidence, predictors, and outcomes of distal vessel expansion on follow‐up intravascular ultrasound after recanalization of chronic total occlusions using new‐generation drug‐eluting stents: Data from the CTO‐IVUS randomized

Hong, Sung&#x2010,Jin,Kim, Byeong&#x2010,Keuk,Kim, Young&#x2010,Joo,Rha, Seung‐,Woon,Lee, Seung‐,Jin,Kim, Hee&#x2010,Yeol,Choi, Jin&#x2010,Ho,Ahn, Chul&#x2010,Min,Kim, Jung&#x2010,Sun,Ko, John WileySons, Inc. 2020 Catheterization and cardiovascular interventions Vol.95 No.1

<P><B>Abstract</B></P><P><B>Objectives</B></P><P>To evaluate the incidence, predictors, and outcomes of distal vessel expansion on intravascular ultrasound (IVUS) after recanalization of chronic total occlusion (CTO) particularly using new‐generation drug‐eluting stent (DES).</P><P><B>Background</B></P><P>The luminal changes of narrowed vessels distal to CTO segments after recanalization using new‐generation DES have rarely been studied.</P><P><B>Methods</B></P><P>This substudy of the CTO‐IVUS (Chronic Total Occlusion InterVention with drUg‐eluting Stents) trial included a total of 69 new‐generation DES‐treated CTOs with serial matched IVUS analyses at index percutaneous coronary intervention (PCI) and at 1‐year follow‐up. The predictors of distal vessel expansion, any increase of lumen area at the distal reference (LA<SUB>distal</SUB>) on 1‐year follow‐up IVUS, were evaluated by multivariable binary logistic analyses.</P><P><B>Results</B></P><P>Distal vessel expansion was identified in 46 (67%). Independent determinants of distal vessel expansion were proximal CTO, a smaller LA<SUB>distal</SUB> at the index PCI, a greater minimal stent area‐to‐LA<SUB>distal</SUB> (MSA‐to‐LA<SUB>distal</SUB>) ratio, and a greater lumen area at the distal stent edge‐to‐LA<SUB>distal</SUB> (LA<SUB>edge</SUB>‐to‐LA<SUB>distal</SUB>) ratio. The cut‐off values of a MSA‐to‐LA<SUB>distal</SUB> ratio and a LA<SUB>edge</SUB>‐to‐LA<SUB>distal</SUB> ratio predicting the distal vessel expansion by receiver operating characteristic curve analysis were 1.0 and 1.1, respectively. During the median 5.1 years, rates of target vessel revascularization, cardiac death, and stent thrombosis were similar in the distal vessel‐expanded and nonexpanded groups.</P><P><B>Conclusion</B></P><P>After opening CTO with new‐generation DES, two‐thirds of patients exhibited distal vessel expansion on 1‐year follow‐up IVUS. Expansion determinants were a proximal CTO, lower LA<SUB>distal</SUB>, and larger stent areas relative to the LA<SUB>distal</SUB> (modifiable procedural predictors).</P>

Decreased hippocampal brain‐derived neurotrophic factor and impaired cognitive function by hypoglossal nerve transection in rats

Kim, Doyun,Chung, Sena,Lee, Seung‐,Hyun,Choi, Se&#x2010,Young,Kim, Soung&#x2010,Min,Koo, JaeHyung,Lee, Jong&#x2010,Ho,Jahng, Jeong Won CAROL DAVILA UNIVERSITY PRESS 2017 Journal of Cellular and Molecular Medicine Vol.21 No.12

<P><B>Abstract</B></P><P>The hypoglossal nerve controls tongue movements, and damages of it result in difficulty in mastication and food intake. Mastication has been reported to maintain hippocampus‐dependent cognitive function. This study was conducted to examine the effect of tongue motor loss on the hippocampus‐dependent cognitive function and its underlying mechanism. Male Sprague Dawley rats were subjected to the initial training of Morris water maze task before or after the bilateral transection of hypoglossal nerves (Hx). When the initial training was given before the surgery, the target quadrant dwelling time during the probe test performed at a week after the surgery was significantly reduced in Hx rats relative to sham‐operated controls. When the initial training was given after the surgery, Hx affected the initial and reversal trainings and probe tests. Brain‐derived neurotrophic factor (BDNF) expression, cell numbers and long‐term potentiation (LTP) were examined in the hippocampus on the 10<SUP>th</SUP> day, and BrdU and doublecortin staining on the 14<SUP>th</SUP> day, after the surgery. Hx decreased the hippocampal BDNF and cells in the CA1/CA3 regions and impaired LTP. BrdU and doublecortin staining was decreased in the dentate gyrus of Hx rats. Results suggest that tongue motor loss impairs hippocampus‐dependent cognitive function, and decreased BDNF expression in the hippocampus may be implicated in its underlying molecular mechanism in relation with decreased neurogenesis/proliferation and impaired LTP.</P>

Transforming growth factor‐β induces epithelial to mesenchymal transition and suppresses the proliferation and transdifferentiation of cultured human pancreatic duct cells

Shin, Jeong&#x2010,Ah,Hong, Oak&#x2010,Kee,Lee, Hye&#x2010,Jung,Jeon, Sung&#x2010,Yoon,Kim, Ji&#x2010,Won,Lee, Seung‐,Hwan,Cho, Jae&#x2010,Hyoung,Lee, Jung&#x2010,Min,Choi, Yoon&#x2010,Hee,Chang Wiley Subscription Services, Inc., A Wiley Company 2011 Journal of cellular biochemistry Vol.112 No.1

<P><B>Abstract</B></P><P>Pancreatic duct cells are considered a potential source of β‐cell regeneration, and transforming growth factor‐β (TGF‐β) has been suggested to perform an important role in these processes, but the underlying mechanism of the signal pathways, especially in humans, remains poorly understood. To evaluate the role of TGF‐β1, pancreatic duct cells were isolated from three brain‐dead organ donors. Pancreatic cell clusters harvested after islet isolation were dispersed to single cells and cultured in monolayers, then treated with TGF‐β1. We analyzed the characteristics of the cultured cells, the TGF‐β1 intracellular signaling pathway, the proliferation, and transdifferentiation rates of the duct cells. We also evaluated the genes and protein expression patterns after TGF‐β1 treatment. After TGF‐β1 treatment, typical morphologic changes representative of EMT were observed and Erk1/2, JNK, and AKT phosphorylation, Ras downstream effectors, were increased. β cell‐specific transcription factors including PDX‐1, Beta2/NeuroD, Ist‐1, and NGN3 were markedly suppressed and the rate of transdifferentiation into β cells was also suppressed. Genomic and proteomic analyses suggested that TGF‐β1 induces marked changes in a variety of structural genes and proteins associated with EMT. In conclusion, TGF‐β1 induces EMT in cultured human pancreatic duct cells, but suppresses its proliferation and transdifferentiation into β cells. Our results are the first report of TGF‐β1 effects for EMT and ductal cell transdifferentiation and proliferation at the protein level in human pancreatic duct cells. J. Cell. Biochem. 112: 179–188, 2011. © 2010 Wiley‐Liss, Inc.</P>