Broad-specificity amino acid racemase, a novel non-antibiotic selectable marker for transgenic plants

Yi‑Chia Kuan,Venkatesan Thiruvengadam,Jia‑Shin Lin,Jia‑Hsin Liu,Tsan‑Jan Chen,Hsin‑Mao Wu,Wen‑Ching Wang,Liang‑Jwu Chen 한국식물생명공학회 2018 Plant biotechnology reports Vol.12 No.1

The broad-specificity amino acid racemase (Bsar) from Pseudomonas putida catalyzes the racemization of various amino acids, offering a flexible and feasible platform to develop a new non-antibiotic selectable marker system for plant transformation. In the present study, we demonstrated that a Bsar variant, Bsar-R174K, that is useful as a selectable marker gene in Arabidopsis and rice that were susceptible to l-lysine and D-alanine. The introduction of wild-type Bsar, Bsar-R174K or Bsar-R174A into E. coli lysine or asparagine auxotrophs was able to rescue the growth of these microorganisms in minimal media supplemented with selectable amino acid enantiomers. The transformation of Arabidopsis with Bsar or Bsar variants based on d-alanine selection revealed that Bsar-R174K had the greatest efficiency (2.40%), superior to kanamycin selectionbased transformation (1.10%). Whereas, l-lysine-based selection exhibited lower efficiency for Bsar-R174K (0.17%). The progenies of selected Bsar-R174K transgenic Arabidopsis revealed normal growth properties. In addition, Bsar-R174K transgenic rice was obtained on l-lysine medium with an efficiency of 0.9%, and the progenies of the transgenic rice revealed morphologically normal phenotypes comparable with their wild-type counterparts. This study presents the first report of broad range amino acid racemase Bsar-R174K as a non-antibiotic selectable marker system applied in transgenic plants.

Short Low Concentration Cisplatin Treatment Leads to an Epithelial Mesenchymal Transition-like Response in DU145 Prostate Cancer Cells

Liu, Yi-Qing,Zhang, Guo-An,Zhang, Bing-Chang,Wang, Yong,Liu, Zheng,Jiao, Yu-Lian,Liu, Ning,Zhao, Yue-Ran Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.3

Background: Prostate cancer is one of the main causes of cancer death, and drug resistance is the leading reason for therapy failure. However, how this occurs is largely unknown. We therrfore aimed to study the response of DU145 cells to cisplatin. Materials and Methods: Du145 prostate cancer cells were treated with a low dose of cisplatin for 24 h and cell viability and number were determined by MTT assay and trypan blue exclusion assay, respectively. The real time polymerase chain reaction (PCR) was used to assess responses to cisplatin treatment. Results: After 24h $2{\mu}g/ml$ treatment did not result in significant reduction in cell viability or number. However, it led to enhanced cancer cell invasiveness. E-cadherin mRNA was reduced, and vimentin, Snail, Slug, metalloproteinase 9 (MMP9) mRNA expression increased significantly, a feature of epithelial-mesenchymal transition (EMT). Conclusions: Short time low concentration cisplatin treatment leads to elevated invasiveness of DU145 cancer cells and this is possibly due to EMT.

Synthesis of Thermoresponsive Hyperbranched Polyamidoamine and the Molecular Weight, pH, and Anion Sensitive Thermoresponsive Properties Thereof

Yi Liu,Yu Chen,Xun-Yong Liu,Hua-Ji Liu,Fa Cheng 한국고분자학회 2012 Macromolecular Research Vol.20 No.6

Hyperbranched polyamidoamine (HPAMAM) polymers, chemically analogous to the commercially available PAMAM dendrimer, were modified with isobutyric anhydride to result in isobutyramide (IBAm) terminated HPAMAMs (HPAMAM-IBAm). The aqueous solutions of HPAMAM-IBAm polymers had the lower critical solution temperature (LCST). The lower molecular-weight HPAMAM-IBAm exhibited higher LCST and the LCST difference was around 18 oC for one pseudo-generation variation. Further, the hyperbranched thermoresponsive polymers exhibited much lower LCSTs than the corresponding dendrimers with similar molecular weight. The LCST of HPAMAM-IBAm was pH sensitive. At pH below 10, the LCST increased significantly upon decreasing the pH,whereas, at pH above 10, the LCST decreased slowly with an increasing pH value. Nine sodium salts were used to measure the anion effect on the LCST of HPAMAM-IBAm. It was found that the LCST could also be modulated up or down in a broad range by simply adding a small amount of different kinds of inorganic anions. The specific ranking of inorganic anions in salting-out HPAMAM4-IBAm polymer was in accordance with the well-known Hofmeister series.

