• Title/Summary/Keyword: over-expression library

Search Result 29, Processing Time 0.021 seconds

Screening of Growth- or Development-related Genes by Using Genomic Library with Inducible Promoter in Aspergillus nidulans

  • Lee Bang-Yong;Han Sang-Yong;Choi Han Gil;Kim Jee Hyun;Han Kap-Hoon;Han Dong-Min
    • Journal of Microbiology
    • /
    • v.43 no.6
    • /
    • pp.523-528
    • /
    • 2005
  • Using the genomic library constructed at the downstream of the niiA promoter, which induces the over-expression of an inserted DNA fragment, we have attempted to screen the genes affecting growth or development by over-expression. The wild-type strain was transformed using the AMA-niiA(p) library and cultured on 1.2 M sorbitol media, in which asexual sporulation is induced, but sexual development is repressed. Over 100,000 strains transformed to $pyrG^+$ were analyzed with regard to any changes in phenotype. Consequently, seven strains were isolated for further analyses. These strains were designated NOT [niiA(p) over-expression transformants] stains. Four of the strains were of the inducible type, and the remaining strains were of the multi-copy suppression type. Two of the inducible-type strains, NOT 1 and NOT40, harbored genes which had been inserted in reverse direction, suggesting that the mutant phenotypes had been derived from an excess amount of anti-sense mRNA. Domain analyses of the deduced polypeptides from the DNA fragments rescued from the transformants revealed that NOT1, NOT40 and NOT6 harbored a LisH motif, a forkhead domain, and a $Zn(II)_2Cys_6$ binuclear zinc cluster, respectively.

Experimental development of the epigenomic library construction method to elucidate the epigenetic diversity and causal relationship between epigenome and transcriptome at a single-cell level

  • Park, Kyunghyuk;Jeon, Min Chul;Kim, Bokyung;Cha, Bukyoung;Kim, Jong-Il
    • Genomics & Informatics
    • /
    • v.20 no.1
    • /
    • pp.2.1-2.11
    • /
    • 2022
  • The method of single-cell RNA sequencing has been rapidly developed, and numerous experiments have been conducted over the past decade. Their results allow us to recognize various subpopulations and rare cell states in tissues, tumors, and immune systems that are previously unidentified, and guide us to understand fundamental biological processes that determine cell identity based on single-cell gene expression profiles. However, it is still challenging to understand the principle of comprehensive gene regulation that determines the cell fate only with transcriptome, a consequential output of the gene expression program. To elucidate the mechanisms related to the origin and maintenance of comprehensive single-cell transcriptome, we require a corresponding single-cell epigenome, which is a differentiated information of each cell with an identical genome. This review deals with the current development of single-cell epigenomic library construction methods, including multi-omics tools with crucial factors and additional requirements in the future focusing on DNA methylation, chromatin accessibility, and histone post-translational modifications. The study of cellular differentiation and the disease occurrence at a single-cell level has taken the first step with single-cell transcriptome and is now taking the next step with single-cell epigenome.

A STUDY OF APIN-PROTEIN INTERACTIONS USING PROTEIN MICROARRAY (Protein microarray를 이용한 APin-단백질의 상호작용에 관한 연구)

  • Park, Joo-Cheol;Park, Sun-Hwa;Kim, Heung-Joong;Park, Jong-Tae;Youn, Seong-Ho;Kim, Ji-Woong;Lee, Tae-Yeon;Son, Ho-Hyun
    • Restorative Dentistry and Endodontics
    • /
    • v.32 no.5
    • /
    • pp.459-468
    • /
    • 2007
  • Protein microarray or protein chips is potentially powerful tools for analysis of protein-protein interactions. APin cDNA was previously identified and cloned from a rat odontoblast cDNA library. The purpose of this study was to investigate the APin-protein interactions during ameloblast differentiation. Protein microarray was carried with recombinant APin protein and MEF2, Aurora kinase A, BMPR-IB and EF-hand calcium binding protein were selected among 74 interacting proteins. Immortalized ameloblast cells (ALCs) were transfected with pCMV-APin construct and U6-APin siRNA construct. After transfection, the expression of the mRNAs for four proteins selected by protein micoarrays were assessed by RT-PCR. The results were as follows: 1. APin expression was increased and decreased markedly after its over-expression and inactivation, respectively. 2. Over-expression of the APin in the ALCs markedly down-regulated the expression of MEF2 and Aurora kinase A, whereas their expression remained unchanged by its inactivation. 3. Expression of BMPR-IB and EF-hand calcium binding protein were markedly increased by the over-expression of the APin in the ALCs, whereas expression of BMPR-IB remained unchanged and expression of EF-hand calcium binding protein was markedly decreased by its inactivation. These results suggest that APin plays an important role in ameloblast differentiation and mineralization by regulating the expression of MEF2, Aurora kinase A, BMPR-IB and EF-hand calcium binding protein.

