• The Korean Journal of Nuclear Medicine
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• v.34 no.1
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• pp.1-9
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• 2000

The rapid progress of molecular genetic methods over the past two decades has necessitated the development of methods to detect and quantify genetic activity within living bodies. Reporter genes provide a rapid and convenient tool to monitor gene expression by yielding a readily measurable phenotype upon expression when introduced into a biological system. Conventional reporter systems, however, are limited in their usefulness for in vivo experiments or human gene therapy because of its invasive nature which requires cell damage before assays can be performed. This offers an unique opportunity for nuclear imaging techniques to develope a novel method for imaging both the location and amount of gene expression noninvasively. Current developments to achieve this goal rely on utilizing either reporter enzymes that accumulate radiolabeled substrates or reporter receptors that bind specific radioligands. This overview includes a brief introduction to the background for such research, a summary of published results, and an outlook for future directions.

• BMB Reports
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• v.43 no.7
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• pp.451-460
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• 2010

Starting with the first publication of lacZ gene fusion in 1980, reporter genes have just entered their fourth decade. Initial studies relied on the simple fusion of a promoter or gene with a particular reporter gene of interest. Such constructs were then used to determine the promoter activity under specific conditions or within a given cell or organ. Although this protocol was, and still is, very effective, current research shows a paradigm shift has occurred in the use of reporter systems. With the advent of innovative cloning and synthetic biology techniques and microfluidic/nanodroplet systems, reporter genes and their proteins are now finding themselves used in increasingly intricate and novel applications. For example, researchers have used fluorescent proteins to study biofilm formation and discovered that microchannels develop within the biofilm. Furthermore, there has recently been a "fusion" of art and science; through the construction of genetic circuits and regulatory systems, researchers are using bacteria to "paint" pictures based upon external stimuli. As such, this review will discuss the past and current trends in reporter gene applications as well as some exciting potential applications and models that are being developed based upon these remarkable proteins.

• The Korean Journal of Nuclear Medicine
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• v.38 no.2
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• pp.143-151
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• 2004

Recent progress in the development of non-invasive imaging technologies continues to strengthen the role of molecular imaging biological research. These tools have been validated recently in variety of research models, and have been shown to provide continuous quantitative monitoring of the location(s), magnitude, and time-variation of gene expression. This article reviews the principles, characteristics, categories and the use of radionuclide reporter gene imaging technologies as they have been used in imaging cell trafficking, imaging gene therapy, imaging endogenous gene expression and imaging molecular interactions. The studios published to date demonstrate that reporter gene imaging technologies will help to accelerate pre-clinical model validation as well as allow for clinical monitoring of human diseases.

• Reproductive and Developmental Biology
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• v.32 no.1
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• pp.21-25
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• 2008

Bone marrow mesenchymal stem cells (BMMSCs) have the capacity for self-renewal and differentiation into a variety of cell types. They represent an attractive source of cells for gene and cell therapy. The purpose of this study is to direct the specific expression of the DsRed reporter gene in $Sca-1^+$ BMMSCs differentiated into a cardiomyogenic lineage. We constructed the prMLC-2v-DsRed vector expressing DsRed under the control of the 309 tp fragment of the rat MLC-2v 5'-flanking region. The specific expression of the DsRed reporter gene under the transcriptional control of the 309 bp fragment of the rat MLC-2v promoter was tested in 5-azacytidine healed-$Sca-1^+$ BMMSCs over 2 weeks after the prMLC-2v-DsRed transfection. The prMLC-2v-DsRed was specifically expressed in the $Sca-1^+$ BMMSCs with cardiomyogenic lineage differentiation and it demonstrates that the 309 bp sequences of the rat MLC-2v 5'-flanking region is sufficient to confer cardiac specific expression on a DsRed reporter gene. The cardiac-specific promoter-driven reporter vector provides an important tool for the study of stem cell differentiation and cell replacement therapy in ischemic cardiomyopathy.

• Journal of Microbiology
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• v.38 no.3
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• pp.183-186
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• 2000

Several types of bioluminescent reporter strains have been developed for the detection and monitoring of pollutant aromatics contaminating the environment. In this study, a bioluminescent reporter strain, E. coli SHP3, was constructed by fusing the luc gene of firefly luciferase with the promoter of pcbC responsible for the meta-cleavage of aromatic hydrocarbons. the bioluminescence expressed by the luc gene in the reporter was well triggered by the promoter when it was exposed to 2,3-dihydroxybiphenyI (2,3-DHBP) at 0.5 to 1 mM concentrations. The bioluminescent response was more extensive when the reporter strain was exposed to 5 mM catechol and 2 mM 4-chlorocatechol. These different types of bioluminescent responses by E. coli SHP3 appeared to be characterized by the nature of the aromatics to stress. Since E. coli SHP3 responded to 2,3-DHBP quite sensitively, this reporter strain could be applied for detecting some catecholic pollutants.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.901-906
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• 2013

We examined the availability of the lacZ gene (${\beta}$-galactosidase gene) as a reporter of foreign gene transfer in the cysts of Artemia franciscana (A. franciscana) to conduct a risk assessment of living genetically modified organisms (LMOs) in the marine ecosystem. The LacZ gene was transferred to decapsulated cysts by particle bombardment, and its insertion and expression were assessed by means of polymerase chain reaction (PCR) and X-gal staining. X-gal staining indicated lacZ expression in all A. franciscana examined (including the control group), which exhibited not only negative but also positive PCR amplification. Endogenous ${\beta}$-galactosidase is highly active in the whole body of A. franciscana during all stages of the life cycle. Thus, the lacZ gene is unsuitable as a reporter for foreign gene transfer in A. franciscana cysts, because it is difficult to discriminate between exogenous and endogenous ${\beta}$-galactosidase activity.

