A NAC Transcription Factor ZmNAC84 affects Pollen Development Through the Repression of ZmRbohH Expression in Maize

Aying Zhang,Qi Yang;Heping Zhang;Chen Liu;Liping Huang;Lili Zhao 한국식물학회 2018 Journal of Plant Biology Vol.61 No.6

The NAC proteins are plant-specific transcriptionfactors and widely distributed in plants. The wide functionsof NAC transcription factors were studied, but the roles ofNAC in pollen development are largely unclear. Here, wefound that ZmNAC84 played a vital role in maize pollendevelopment. ZmRbohH showed high expression in pollen. ZmNAC84 inhibited the ZmRbohH expression by directlybinding to its promoter in pollen. Moreover, phosphorylationof ZmNAC84 at Ser113 played an important role in thisprocess. These results suggest that ZmNAC84 plays anegative role in pollen development possibly via repressingthe ZmRbohH expression.

A New Control Strategy for a Three-Phase PWM Current-Source Rectifier in the Stationary Frame

Qiang Guo,Heping Liu,Yi Zhang 전력전자학회 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.4

This paper presents a novel power control strategy for PWM current-source rectifiers (CSRs) in the stationary frame based on the instantaneous power theory. In the proposed control strategy, a virtual resistance based on the capacitor voltage feedback is used to realize the active damping. In addition, the proportional resonant (PR) controller under the two-phase stationary coordinate is designed to track the ac reference current and to avoid the strong coupling brought about by the coordinate transformation. The limitations on improving steady-state performance of the PR controller is investigated and mitigated using a cascaded lead-lag compensator. In the z-domain, a straightforward procedure is developed to analyze and design the control-loop with the help of MATLAB/SISO software tools. In addition, robustness against parameter variations is analyzed. Finally, simulation and experimental results verify the proposed control scheme and design method.

Production of the Isoflavone Aglycone and Antioxidant Activities in Black Soymilk Using Fermentation with Streptococcus thermophilus S10

이미연,홍고은,Heping Zhang,양철영,한규호,Prabhat Kumar Mandal,이치호 한국식품과학회 2015 Food Science and Biotechnology Vol.24 No.2

The best starter culture for fermented black soymilk was determined. Black soymilk was fermented using Lactobacillus acidophilus ATCC 4356 (LA), Lactobacillus plantarum P8 (LP), and Streptococcus thermophilus S10 (ST). An ST single culture exhibited higher β-glucosidase activities than LAST (LA:ST=1:1, v/v), LPST (LP:ST=1:1, v/v), and LALPST (LA:LP:ST= 1:1:1, v/v) mixed cultures. The pH of fermented black soymilk was significantly (p<0.05) decreased during fermentation due to an increase in lactic acid formed by lactic acid bacteria. The β-glucosidase activity of the ST single culture was significantly (p<0.05) higher than for mixed cultures. Black soymilk fermented with ST alone showed significantly (p<0.05) more bioconversion of the isoflavone glycoside to aglycone, compared with controls. Black soymilk fermented with ST resulted in the best antioxidant effect. The ST single culture was best for production of health functional fermented black soymilk.

Why do we test multiple traits in genetic association studies?

Wensheng Zhu,,Heping Zhang 한국통계학회 2009 Journal of the Korean Statistical Society Vol.38 No.1

In studies of complex disorders such as nicotine dependence, it is common that researchers assess multiple variables related to a disorder as well as other disorders that are potentially correlated with the primary disorder of interest. In this work, we refer to those variables and disorders broadly as multiple traits. The multiple traits may or may not have a common causal genetic variant. Intuitively, it may be more powerful to accommodate multiple traits in genetic traits, but the analysis of multiple traits is generally more complicated than the analysis of a single trait. Furthermore, it is not well documented as to how much power we may potentially gain by considering multiple traits. Our aim is to enhance our understanding on this important and practical issue. We considered a variety of correlation structures between traits and the disease locus. To focus on the effect of accommodating multiple traits, we examined genetic models that are relatively simple so that we can pinpoint the factors affecting the power. We conducted simulation studies to explore the performance of testing multiple traits simultaneously and the performance of testing a single trait at a time in family-based association studies. Our simulation results demonstrated that the performance of testing multiple traits simultaneously is better than that of testing each trait individually for almost models considered. We also found that the power of association tests varies among the underlying models. The advantage of conducting a multiple traits test is minimized when some traits are influenced by the gene only through other traits; and it is maximized when there are causal relations between the traits and the gene, and among the traits themselves or when there are extraneous traits.