[주제발표2] 대만 총액계약제 경험과 총액계약제가 의료계에 미치는 영향

Yi-Lien Liu 대한의사협회 의료정책연구소 2017 의료정책포럼 Vol.15 No.4

RhGLP-1 (7-36) protects diabetic rats against cerebral ischemia-reperfusion injury via up-regulating expression of Nrf2/HO-1 and increasing the activities of SOD

Yi Fang,Xiaofang Liu,Libo Zhao,Zhongna Wei,Daoli Jiang,Hua Shao,Yannan Zang,Jia Xu,Qian Wang,Yang Liu,Ye Peng,Xiaoxing Yin 대한약리학회 2017 The Korean Journal of Physiology & Pharmacology Vol.21 No.5

The present study aimed to explore the neuroprotective effect and possible mechanisms of rhGLP-1 (7-36) against transient ischemia/reperfusion injuries induced by middle cerebral artery occlusion (MCAO) in type 2 diabetic rats. First, diabetic rats were established by a combination of a high-fat diet and low-dose streptozotocin (STZ) (30 mg/kg, intraperitoneally). Second, they were subjected to MCAO for 2 h, then treated with rhGLP-1 (7-36) (10, 20, 40 μg/kg i.p.) at the same time of reperfusion. In the following 3 days, they were injected with rhGLP-1 (7- 36) at the same dose and route for three times each day. After 72 h, hypoglycemic effects were assessed by blood glucose changes, and neuroprotective effects were evaluated by neurological deficits, infarct volume and histomorphology. Mechanisms were investigated by detecting the distribution and expression of the nuclear factor erythroid-derived factor 2 related factor 2 (Nrf2) in ischemic brain tissue, the levels of phospho-PI3 kinase (PI3K)/PI3K ratio and heme-oxygenase-1 (HO-l), as well as the activities of superoxide dismutase (SOD) and the contents of malondialdehyde (MDA). Our results showed that rhGLP-1 (7-36) significantly reduced blood glucose and infarction volume, alleviated neurological deficits, enhanced the density of surviving neurons and vascular proliferation. The nuclear positive cells ratio and expression of Nrf2, the levels of P-PI3K/PI3K ratio and HO-l increased, the activities of SOD increased and the contents of MDA decreased. The current results indicated the protective effect of rhGLP-1 (7-36) in diabetic rats following MCAO/R that may be concerned with reducing blood glucose, up-regulating expression of Nrf2/HO-1 and increasing the activities of SOD.

A Multifactorial Analysis on English Adverb Placement in Korean and Chinese University Students’ Academic Writings

LIU YI,김양희,이석재 미래영어영문학회 2017 영어영문학 Vol.22 No.4

This study aims to investigate Korean and Chinese college-level students' choices for English adverb placements in their academic writings. It is a corpus-based study and all the data are from Yonsei English Learner Corpus (YELC), Chinese Learner English Corpus(CLEC), and Louvain Corpus of Native English Essays(LOCNESS). By applying a multifactorial method, all the linguistic factors influencing English adverb placement are simultaneously examined. The result presents that both English native speakers(NSs) and Korean and Chinese students are largely influenced by the L/S/C and 'scope' factors. English proficiency rather than students' first languages (L1s) are crucial to the learners' English adverb placement. In addition, the factor of adverb 'syllable' moderately affects both Korean and Chinese L1 learners' English adverb placement.

Effects of Alpha 1- and Alpha 2-Adrenoreceptor Stimulation on Galanin mRNA Expression in Primary Cultured Superior Cervical Ganglion Neurons

( Yi Xing ),( Xiu Ying Chen ),( Zhen Liu ),( Hao Li ),( Hua Xiang Liu ),( Zhen Zhong Li ) 한국응용약물학회 2011 Biomolecules & Therapeutics(구 응용약물학회지) Vol.19 No.3

Galanin (Gal) is a 29-amino-acid neuropeptide which is expressed in superior cervical ganglion (SCG) neurons and plays a trophic role in the adult animal and acts as an inhibitory modulator of cholinergic and noradrenergic neurotransmission. Whether activation or inhibition of alpha-adrenoreceptors infl uences Gal mRNA expression in SCG neurons remains unknown. Here, we have evaluated the possible regulation of Gal mRNA expression with acute (4 h) and chronic (4 days) stimulation of alpha 1- and alpha 2-adrenoreceptor agonists or antagonists in primary cultured SCG neurons. The results showed that the amount of Gal mRNA expression in cultured SCG neurons increased significantly after chronic stimulation with alpha 2-adrenoreceptor antagonist yohimbine compared with control SCG neurons at the same time point, whereas the amount of Gal mRNA expression decreased significantly after chronic stimulation with alpha 2-adrenoreceptor agonist clonidine as compared with that in control group. All these effects were not dose-dependent on the administration of alpha 2-adrenoreceptor agonist clonidine or alpha 2-adrenoreceptor antagonist yohimbine. Alpha 1-adrenoreceptor agonist phenylephrine or antagonist prazosin chronic stimulation did not have effects on Gal mRNA expression. Acute exposure of these agents did not have effects on Gal mRNA expression. The present study showed that Gal may be regulated by activation or inhibition of alpha 2-adrenoreceptors, but not alpha 1-adrenoreceptors in sympathetic neurons.

