Aspergillus oryzae is a filamentous fungus classified in the group Aspergillaceae Ascomycetes. A. oryzae is an important microorganism for industrial production of enzymes and fermented food products. It secrets large quantities of proteins or enzymes into the culture medium which makes this organism appealing for the production of heterologous proteins. Recently Electric field-mediated transformation method, electroporation, has been applied to fungal transformation. It is fast, simple to handle, and avoids the use of some chemicals. The optimum conditions for A. oryzae were determined with pILJ-16 and ~0.2 x 105 protoplast cell at various field strength. The survived population of protoplasts in the electric field were ~80% of nonprotoplast cell population at 1.3 KV/cm to ~50% at 6.3 KV/cm. The electrotransformation efficiency, expressed as transformants/microgram of input DNA/population of protoplast cells, increased with the increment of the field strength up to 6.3 KV/cm. The highest value, 14.35%, was obtained at 6.3 KV/cm and 1540ohm. Some antibiotics for the dominant selectable makers were applied to A. oryzae and Tolypocladium inflatum. Whereas phleomycin was very effective on T. inflatum, hygromycin B and phleomycin were not effective on A. oryzae. Protoplasts were obtained with hemicellulase and celluclast, instead of novozyme234. More than 104 transformants/microgram of DNA with hemicellulase-treated protoplasts were obtained by using electroporation at the condition of 2,500 voltage, 1,540 ohm and 0.50 capacitance. Less than 102 transformants/microgram of DNA were obtained with Novozyme234- and celluclast-treated protoplasts.
Anti-Bacterial Agents ; Ascomycota ; Aspergillus oryzae* ; Aspergillus* ; DNA ; Electroporation ; Fungi* ; Hygromycin B ; Oryza ; Phleomycins ; Protoplasts

To construct a system of genetic transformation suitable for Rhizopus oryzae, we constructed a single-exchange vector pBS-hygro carrying hygromycin B resistance gene (hph) as its selective marker using gene splicing by overlap extension PCR (SOE PCR) technique. We introduced this recombinant vector into Rhizopus oryzae AS 3.819 by PEG/CaCl2-mediated transformation of protoplast, electroporation of protoplast and germinated spores; and we studied the effects of hydrolysis time, field strength and spore germination time on transformation frequency. We conducted quantitative real-time PCR (qPCR) assay to determine the gene copy number of ldhA integrated in the genome of R. oryzae transformants and its effect on the stability of transformants. We successfully achieved R. oryzae transformants integrated with pBS-hygro-ldhA vector. The optimal hydrolysis time for protoplast production was 140 min, and the optimal field strength of electroporation pulse for protoplast was 13 kV/cm. The optimal germination time of spores for electroporation was 2.5 h, and the optimal field strength of electroporation pulse was 14 kV/cm. The transformation frequency of method based on germinated spores was generally higher than the methods based on protoplast. The qPCR test results suggested that transformants with high copy number of integration in a certain range were relatively stable. Our results provided basis and support for metabolic regulation and genetic engineering breeding of R. oryzae.
DNA, Recombinant ; Electroporation ; Genetic Engineering ; Genetic Vectors ; Hygromycin B ; Protoplasts ; Real-Time Polymerase Chain Reaction ; Rhizopus ; genetics ; Transformation, Genetic