Antibody Engineering

  • Hong, Hyo-Jeong;Kim, Sun-Taek
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • v.7 no.3
    • /
    • pp.150-154
    • /
    • 2002
  • Monoclonal antibodies (Mabs) have been used as diagnostic and analytical reagents since hybridoma technology was invented in 1975. In recent years, antibodies have become increasingly accepted as therapeutics for human diseases, particularly for cancer, viral infection and autoimmune disorders. An indication of the emerging significance of antibody-based therapeutics is that over a third of the proteins currently undergoing clinical trials in the United States are antibodies. Until the late 1980's, antibody technology relied primarily on animal immunization and the expression of engineered antibodies. However, the development of methods for the expression of antibody fragments in bacteria and powerful techniques for screening combinatorial libraries, together with the accumulating structure-function data base of antibodies, have opened unlimited opportunities for the engineering of antibodies with tailor-made properties for specific applications. Antibodies of low immunogenicity, suitable for human therapy and in vivo diagnosis, can now be developed with relative ease. Here, antibody structure-function and antibody engineering technologies are described.

Surface expression of TTYH2 is attenuated by direct interaction with β-COP

  • Ryu, Jiwon;Kim, Dong-Gyu;Lee, Young-Sun;Bae, Yeonju;Kim, Ajung;Park, Nammi;Hwang, Eun Mi;Park, Jae-Yong
    • BMB Reports
    • /
    • v.52 no.7
    • /
    • pp.445-450
    • /
    • 2019
  • TTYH2 is a calcium-activated, inwardly rectifying anion channel that has been shown to be related to renal cancer and colon cancer. Based on the topological prediction, TTYH2 protein has five transmembrane domains with the extracellular N-terminus and the cytoplasmic C-terminus. In the present study, we identified a vesicle transport protein, ${\beta}$-COP, as a novel specific binding partner of TTYH2 by yeast two-hybrid screening using a human brain cDNA library with the C-terminal region of TTYH2 (TTYH2-C) as a bait. Using in vitro and in vivo binding assays, we confirmed the protein-protein interactions between TTYH2 and ${\beta}$-COP. We also found that the surface expression and activity of TTYH2 were decreased by co-expression with ${\beta}$-COP in the heterologous expression system. In addition, ${\beta}$-COP associated with TTYH2 in a native condition at a human colon cancer cell line, LoVo cells. The over-expression of ${\beta}$-COP in the LoVo cells led to a dramatic decrease in the surface expression and activity of endogenous TTYH2. Collectively, these data suggested that ${\beta}$-COP plays a critical role in the trafficking of the TTYH2 channel to the plasma membrane.

Molecular characterization of BrRZFPs genes encoding C3HC4 type RING zinc finger protein under abiotic stress from Chinese cabbage (Brassica rapa L.)

  • Jung, Yu Jin;Lee, Kye Dong;Cho, Yong Gu;Nou, Ill Sup;Kang, Kwon Kyoo
    • Journal of Plant Biotechnology
    • /
    • v.40 no.2
    • /
    • pp.102-110
    • /
    • 2013
  • The novel BrRZFPs genes encoding C3HC4-type RING zinc finger protein were identified from FOX (full length cDNA over-expressing) library of Brassica rapa. Ten full-length cDNAs obtained from the library encode zinc-finger protein containing 346 amino acids, designated BrRZFPs. These genes were classified into four groups by phylogenic analysis showing conserved protein sequences at both termini. The tissue distribution of BrRZFPs transcription was examined by qRT-PCR revealing ubiquitous expression pattern. However, each gene was strongly expressed in the specific tissue. Transcriptional analysis showed that those acquired 10 genes were inducible under abiotic stresses. Likewise, the transcript of BrRZFP3 was strongly induced (~12-folds) by exogenous abscisic acid, whereas the transcripts of BrRZFP1, BrRZFP2 and BrRZFP3 were (> 9-folds) induced by cold. We suggest that these BrRZFPs that function as signal or response to abiotic stress are useful for crop improvement.