Rejoinder: Why do we test multiple traits in genetic association studies?

Wensheng Zhu,,Heping Zhang 한국통계학회 2009 Journal of the Korean Statistical Society Vol.38 No.1

This is a rejoinder to the discussions of ``Why do we test multiple traits in genetic association studies

A New Control Strategy for a Three-Phase PWM Current-Source Rectifier in the Stationary Frame

Guo, Qiang,Liu, Heping,Zhang, Yi The Korean Institute of Power Electronics 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.4

This paper presents a novel power control strategy for PWM current-source rectifiers (CSRs) in the stationary frame based on the instantaneous power theory. In the proposed control strategy, a virtual resistance based on the capacitor voltage feedback is used to realize the active damping. In addition, the proportional resonant (PR) controller under the two-phase stationary coordinate is designed to track the ac reference current and to avoid the strong coupling brought about by the coordinate transformation. The limitations on improving steady-state performance of the PR controller is investigated and mitigated using a cascaded lead-lag compensator. In the z-domain, a straightforward procedure is developed to analyze and design the control-loop with the help of MATLAB/SISO software tools. In addition, robustness against parameter variations is analyzed. Finally, simulation and experimental results verify the proposed control scheme and design method.

Identification of Coccoidal Bacteria in Traditional Fermented Milk Products from Mongolia, and the Fermentation Properties of the Predominant Species, Streptococcus thermophilus

Ren, Yan,Liu, Wenjun,Zhang, Heping Korean Society for Food Science of Animal Resource 2015 한국축산식품학회지 Vol.35 No.5

The objective of this study was to identify the coccoidal bacteria present in 188 samples of fermented yaks’, mares’ and cows’ milk products collected from 12 different regions in Mongolia. Furthermore, we evaluated the fermentation properties of ten selected isolates of the predominant species, Streptococcus (S.) thermophiles, during the process of milk fermentation and subsequent storage of the resulting yoghurt at 4℃. Overall, 159 isolates were obtained from 188 samples using M17 agar. These isolates were presumed to be lactic acid bacteria based on their gram-positive and catalase-negative properties, and were identified to species level using 16S rRNA gene sequence analysis. These coccoid isolates were distributed in four genera and six species: Enterococcus (E.) durans, Enterococcus (E.) faecalis, Lactococcus (Lac.) subsp. lactis, Leuconostoc (Leuc.) lactis, Leuconostoc (Leuc.) mesenteroides. subsp. mesenteroides and S. thermophilus. Among these S. thermophilus was the most common species in most samples. From evaluation of the fermentation characteristics (viable counts, pH, titratable acidity [TA]) of ten selected S. thermophilus isolates we could identify four isolates (IMAU 20246, IMAU20764, IMAU20729 and IMAU20738) that were fast acid producers. IMAU20246 produced the highest concentrations of lactic acid and formic acid. These isolates have potential as starter cultures for yoghurt production.

Identification of Coccoidal Bacteria in Traditional Fermented Milk Products from Mongolia, and the Fermentation Properties of the Predominant Species, Streptococcus thermophilus