Current studies have shown that centromere protein F (CENPF) was overexpressed in hepatocellular carcinoma (HCC) and might be involved in the pathogenesis of HCC. Specifically, due to the very large molecular weight (358 kDa) of CENPF full length protein, only CENPF knock-down, but not overexpression models, were applied currently to explore the carcinogenicity of CENPF in HCC. Whether CENPF overexpression is a cause or an effect in HCC remains to be illustrated. We aimed to establish a CENPF overexpression cell model using CRISPR/dCas9 synergistic activation mediator (SAM) system with lentiMPHv2 and lentiSAMv2 vectors to explore the role of CENPF overexpression in HCC. Single guide RNAs (sgRNAs) that specifically identify the transcription initiation site of CENPF gene were synthesized and inserted into the lentiSAMv2 plasmid. Huh-7 and HCCLM3 cells were first transduced with lentiMPHv2 and then selected with hygromycin B. The cells were then transduced with lentiSAMv2 carrying specific sgRNA for CENPF gene, followed by blasticidin S selection. The mRNA and protein detection results of Huh-7 and HCCLM3 cells screened by hygromycin B and blasticidin S showed that the endogenous overexpression of CENPF can be induced by sgRNA1 and sgRNA4, especially by sgRNA4. By using the CRISPR/dCas9 technique, stable cell models with overexpressed CENPF were successfully constructed to explore the role of CENPF in tumorigenesis, which provides a reference for the construction of cell models overexpressing large molecular weight protein.
Humans ; Carcinoma, Hepatocellular/genetics* ; Liver Neoplasms/genetics* ; RNA, Guide, CRISPR-Cas Systems ; Clustered Regularly Interspaced Short Palindromic Repeats ; Hygromycin B

<b>OBJECTIVEb>To cooperate with the study of HBV vector, hygromycin-resistant packaging cell line was developed that allows encapsidation of plasmids into HBV particles.

<b>METHODSb>Free of packaging signal, HBV genome was inserted into plasmid pMEP4, which expresses the HBV structural proteins including core, pol and preS/S proteins. HepG2 cell lines were employed to transfect with the construct. Hygromycin selection was done at a concentration of 150 micrograms/ml in the culture medium. The hygromycin-resistant clones with the best expressions of HBsAg and HBcAg were theoretically considered as packaging cell line and propagated under the same conditions. It was infected with recombinant retrovirus vector and hen selected with G418 and hygromycin in the culture medium. The existence of recombinant HBV virion in the culture medium was examined by PCR.

<b>RESULTSb>Hygromycin-resistant HBV packaging cell line was generated, which harbored an HBV mutant whose packaging signal had been deleted. Expressions of HBsAg and HBcAg were detectable. Infected with recombinant retrovirus pRV-CP, the hygromycin-resistant packaging cell line was found to secrete mutant HBV particles and no wild-type HBV was detectable in the culture medium.

<b>CONCLUSIONb>After the packaging signal was deleted and transfected into HepG2 cell lines, the partial HBV genome lost its ability to form wild-type HBV, but conserves cis-action providing structural proteins for the packaging of the replication-defective HBV.

Cell Line ; Drug Resistance, Viral ; Genetic Vectors ; Genome, Viral ; Hepatitis B virus ; drug effects ; genetics ; Humans ; Hygromycin B ; pharmacology ; Mutation ; Plasmids ; Retroviridae ; genetics ; Transfection ; Virus Assembly

We developed pancreatic and duodenal homeobox1 (Pdx1) knockout mice to improve a compensatory hyperinsulinemia, which was induced by hyperplasia in the beta cells or Langerhans' islands, as the diabetic model mice. For targeting of Pdx1 gene by homologous recombination, ES cells derived from a 129(+Ter)/SvJclxC57BL/6JJcl hybrid mouse were electroporated and subjected to positive-negative selection with hygromycin B and ganciclovir. As these results, one of the three chimeric mice succeeded to produce the next or F1 generation. Then, the mouse fetuses were extracted from the mother's uterus and analyzed immunohistologically for the existence of a pancreas. The fetuses were analyzed at embryonic day 14.5 (E14.5) because Pdx1 knockout could not alive after birth in this study. Immunohistochemical staining revealed that 10 fetuses out of 26 did not have any PDX1 positive primordium of the pancreas and that the PDX1 expresses in both the interior and exterior regions of intestine. In particular, one the exterior of the intestine PDX1 was expressed in glands that would be expected to form the pancreas. The result of PCR genotyping with extracted DNA from the paraffin sections showed existence of 10 Pdx1-knockout mice and corresponded to results of immunostaining. Thus, we succeeded to establish a Pdx1-knockout (Pdx1-/-) mice.
Animals ; DNA ; Fetus ; Ganciclovir ; Homologous Recombination ; Hygromycin B ; Hyperinsulinism ; Hyperplasia ; Intestines* ; Islands ; Mice ; Mice, Knockout* ; Pancreas ; Paraffin ; Parturition ; Polymerase Chain Reaction ; Uterus

