Prokaryotic expression, polyclonal antibody preparation, spatio-temporal expression profile and functional analysis of c-Myc of Helicoverpa armigera (Lepidoptera: Noctuidae) / 生物工程学报

c-Myc protein encoded by c-Myc (cellular-myelocytomatosis viral oncogene) gene regulates the related gene expression through the Wnt/β-catenin signaling pathway, and has received extensive attention in recent years. The purpose of this study was to express Helicoverpa armigera c-Myc gene (Ha-c-Myc) by using prokaryotic expression system, prepare the polyclonal antibody, examine the spatio-temporal expression profile of Ha-c-Myc, and investigate the possible function of Ha-c-Myc in regulating H. armigera sterol carrier protein-2 (SCP-2) gene expression. The Ha-c-Myc gene was amplified by PCR and cloned into a prokaryotic expression plasmid pET-32a(+). The recombinant plasmid pET-32a-Ha-c-Myc was transformed into Escherichia coli BL21. IPTG was used to induce the expression of the recombinant protein. Protein was purified by Ni2+-NTA column and used to immunize New Zealand rabbits for preparing the polyclonal antibody. The Ha-c-Myc expression levels in different developmental stages (egg, larva, prepupa, pupa, and adult) of H. armigera and different tissues (midgut, fat body, head, and epidermis) of the prepupa were determined by real-time quantitative reverse transcription PCR (qRT-PCR). Ha-c-Myc siRNA was synthesized and transfected into H. armigera Ha cells. The relative mRNA levels of Ha-c-Myc and HaSCP-2 in Ha cells were detected by qRT-PCR. Results showed that the pET-32a-Ha-c-Myc recombinant plasmid was constructed. The soluble Ha-c-Myc protein of about 65 kDa was expressed in E. coli. The polyclonal antibody was prepared. Western blotting analysis suggested that the antibody had high specificity. Enzyme linked immunosorbent assay (ELISA) showed that the titer of the antibody was high. Ha-c-Myc gene expressed at all developmental stages, with high levels in the early and late instars of larva, and the prepupal stage. Tissue expression profiles revealed that Ha-c-Myc expressed in various tissues of prepupa, with high expression level in the midgut, but low levels in the epidermis and fat body. RNAi results showed that the knockdown of Ha-c-Myc expression significantly affected transcription of HaSCP-2, leading to a 50% reduction in HaSCP-2 mRNA expression level. In conclusion, the Ha-c-Myc was expressed through a prokaryotic expression system, and the polyclonal anti-Ha-c-Myc antibody was obtained. Ha-c-Myc may promote the expression of HaSCP-2 and play an important role in the lipid metabolism of H. armigera. These results may facilitate further study on the potential role and function mechanism of Ha-c-Myc in H. armigera and provide experimental data for exploring new targets of green pesticides.

Reference genes screening and spatio-temporal expression analyses of cytochrome P450 monoxoygenase genes in Polygala tenuifolia by qRT-PCR / 中草药

Objective: To provide a suitable expression analysis of Polygala tenuifolia in different growth years and tissues, so as to select the stable internal control genes. The spatial and temporal expression of four cytochrome P450 monooxygenase genes in the above-mentioned samples was analyzed. Methods: The soluble curve and Ct value of eight candidate internal reference genes including Tubulin 1, Tubulin 2, Elongation 1, Elongation 2, Actin 1, Actin 2 and cdc-42 in different growth years (1-3 years old) and tissues (root,stem, leaf, and flower) of P. tenuifolia were obtained by real-time quantitative PCR (qRT-PCR). The expression stability of candidate reference genes was assessed by geNorm and NormFinder. Then, the qRT-PCR technique was also used to identify the temporal and spatial expression of four P450 genes including CYP709B2, CYP71AP39, CYP88A85 and CYP714E38 in P. tenuifolia. Results: The geNorm results showed that the stable internal reference genes expressed in P. tenuifolia were Tubulin 2 and Elongation 1. The NormFinder results showed that the most stable and suitable internal reference gene for expression analysis was Elongation 1. The mRNA expression levels of CYP709B2 and CYP71AP39 genes in stems and leaves (1-3 years old) were higher than that in roots and flowers. The CYP88A85 and CYP714E38 genes had got a higher mRNA expression level in roots (1-3 years old). Conclusion: Elongation 1 is suitable as an ideal internal control gene for qRT-PCR analysis of P. tenuifolia. The expression trend of P450s in roots, stems, leaves and flowers of cultivated P. tenuifolia is inconsistent.

