Establishment and Application of Target Gene Disruption System in Saccharomyces boulardii

Longjiang Wang,Hui Sun,Jie Zhang,Qing Liu,Tiantian Wang,Peipei Chen,Hongmei Li,Yihong Xiao,Fangkun Wang,Xiaomin Zhao 한국생물공학회 2015 Biotechnology and Bioprocess Engineering Vol.20 No.1

Saccharomyces boulardii is the best knownprobiotic yeast, widely used as a therapeutic agent for thetreatment or prevention of diarrhea and intestine disorders. In the present work, we established a target gene disruptionsystem for S. boulardii based on the Cre-loxP system usedfor S. cerevisiae and other fungi by screening out selectionmarkers, working out the transformation method, andconstructing essential plasmids for S. boulardii. Theestablished system was successfully applied to the URA3gene disruption and created an ura3 null mutant strain ofS. boulardii. The system can be used for PCR mediatedgene disruption, cloning mediated gene disruption, andreintroduction of the deleted gene back to the mutant. Allthe introduced exogenous DNAs in the gene disruptionprocedures were removed from the final mutant strainexcept the two 34 bp loxP pieces left in deleted gene loci.

Stochastic Stability, ℒ1-gain and Control Synthesis for Positive Semi-Markov Jump Systems

Longjiang Zhao,Wenhai Qi,Lihua Zhang,Yonggui Kao,Xianwen Gao 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.5

This paper treats the problems of stochastic stability, ℒ1-gain and control synthesis for positive semi- Markov jump systems (S-MJSs). The system under consideration involves semi-Markov stochastic process related to Weibull distribution. The main motivation for this paper is that the positive condition sometimes needs to be considered in S-MJSs and the controller design methods in the existing works have some conservation. To deal with these problems, some sufficient conditions for stochastic stability of positive S-MJSs are established by implying the linear co-positive Lyapunov function. Then, some sufficient conditions for ℒ1-gain constraint are also presented, upon which, a state feedback controller is designed by decomposing the controller gain matrix such that the resulting closed-loop system is positive and stochastically stable with ℒ1-gain performance in the form of standard linear programming (LP). The advantages of the new framework lie in the following facts: (1) the weak infinitesimal operator is derived for S-MJSs under the constraint of positive condition and (2) the less conservative stabilizing controller is designed to achieve the desired control performance. Finally, numerical examples are given to demonstrate the validity of the main results.

TCP10L negatively regulates alpha-fetoprotein expression in hepatocellular carcinoma

Suqin Shen,Huan Feng,Longjiang Liu,Wei Su,Jiaxue Wu,Long Yu 생화학분자생물학회 2020 BMB Reports Vol.53 No.8

Alpha-fetoprotein (AFP) is one of the most commonly used and reliable biomarkers for Hepatocellular carcinoma (HCC). However, the underlying mechanism of AFP expression in HCC is poorly understood. In this study, we found that TCP10L, a gene specifically expressed in the liver, is down-regulated in HCC and that its expression inversely correlates with AFP expression. Moreover, overexpression of TCP10L suppresses AFP expression whereas knockdown of TCP10L increases AFP expression, suggesting that TCP10L might be a negative regulator of AFP. We found that TCP10L is associated with the AFP promoter and inhibits AFP promoter-driven transcriptional activity. Taken together, these results indicate that TCP10L negatively regulates AFP expression in HCC and that it could be a potential prognostic marker and therapeutic target for HCC.

Comparative Study of the marR Genes within the Family Enterobacteriaceae

Dan Wang,Changjiang Guo,Longjiang Gu,Xiaohui Zhang 한국미생물학회 2014 The journal of microbiology Vol.52 No.6

marR genes are members of an ancient family originallyidentified in Escherichia coli. This family is widely distributedin archaea and bacteria. Homologues of this family have aconserved winged helix fold. MarR proteins are involved innon-specific resistance systems conferring resistance to multipleantibiotics. Extensive studies have shown the importanceof MarR proteins in physiology and pathogenicity inEnterobacteria, but little is known about their origin or evolution. In this study, all the marR genes in 43 enterobacterialgenomes representing 14 genera were identified, and the phylogeneticrelationships and genetic parameters were analyzed. Several major findings were made. Three conserved marRgenes originated earlier than Enterobacteriaceae and a genelossevent was found to have taken place in Yersinia pestisAntiqua. Three functional genes, rovA, hor, and slyA, werefound to be clear orthologs among Enterobacteriaceae. Thecopy number of marR genes in Enterobacteriaceae was foundto vary from 2 to 11. These marR genes exhibited a faster rateof nucleotide substitution than housekeeping genes did. Specifically, the regions of marR domain were found to besubject to strong purifying selection. The phylogenetic relationshipand genetic parameter analyses were consistentwith conservation and specificity of marR genes. These dualcharacters helped MarR to maintain a conserved bindingmotif and variable C-terminus, which are important to adaptiveresponses to a number of external stimuli in Enterobacteriaceae.