To generate transgenic mice in which both hygromycin (hyg) and neomycin (neo) resistance genes are expressed in murine fibroblast cells (MEFs), which are required for conditional gene knock-out and screening of drug resistant ES cell clones. To construct HygR-neoR expression vector, pTK-hygR-pA and PGK-neoR-pA were cloned into pBluescript vector. DNA fragments of tandem genes ( 4245bp ) were prepared by Kpn I and Xba I digestion and transgene was microinjected into pronucleus of zygotes to generate transgenic mice. Transgenic mice were identified by PCR and Southern blot; expression of hygR and neoR gene transcripts were detected by RT-PCR. 7 founder mice carrying hyg-neo resistant genes were obtained and 6 transgenic mouse lines were successfully established. The hygR and neoR gene transcripts were detected in the liver and/or ovary of transgenic mice from hn30, hn33, hn66 and hn67 mouse lines. In MEFs isolated from the mice of line hn66 and hn30, expression of hyg and neo resistant genes was also detectable. Transgenic mouse lines expressing two anti-drug genes have been established. The hyg and neo resistant gene transcripts were detected in the MEFs of two transgenic mouse lines.
Animals ; Cinnamates ; pharmacology ; Drug Resistance, Multiple ; genetics ; Fibroblasts ; metabolism ; Hygromycin B ; analogs & derivatives ; pharmacology ; Mice ; Mice, Transgenic ; Neomycin ; pharmacology ; Transgenes ; genetics

Human gingival fibroblasts have proven to useful as a species specific cell culture system in various system on periodontal disease and regeneration. However, their use is limited, since they are hard to obtain and lifespan is short due to replicative senescence. To overcome these disadvantages, we transfected primary human gingival fibroblasts by the E6 and E7 genes of the Human papilloma virus(HPV) 16. The full length of HPV 16 E6 and E7 was cloned from the pBR322 into BamH1 and Sal I of a pBabe vector including hygromycin B resistance. Before pBabeE6/E7 plasmid transfection, peak 8 GFP including G418 resistance was transfected into primary GF to check the transfection efficency. PBabe E6/E7 plasmid was transfected using Lipofectamine plus following manufacter's instruction into primary normal human gingival fibroblasts in 60mm dishes with FBS free DMEM. After 2 days of transfection, the cells were treated with hygromycin for 2 weeks until the transfected control cells died. The resulting hygromycin resistant colonies were pooled, and clonned, and sucessful transfection was established for immortalized gingival fibroblast cell lines. Immoralized GF cells showed stellate shape, that is similar to that of orange grains, and more rapid growth and higher proliferation than that of primary gingival fibroblasts. This cell lines overcame crisis and could be cultured over 30 subcultured, could be use for three dimentional culture, epithelial-mesenchymal interaction study.
Cell Aging ; Cell Culture Techniques ; Cell Line* ; Edible Grain ; Citrus sinensis ; Clone Cells ; Fibroblasts* ; Human papillomavirus 16 ; Humans* ; Hygromycin B ; Papilloma ; Periodontal Diseases ; Plasmids ; Regeneration ; Transfection

Since it is known that Agrobacterium tumefaciens, which has long been used to transform plants, can transfer the T-DNA to yeast Saccharomyces cerevisiae during tumourigenesis, a variety of fungi were subjected to transformation to improve their transformation frequency. In this study, I report the A. tumefaciens-mediated transformation of filamentous fungus Aspergillus niger. Transfer of the binary vector pBIN9-Hg, containing the bacterial hygromycin B phosphotransferase gene under the control of the Aspergillus nidulans trpC promoter and terminator as a selectable marker, led to the selection of 50~100 hygromycin B-resistant transformants per 1x10(7) conidia of A. niger. This efficiency is improved 10~20 fold more than reported elsewhere. In order to avoid the difficulties in selection transformant from the over-growing non-transformant, I used top agar containing 900 microg/ml of hygromycin. Genomic PCR and Southern analysis showed that all transformants contained single T-DNA insert per fungal genome. This technique offers an easier and more efficient method than that of using protoplast.
Agar ; Agrobacterium tumefaciens* ; Agrobacterium* ; Aspergillus nidulans ; Aspergillus niger* ; Aspergillus* ; Fungi* ; Genome, Fungal ; Hygromycin B ; Niger ; Polymerase Chain Reaction ; Protoplasts ; Saccharomyces cerevisiae ; Spores, Fungal ; Yeasts