Cloning,subcellular localization and spatio-temporal expression analysis of a flavonoid 3-O-glucosyltransferase gene( SmUF3GT) in Salvia miltiorrhiza / 中国中药杂志

The family of flavonoid 3-O-glucosyltransferase catalyzes the modification of anthocyanin from unstable-structure to stable-structure. In this study,based on homology cloning and transcriptome library,we isolated the full-length c DNA of UDP-glucose: flavonoid 3-O-glucosyltransferase( named SmUF3GT) from the flower tissues of S. miltiorrhiza. This gene was consisted of 1 353 bp open reading frames( ORF) encoding 450 amino acids. And the SmUF3GT protein was performed for the bioinformatic analysis. Our results showed that the protein was preliminary localized in the Golgi and peroxisome of cytosol,as well as plasma membrane and cell nuclear.QRT-PCR analyses indicated that SmUF3GT expressed differently in all tissues and organs but roots of S. miltiorrhiza and S. miltiorrhiza f.alba. During floral development,the expression of SmUF3GT showed a trend of rising fist and then down in purple-flower Danshen,whereas decreasing sharply fist and then slowly in white-flower Danshen. The present study provides basic information for further research on the network of synthesis and accumulation of flavonoids in S.miltiorrhiza.

Expression and function of long non-coding RNA AK046999 in the development of mouse cerebral cortex / 基础医学与临床

Objective To detect the expression and the role of the long non -coding RNA AK046999 in the development of mouse cerebral cortex.Methods 1) The AK046999 locus was obtained from the UCSC genome browser ,and the coding ability of protein was predicted by Coding Potential Calculator ; 2) The expression profile of AK046999 in the development of mouse cerebral cortex was analyzed by immunofluorescence and in situ hybridization;3)The AK046999 knockout mouse was constructed by TALEN technique and identified at the level of DNA and RNA; 4)The phenotype of knockout mouse cerebral cortex was analyzed by immunofluorescence and TUNEL assay.Results 1)AK046999 had weak coding ability and could be considered as non -coding RNA; 2)AK046999 was highly expressed in VZ /SVZ of the development of mouse cerebral cortex; 3)The AK046999 knockout mouse was successfully constructed; 4) Immunofluorescence results showed that there were no obvious changes in the markers of PAX6, TBR2 and NEUROD2 compared with the control, and apoptotic cells also had no obvious change.Conclusions The AK046999 is expressed in the cerebral cortex of developing mouse and AK046999 knockout has no effect on proliferation, differentiation and apoptosis of neural progenitor cells in the cerebral cortex .

The temporal expression patterns of the transcription factors and target genes in cardiomyocyte hypertrophy / 解放军医学杂志

Objective To investigate the temporal expression patterns of the related transcription factors and target genes in cardiomyocyte hypertrophy,and provide valuable clues for further researches on cardiomyocyte hypertrophy.Methods Isoproterenol (ISO) was used to induce ventricular myocytes hypertrophy in neonatal mice.The survival rate of cardiomyocyte was detected by CCK-8,and the average diameters and surface areas of cells were measured by computer photograph analysis system.The mRNA and protein expression levels of related genes were respectively measured by RT-PCR and Western blotting.Results The model of cardiomyocyte hypertrophy stimulated by ISO was constructed successfully.The expression levels of GATA4,MEF2C,GATA5,BNP and ANP increased 24 hours after ISO treatment,the expression levels of P300,α-MHC and TBX5 increased 12 hours after ISO treatment,and of SRF and β-MHC mRNA increased 6 hours after ISO treatment (P＜0.05).The expression levels of GATA4,α-MHC,β-MHC,SRF and P300 mRNA increased firstly,and then decreased in cardiomyocytes induced by ISO.The expression levels of GATA4,SRF,α-MHC,β-MHC and P300 mRNA were still higher than normal (P＜0.05),but of MEF2C decreased to normal (P＞0.0S) 72 hours after ISO treatment.The expression levels continuously elevated of GATA5,TBX5,ANP and BNP mRNA than that of controls (P＜0.05),while no fluctuation was found in NKX2.5 mRNA expression (P＞0.05).The expression of GATA4 protein increased,while of HEY2 protein decreased 48 hours after ISO treatment (P＜0.05).Conclusions In hypertrophic cardiomyocytes,the expression pattern of MEF2C is similar to,but the patterns of GATA5,GATA4,TBX5 and SRF are different with that in the development of heart,implying these genes are important during the process from compensatory stage to decompensation stage.The expression patterns of GATA4,MEF2C and SRF are similar to that of acetylase P300,implying the temporal expressions could be regulated by P300 in cardiomyocyte hypertrophy.

Screening of reference genes in Lonicera macranthoides and spatio-temporal expression analysis of LmAGL15 in Mads-box family / 中草药

Objective: To screen the reference genes of Lonicera macranthoides for gene expression analysis and to study the spatio-temporal expression characteristics of LmAGL15 which was a member of Mads-Box family. Methods: In this study, 18 S rRNA, Ubiquilin, Actin and Efl-β of L. macranthoides were cloned and the stabilities of the four housekeeping genes were evaluated in different positions (leaves, stems, and buds) and different periods of bud development. In addition, the spatio-temporal expression of LmAGL15 gene was analyzed. Results: 18 S rRNA was the most suitable reference gene for spatio-temporal expression analysis in L. macranthoides; The relative expression of LmAGL15 was low in leaves and stems, and that in buds was higher. Conclusion: 18 S rRNA is the most suitable reference gene in L. macranthoides. The relative expression of LmAGL15 changes significantly in leaves, stems, and buds.