Polymorphisms in Epigenetic and Meat Quality Related Genes in Fourteen Cattle Breeds and Association with Beef Quality and Carcass Traits

Liu, Xuan,Usman, Tahir,Wang, Yachun,Wang, Zezhao,Xu, Xianzhou,Wu, Meng,Zhang, Yi,Zhang, Xu,Li, Qiang,Liu, Lin,Shi, Wanhai,Qin, Chunhua,Geng, Fanjun,Wang, Congyong,Tan, Rui,Huang, Xixia,Liu, Airong,Wu, Asian Australasian Association of Animal Productio 2015 Animal Bioscience Vol.28 No.4

Improvement for carcass traits related to beef quality is the key concern in beef production. Recent reports found that epigenetics mediates the interaction of individuals with environment and nutrition. The present study was designed to analyze the genetic effect of single nucleotide polymorphisms (SNPs) in seven epigenetic-related genes (DNMT1, DNMT3a, DNMT3b, DNMT3L, Ago1, Ago2, and HDAC5) and two meat quality candidate genes (CAPN1 and PRKAG3) on fourteen carcass traits related to beef quality in a Snow Dragon beef population, and also to identify SNPs in a total of fourteen cattle populations. Sixteen SNPs were identified and genotyped in 383 individuals sampled from the 14 cattle breeds, which included 147 samples from the Snow Dragon beef population. Data analysis showed significant association of 8 SNPs within 4 genes related to carcass and/or meat quality traits in the beef populations. SNP1 (13154420A>G) in exon 17 of DNMT1 was significantly associated with rib-eye width and lean meat color score (p<0.05). A novel SNP (SNP4, 76198537A>G) of DNMT3a was significantly associated with six beef quality traits. Those individuals with the wild-type genotype AA of DNMT3a showed an increase in carcass weight, chilled carcass weight, flank thicknesses, chuck short rib thickness, chuck short rib score and in chuck flap weight in contrast to the GG genotype. Five out of six SNPs in DNMT3b gene were significantly associated with three beef quality traits. SNP15 (45219258C>T) in CAPN1 was significantly associated with chuck short rib thickness and lean meat color score (p<0.05). The significant effect of SNP15 on lean meat color score individually and in combination with each of other 14 SNPs qualify this SNP to be used as potential marker for improving the trait. In addition, the frequencies of most wild-type alleles were higher than those of the mutant alleles in the native and foreign cattle breeds. Seven SNPs were identified in the epigenetic-related genes. The SNP15 in CAPN1 could be used as a powerful genetic marker in selection programs for beef quality improvement in the Snow Dragon Beef population.

Performance Analysis of a Stand-alone Brushless Doubly-fed Induction Generator Using a New T-type Steady-state Model

Liu, Yi,Xu, Wei,Zhi, Gang,Zhang, Junlin The Korean Institute of Power Electronics 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.4

The brushless doubly-fed induction generator (BDFIG) is a new type of dual stator winding induction generator. In such a generator, both the power winding (PW) and the control winding (CW) are housed in the stator. This paper presents the performance characteristics of a stand-alone BDFIG operation system. A new T-type steady-state model of a BDFIG is proposed. This model is more suitable for the performance analysis of stand-alone BDFIGs than the conventional Π-type steady-state model and the simplified inner core steady-state model. The characteristics of the power flow and CW current are analyzed by detailed mathematical derivations on the basis of the proposed T-type steady-state model. The analysis results are verified by experiments, which are carried out on a prototype BDFIG. The results of the performance analysis contribute to simplifying the control circuit, improving the control performance, and selecting an appropriate BDFIG for actual industrial applications.

Application of galactinol to tomato enhances tolerance to cold and heat stresses

Liu Yudong,Zhang Li,Ma Jian,Meng Sida,Pang Chunpeng,Zhao Xiaomeng,Zhang Huidong,Wang Shou,Xu Tao,He Yi,Liu Yufeng,Qi Mingfang 한국원예학회 2022 Horticulture, Environment, and Biotechnology Vol.63 No.3

Galactinol, a galactosyl donor, is the key substrate in raffinose family oligosaccharide (RFO) biosynthesis pathways. Many studies proved that galactinol also regulates some defense-related genes to be transcribed as a sugar signal under biotic and abiotic stresses. There are four galactinol synthase (SlGolS) genes in tomato. In this study, SlGolS1, SlGolS2, and SlGolS4 responded to cold stress, especially SlGolS1 stems treated for 12 h and SlGolS4 stems treated for 24 h. Under heat stress, the expression levels of SlGolS1, SlGolS2, and SlGolS3, especially SlGolS1 and SlGolS2, increased in leaves, roots, and stems. When expressed in E. coli cells, SlGolS2 and SlGolS4 enhanced cold tolerance, whereas SlGolS1 and SlGolS3 improved heat tolerance. These results suggested that SlGolS family members played different roles in tolerance to cold and heat stresses. In addition, the application of galactinol or galactinol + α-galactosidase inhibitor (DGJ) improved the cold and heat tolerances of tomato plants, whereas the single application of DGJ had no effect. Interestingly, the applications of DGJ, galactinol, and galactinol + DGJ also affected the expression levels of SlRS, SlSTS, and SlAGAL under cold and heat stresses. These findings indicated that galactinol was involved in the biosynthesis pathways of RFOs as a galactosyl donor and regulated the expression levels of RFO biosynthesis and breakdown-related genes as a sugar signal under cold and heat stresses.