In this study, we developed an efficient electroporation-mediated transformation system featuring Flammulina velutipes. The flammutoxin (ftx) gene of F. velutipes was isolated by reverse transcription-PCR. pFTXHg plasmid was constructed using the partial ftx gene (410 bp) along with the hygromycin B phosphotransferase gene (hygB) downstream of the glyceraldehydes-3-phosphate dehydrogenase (gpd) promoter. The plasmid was transformed into protoplasts of monokaryotic strain 4019-20 of F. velutipes by electroporation. High transformation efficiency was obtained with an electric-pulse of 1.25 kV/cm by using 177 transformants/microg of DNA in 1 x 107 protoplasts. PCR and Southern blot hybridization indicated that a single copy of the plasmid DNA was inserted at different locations in the F. velutipes genome by non-homologous recombination. Therefore, this transformation system could be used as a useful tool for gene function analysis of F. velutipes.
Agaricales ; Blotting, Southern ; Chimera ; Cinnamates ; Coat Protein Complex I ; DNA ; Electroporation ; Flammulina ; Fungal Proteins ; Genome ; Hygromycin B ; Mycotoxins ; Oxidoreductases ; Plasmids ; Polymerase Chain Reaction ; Protoplasts ; Recombination, Genetic ; Sprains and Strains

The alteration of T lymphocyte functions as a consequence of human immunodeficiency virus (HIV) infection is a potential target for the genetic treatment of the acquired immunodeficiency syndrome (AIDS). One approach to the gene therapy for AIDS is to block the replication of HIV-1. Tat-dependent expression of forein gene and selective infection of CD4(+) cells by retroviral vector might be useful for abrogating the production of HIV-1 from cells. As part of studies to examine the feasibility of this concept, I constructed tat(+) and tat(-) HIV-1 proviral vectors that express all HIV-1 genes except for env and/or tat gene. When tat(+) or tat(-) HIV-1 particles were used for infection of HeLa T4 cells containing the endogenous beta-galactosidase (lacZ) gene under the control of the HIV-1 promoter and transactivation response element sequences, only the tat(+) HIV-1 particles transactivated the lacZ gene expression. This activation of lacZ expression following HIV infection of Tat(-) cells that stably contained but did not express the lacZ construct was determined to be an efficient process. I also constructed simple HIV-1 vectors that express the lacZ gene in a Tat-dependent manner or the hygromycin B phosphostransferase gene (Hyg(r)) under the control of the SV40 early promoter. The Tat-dependent vector conferring the lacZ(+) phenotype was assayed by beta-gal staining after infection of Tat(+) or Tat(-) cells. The activation of lacZ expression was observed only in tat(+) cells. Another simple HIV-1 vector containing the Hyg(r) gene was used for retroviral production from HeLa cells expressing the HIV-1 env gene and infection of CD4(+) or CD4(-) cells, but Hyg(r) colony was observed only from CD4(+) cells. These results provide a rationale for the use of HIV-1 retroviral vector system in the design of gene therapy of HIV infection.
Acquired Immunodeficiency Syndrome ; beta-Galactosidase ; CD4-Positive T-Lymphocytes ; Genes, env ; Genes, tat ; Genetic Therapy ; HeLa Cells ; HIV Infections ; HIV* ; HIV-1 ; Humans* ; Hygromycin B ; Lac Operon ; Lymphocytes ; Phenotype ; Response Elements ; Transcriptional Activation ; Zidovudine