Screening of reference genes in Siraitia grosvenorii and spatio-temporal expression analysis of 3-hydroxy-3-methylglutaryl coenzyme A / 中草药

Objective: To screen the reference genes of Siraitia grosvenorii for gene expression analysis, and to study the spatio-temporal expression characteristics of 3-hydroxy-3-methylglutaryl coenzyme A (HMGR) which was the key enzyme of mogroside V biosynthesis. Methods: In this study, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), microtubule associated protein (α-tubulin), actin (β-actin), and ubiquitin (UBQ5) fragments of S. grosvenorii were cloned, and the stabilities of the four housekeeping genes were evaluated in different positions (leaves, stems, and fruits) and different periods of fruit development. In addition, the spatio-temporal expression of HMGR gene was analyzed. Results: UBQ5 was the most suitable reference gene for spatio-temporal expression analysis in S. grosvenorii; The relative expression of HMGR was low in leaves, and that in stems and fruits was higher; The relative expression quantity of HMGR in fruits showed the fluctuation changes that increased firstly and then decreased, then increased and decreased again; The highest expression of HMGR was at 70 d of fruit development period, followed by 5, 30, 10, and 50 d. Conclusion: UBQ5 is the most suitable reference gene in S. grosvenorii. The relative expression of HMGR changes significantly in leaves, stems, and fruits. The relative expression quantity of HMGR in fruits shows the fluctuation changes, which is similar to synthetic accumulation pattern of mogroside V.

Localization and temporal expression of CPSIT_0271 in Chlamydia psittaci-infected cells and its stimula-tory effects on the expression of proinflammatory cytokines by THP-1 cells / 中华微生物学和免疫学杂志

Objective To study the intracellular localization and temporal expression of CPSIT_0271 in Chlamydia psittaci-infected cells; and to investigate the effects of recombinant GST-CPSIT_0271 protein on the expression of proinflammatory cytokines including IL-6, IL-1βand TNF-αby THP-1 cells.Methods The gene encoding CPSIT_0271 of Chlamydia psittaci was expressed as fusion protein ( GST-CPSIT_0271 ) in E.coli.The polyclonal antibody was prepared by immunizing BALB /c mice with the purified recombinant pro-tein.Antibody titer was determined by ELISA .Indirect immunofluorescence assay ( IFA) was performed to lo-cate the endogenous CPSIT_0271 protein in C.psittaci-infected cells .The expression characteristics of CPSIT_0271 protein were detected by Western blot in C.psittaci-infected HeLa cells at different time points .The levels of IL-6, IL-1βand TNF-αwere analyzed by ELISA after stimulating THP-1 cells with different concentrations of CPSIT_0271 protein.Results CPSIT_0271 protein was found to express in the chlamydia inclusion of C.psittaci-infected HeLa cells .The expression of CPSIT_0271 protein was detected firstly at 36 h and increased at 48 h after C.psittaci infection.The titer of anti-CPSIT_0271 specific antibody in GST-CPSIT_0271 immu-nized mice reached to 1 ∶16 000.GST-CPSIT_0271 protein increased the levels of IL-6, IL-1βand TNF-αin THP-1 cells in a dose-dependent manner in the range of 2 to 5 μg/ml.The levels of TNF-αand IL-1βreached their peaks at 24 h, and IL-6 level peaked at 48 h upon the stimulation by 5 μg/ml of GST-CPSIT_0271 pro-tein.Conclusion CPSIT_0271 expressed in inclusion bodies of Chlamydia psittaci in the infected cells , sug-gesting it might be a late expression gene .GST-CPSIT_0271 protein shows good immunogenicity and enhances the expressions of IL-6, IL-1βand TNF-αin THP-1 cells.

Temporal expression pattern of the insulin-like growth factor II and fibroblast growth factor transcripts in avian embryogenesis

In this study, the abundance of IGF-II and bFGF transcripts was estimated in the chicken embryos using the competitive RT-PCR analysis. Significant enhancements in the abundance of IGF-II mRNA were observed at stages HH1 and 5, and a new accumulation in these levels was observed at stage HH18 in comparison to the basal levels. The abundance of bFGF mRNA increased significantly at stages HH18 and 20, followed by an upregulation in the expression of these transcripts at stage HH26. These findings provided important information about the temporal expression pattern of IGF-II and bFGF transcripts in the whole chicken embryos during in ovo development.

Fatores de crescimento coordenam múltiplas vias de sinalização durante o desenvolvimento embrionário. Neste estudo, a abundância de mRNA dos genes IGF-II e bFGF foi estimada em embriões de galinha por análises de RT-PCR competitiva. Aumentos na abundância de mRNA de IGF-II foram observados nos estádios HH1, 5. Os níveis de mRNA de bFGF exibiram aumentos a partir dos estádios HH18 e 20, seguido por uma acentuada redução a níveis basais no estádio HH24 e por um segundo pico na expressão destes transcritos no estádio HH26. Tais descobertas proporcionam importantes informações sobre o padrão de expressão destes fatores de crescimento durante a embriogênese de aves