• Molecules and Cells
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• v.26 no.2
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• pp.131-139
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• 2008

Expression of the seven open reading frames (ORFs) of single-stranded DNA Curtoviruses such as Beet curly top virus (BCTV) and Beet severe curly top virus (BSCTV) is driven by a bi-directional promoter. To investigate this bidirectional promoter activity with respect to viral late gene expression, transgenic Arabidopsis plants expressing a GUS reporter gene under the control of either the BCTV or BSCTV bi-directional promoter were constructed. Transgenic plants harboring constructs showed higher expression levels when the promoter of the less virulent BCTV was used than when the promoter of the more virulent BSCTV was used. In transgenic seedlings, the reporter gene constructs were expressed primarily in actively dividing tissues such as root tips and apical meristems. As the transgenic plants matured, reporter gene expression diminished but viral infection of mature transgenic plants restored reporter gene expression, particularly in transgenic plants containing BCTV virion-sense gene promoter constructs. A 30 base pair conserved late element (CLE) motif was identified that was present three times in tandem in the BCTV promoter and once in that of BSCTV. Progressive deletion of these repeats from the BCTV promoter resulted in decreased reporter gene expression, but BSCTV promoters in which one or two extra copies of this motif were inserted did not exhibit increased late gene promoter activity. These results demonstrate that Curtovirus late gene expression by virion-sense promoters depends on the developmental stage of the host plant as well as on the number of CLE motifs present in the promoter.

• The Korean Journal of Nuclear Medicine
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• v.38 no.2
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• pp.175-179
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• 2004

Molecular nuclear cardiac imaging has included Tc-99m Annexin imaging to visualize myocardial apoptosis, but is now usually associated with gene therapy and cell-based therapy. Cardiac gene therapy was not successful so far but cardiac reporter gene imaging was made possible using HSV-TK (herpes simplex virus thymidine kinase) and F-18 FHBG (fluoro-hydroxymethylbutyl guanine) or I-124 FIAU (fluoro-deoxyiodo-arabino-furanosyluracil). Gene delivery was performed by needic injection with or without catheter guidance. Tk expression did not last longer than 2 weeks in myocardium. Cell-based therapy of ischemic heart or failing heart looks promising, but biodistribution and differentiation of transplanted cells are not known. Reporter genes can be transfected to the stem/progenitor cells and cells containing these genes can be transplanted to the recipients using catheter-based purging or injection. Repeated imaging should be available and if promoter are varied to let express reporter transgenes, cellular (trans)differentiation can be studied. NIS (sodium iodide symporter) or D2R receptor genes are promising in this aspect.

• Mycobiology
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• v.46 no.4
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• pp.429-439
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• 2018

To develop a convenient promoter analysis system for fungi, a null-pigment mutant (NPG) of Aspergillus nidulans was used with the 4'-phosphopantetheinyl transferase (PPTase) gene, npgA, which restores the normal pigmentation in A. nidulans, as a new reporter gene. The functional organization of serially deleted promoter regions of the A. nidulans trpC gene and the Cryphonectria parasitica crp gene in filamentous fungi was representatively investigated to establish a novel fungal promoter assay system that depends on color complementation of the NPG mutant with the PPTase npgA gene. Several promoter regions of the trpC and crp genes were fused to the npgA gene containing the 1,034-bp open reading frame and the 966-bp 3' downstream region from the TAA, and the constructed fusions were introduced into the NPG mutant in A. nidulans to evaluate color recovery due to the transcriptional activity of the sequence elements. Serial deletion of the trpC and crp promoter regions in this PPTase reporter assay system reaffirmed results in previous reports by using the fungal transformation step without a laborious verification process. This approach suggests a more rapid and convenient system than conventional analyses for fungal gene expression studies.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.7
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• pp.885-891
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• 2004

To evaluate the feasibility of using sperm-mediated gene transfer (SMGT) for carrying foreign gene into chicken oocyte, a reporter gene, CX-EGFP, was used in this study. The reporter gene was first mixed with liposome or liposome-like compound and the mixtures were further combined with ejaculated cock spermatozoa. The spermatozoa treated with liposome and CX-EGFP mixture was subsequently coincubated with DNaseI to remove the extra DNA which insured the authenticity of positive signals. The treated sperms were then subjected to transgene (reporter gene) existence analysis and artificial insemination of laying hens. Obtained results indicated that the spermatozoa were able to take-in the foreign DNA; which was confirmed by polymerase chain reaction and Southern blot analysis. In the following experiment, fresh ejaculated sperms were mixed with CX-EGFP-liposome or CX-EGFP-liposome-like complex then used for artificial insemination of each of six laying hens. Eggs laid between day-3 and day-7 post insemination were collected. Newly hatched chicks, two out of 53 from CX-EGFP/liposome treated group and two out of 21 from CXEGFP/liposome-like treated group, were proven to be transgenic. This study suggests that SMGT is a powerful method for generating transgenic chickens.