Yan Ren,Wenjun Liu,Heping Zhang 한국축산식품학회 2015 한국축산식품학회지 Vol.35 No.5

The objective of this study was to identify the coccoidal bacteria present in 188 samples of fermented yaks’, mares’ and cows’ milk products collected from 12 different regions in Mongolia. Furthermore, we evaluated the fermentation properties of ten selected isolates of the predominant species, Streptococcus (S.) thermophiles, during the process of milk fermentation and subsequent storage of the resulting yoghurt at 4°C. Overall, 159 isolates were obtained from 188 samples using M17 agar. These isolates were presumed to be lactic acid bacteria based on their gram-positive and catalase-negative properties, and were identified to species level using 16S rRNA gene sequence analysis. These coccoid isolates were distributed in four genera and six species: Enterococcus (E.) durans, Enterococcus (E.) faecalis, Lactococcus (Lac.) subsp. lactis, Leuconostoc (Leuc.) lactis, Leuconostoc (Leuc.) mesenteroides. subsp. mesenteroides and S. thermophilus. Among these S. thermophilus was the most common species in most samples. From evaluation of the fermentation characteristics (viable counts, pH, titratable acidity [TA]) of ten selected S. thermophilus isolates we could identify four isolates (IMAU 20246, IMAU20764, IMAU20729 and IMAU20738) that were fast acid producers. IMAU20246 produced the highest concentrations of lactic acid and formic acid. These isolates have potential as starter cultures for yoghurt production.

Molecular cloning and expression analysis of annexin A2 gene in sika deer antler tip

Xia, Yanling,Qu, Haomiao,Lu, Binshan,Zhang, Qiang,Li, Heping Asian Australasian Association of Animal Productio 2018 Animal Bioscience Vol.31 No.4

Objective: Molecular cloning and bioinformatics analysis of annexin A2 (ANXA2) gene in sika deer antler tip were conducted. The role of ANXA2 gene in the growth and development of the antler were analyzed initially. Methods: The reverse transcriptase polymerase chain reaction (RT-PCR) was used to clone the cDNA sequence of the ANXA2 gene from antler tip of sika deer (Cervus Nippon hortulorum) and the bioinformatics methods were applied to analyze the amino acid sequence of Anxa2 protein. The mRNA expression levels of the ANXA2 gene in different growth stages were examined by real time reverse transcriptase polymerase chain reaction (real time RT-PCR). Results: The nucleotide sequence analysis revealed an open reading frame of 1,020 bp encoding 339 amino acids long protein of calculated molecular weight 38.6 kDa and isoelectric point 6.09. Homologous sequence alignment and phylogenetic analysis indicated that the Anxa2 mature protein of sika deer had the closest genetic distance with Cervus elaphus and Bos mutus. Real time RT-PCR results showed that the gene had differential expression levels in different growth stages, and the expression level of the ANXA2 gene was the highest at metaphase (rapid growing period). Conclusion: ANXA2 gene may promote the cell proliferation, and the finding suggested Anxa2 as an important candidate for regulating the growth and development of deer antler.

Yeast Surface Display of Capsid Protein VP7 of Grass Carp Reovirus: Fundamental Investigation for the Development of Vaccine Against Hemorrhagic Disease

( Shaoxiang Luo ),( Liming Yan ),( Xiaohua Zhang ),( Li Yuan ),( Qin Fang ),( Yong An Zhang ),( Heping Dai ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.12

VP7, an outer capsid protein of grass carp reovirus (GCRV), was expressed and displayed on the surface of Saccharomyces cerevisiae for developing an efficient vaccine against hemorrhagic disease of grass carp. The result of flow cytometry analysis indicated that protein VP7 could be displayed on the surface of yeast cells after inducing with galactose. The expression of VP7 was confirmed by western blot analysis and further visualized with confocal microscopy. The specific antibodies against VP7 generated from mice were detectable from all immune groups except the control group, which was immunized with untransformed yeast cells. The displaying VP7 on glycosylation-deficient strain EBYΔMnn9 was detected to induce a relatively low level of specific antibody amongst the three strains. However, the antiserum of EBYΔM9-VP7 showed relative high capacity to neutralize GCRV. Further neutralization testing assays indicated that the neutralizing ability of antiserum of the EBYΔM9-VP7 group appeared concentration dependent, and could be up to 66.7% when the antiserum was diluted to 1:50. This result indicates that appropriate gene modification of glycosylation in a yeast strain has essential effect on the immunogenicity of a yeast-based vaccine.