Compound fault diagnosis of bearings using improved fast spectral kurtosis with VMD

Shuting Wan,Xiong Zhang,Longjiang Dou 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.11

The fast spectrum kurtosis (FSK) algorithm can adaptively identify resonance bands of a signal, and fault characteristics can be extracted by analyzing the selected frequency bands. However, in practical applications, the bearing failure may be composed of various faults (inner ring/outer ring/rolling element) and the faults may be located in different resonant bands. Due to the interference between different fault components and noise, the weak components may be submerged when FSK is used to deal with compound fault signals. To improve the accuracy of an FSK processing compound fault located in different resonance bands, an improved FSK method combined with the variational mode decomposition (VMD) is proposed. First, the parameters (number of components K / penalty factor a ) in the VMD decomposition are selected, and the original compound fault signal is preprocessed by VMD decomposition, so that the original signal is decomposed into K variational intrinsic mode function (VIMF) components. The resonance center bands of these signals are different from each other, so the different fault information is located in different VIMF. Finally, each VIMF component is calculated by FSK. Through the simulated and experimental analysis, the method can accurately identify the resonance bands, and identify the weak fault characteristics of compound bearing fault.

On Finding the Multicast Protection Tree Considering SRLG in WDM Optical Networks

Yonggang Li,Yaohui Jin,Lemin Li,Longjiang Li 한국전자통신연구원 2006 ETRI Journal Vol.28 No.4

In this letter, a new sharing mechanism, SRLG sharing, is proposed, which allows the links of the same shared risk link group (SRLG) in a primary light tree to share protections in WDM optical networks. In previous studies, how to share spare resources with SRLG constraints has not been studied in multicast optical networks. In this letter, considering SRLG sharing, we propose a novel algorithm –multicast with SRLG sharing (MSS)– to establish a protection light tree. Finally, the algorithm MSS and the algorithm multicast with no SRLG sharing (MNSS) are compared through a simulation to show that our new sharing scheme of SRLG sharing is more efficient than that of no SRLG sharing in terms of spare resource utilization and blocking probability.

The Production and Cytological Analysis of Brassica napus -B Genome Chromosome Monosomic Addition Lines and Their Hybrids

Li Maoteng,Xiang Jun,Liu Jianmin,Yu Longjiang,Li Dianrong 한국유전학회 2008 Genes & Genomics Vol.30 No.2

The Brassica napus-B genome monosomic addition lines (MALs) (AACC + B’, 2n = 39) were developed from self-pollination of pentaploid hybrids (AABCC) that were derived from hybridization between hexaploid hybrids (AABBCC) and B. napus (AACC). The alien chromosomes of the B genome in MALs were identified by the GISH technique, by observation of the meiotic behavior of pollen mother cells (PMCs), and by B-genome-specific molecular marker analysis. Studies of the meiotic behavior of B. napus-B genome chromosome MALs at diakinesis revealed that the majority of the chromosome configuration was 19²+1¹, which indicated that the alien B genome chromosome remained univalent in most cases. The laggard-free PMCs also appeared at a lower ratio, which indicated that the B genome chromosome could be transmitted into gametes. The chromosome configurations of 20² and 19²+2¹ that appeared in double MALs (AACC+ 2 chromosomes of the B genome) indicated different homoeology between different B genome chromosomes. The paired B genome bivalent in double MALs can be normally segregated at anaphase in most cases. PMCs with multivalents were observed in all the double MAL combinations, which indicated homology of the B genome chromosomes with the A or C genome chromosomes. The Brassica napus-B genome monosomic addition lines (MALs) (AACC + B’, 2n = 39) were developed from self-pollination of pentaploid hybrids (AABCC) that were derived from hybridization between hexaploid hybrids (AABBCC) and B. napus (AACC). The alien chromosomes of the B genome in MALs were identified by the GISH technique, by observation of the meiotic behavior of pollen mother cells (PMCs), and by B-genome-specific molecular marker analysis. Studies of the meiotic behavior of B. napus-B genome chromosome MALs at diakinesis revealed that the majority of the chromosome configuration was 19²+1¹, which indicated that the alien B genome chromosome remained univalent in most cases. The laggard-free PMCs also appeared at a lower ratio, which indicated that the B genome chromosome could be transmitted into gametes. The chromosome configurations of 20² and 19²+2¹ that appeared in double MALs (AACC+ 2 chromosomes of the B genome) indicated different homoeology between different B genome chromosomes. The paired B genome bivalent in double MALs can be normally segregated at anaphase in most cases. PMCs with multivalents were observed in all the double MAL combinations, which indicated homology of the B genome chromosomes with the A or C genome chromosomes.

New Results on Finite-time Stabilization for Stochastic Systems with Time-varying Delay

Lihua Zhang,Wenhai Qi,Yonggui Kao,Xianwen Gao,Longjiang Zhao 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.2

The paper deals with the problem of finite-time stabilization for stochastic systems with time-varying delay by defining a new criterion for finite-time stability. Firstly, by use of more appropriate Lyapunov-Krasovskii functional (LKF), the difficulties of finite-time stability confronted in system analysis and synthesis can be overcome. Then, a state feedback controller is constructed to guarantee the closed-loop system finite-time stable. New conditions for finite-time stability analysis as well as controller synthesis are established in terms of linear matrix inequality (LMI). Finally, two practical examples demonstrate the validity of the main results.