A Study on the Effects of Digital Co-Teaching on Reading Literacy (디지털 협력수업이 독서 리터러시에 미치는 효과 연구)

  • Juhyeon, Park;Bong-Suk Kang
    • Journal of the Korean Society for Library and Information Science
    • /
    • v.57 no.3
    • /
    • pp.211-230
    • /
    • 2023
  • The purpose of this study is to confirm the effect of digital co-teaching between teachers online on improving students' reading literacy. In order to achieve the purpose of the study, a pre-test was conducted on first-year high school students, and a post-test was conducted after conducting the co-teaching over two sessions. For statistical analysis, the data of 101 students with no missing values in pre- and post-tests were used. Through the OECD's PISA reading literacy evaluation framework and factor analysis, a reading literacy test tool consisting of expression, comprehension, and information literacy was developed and the degree of change in reading literacy was measured through a self-report with the tool. As a result of the analysis, it was confirmed that the digital co-teaching had a statistically significant positive effect on the expression, comprehension and information literacy of high school students. This study is meaningful in that it shows that digital co-teaching can be applied as a way to improve reading literacy in PISA organized by the OECD.

Production of Monoclonal Antibody about Specific Key Enzyme of Hyoscyamine $6{\beta}-Hydroxylase$ (H6H) in Scopolia parviflora

  • Kang, Young-Min;Jung, Hee-Young;Kang, Seung-Mi;Jin, Byung-Rae;Lee, Sang-Chul;Lee, Byung-Hyun;Choi, Myung-Suk
    • Korean Journal of Medicinal Crop Science
    • /
    • v.12 no.2
    • /
    • pp.135-140
    • /
    • 2004
  • Total RNAs were isolated from cultured roots of Scopolia parviflora, $poly(A)^+$ RNA was obtained through the mRNA purification, cDNA library of Hnh6h was constructed. Recombinant baculoviruses in Spodoptera frugiperda (Sf) cells were constructed by use of the transfer vector pBacPAK, which has the AcNPV sequence under the polyhedrin promoter. The expression vector carrying Hnh6h gene was transferred to S. parviflora and obtained transgenic hairy root lines. Our results confirmed the over expression of the H6H protein was used by anti-pBacPAK about cDNAs of S. parviflora. This study will served for production of tropane alkaloids by metabolic engineering.

Simple Purification of the Human Antimicrobial Peptide Dermcidin (MDCD-1L) by Intein-Mediated Expression in E. coli

  • Hong, In-Pyo;Kim, Yong-Seok;Choi, Shin-Geon
    • Journal of Microbiology and Biotechnology
    • /
    • v.20 no.2
    • /
    • pp.350-355
    • /
    • 2010
  • Among human antimicrobial peptides (hAMPs), DCD-1L has a broad spectrum of antimicrobial activity over a wide pH range and in high salt concentrations. It offers a promising alternative to conventional antibiotics. The 458-bp-long dermcidin cDNA was amplified by PCR using a human fetal cDNA library as a template. The 147-bp fragment of the MDCD-1L gene encoding an additional methionine residue was subcloned into the pTYB11 vector. Recombinant MDCD-1L was expressed as an intein fusion protein in E. coli, and then purified by affinity chromatography using chitin beads. A small peptide with a molecular mass of about 5 kDa was detected by tricine gel electrophoresis. The recombinant MDCD-1L peptide was purified from the gel and its amino acid sequence was determined by nanoLC-ESI-MS/MS analysis. The initiating amino acid, methionine, remained attached to the N-terminal region of recombinant MDCD-1L. Purified MDCD-1L showed antimicrobial activity against a Micrococcus luteus test strain.

Identification and Characterization of pH-Regulated Genes in Saccharomyces cerevisiae

  • Hong, Sung-Ki;Choi, Eui-Yul
    • Journal of Microbiology
    • /
    • v.34 no.4
    • /
    • pp.327-333
    • /
    • 1996
  • Yeast, like many other microbes, encounters large variations in ambient pH in their natural environments. Microorganisms capable of growing over a wide pH range require a versatile, efficient pH homeostatic mechanism protecting intracellular processes against extremes of pH. In several organisms, fusions to the bacterial lacZ gene have been extremely useful for the identification of genes expressed at different time during the life cycle or under different growth conditions. In this study, using the lacZ gene screening system, we surveyed a large number of yeast strains with lacZ insertion to identify genes regulated by pH. A yeast genomic library was constructed and inserted with lacZ by a shuttle mutagenesis procedure. The yeast transformants were individually picked up with a toothpick, replica-plated, and grown in alkaline pH medium. Among the 35,000 colonies screened, 10 candidate strains were identified initially by the $\beta$-gal assay. We finally confirmed two yeast strains carrying the genes whose expression are strictly dependent on pH of growth medium. One of the fusions showing a 10-fold induction in expression level in response to alkali pH was selected and further characterized. The pH-regulated gene was cloned by inverse PCR and a partial sequence of the gene was determined. Identification and characterization of the gene is currently under investigation.

  • PDF