• Journal of Plant Biology
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• v.37 no.3
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• pp.371-380
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• 1994

To determine the patterns and the levels of expression of the cauliflower mosaic virus (CaMV 35S) promoter and the rice actin 1 (Act1) promoter in rice, transgenic rice plants containing CaMV 35S-$\beta$-glucuronidase (GUS) and Act1-GUS constructs were generated and examined by fluorometric and histochemical analyses. The fluorometric analysis of stably transformed calluses showed that the activity of the rice Act1 promoter was stronger than that of the CaMV 35S promoter in rice cells. In a histochemcial study of the transgenic rices, it was shown that the GUS activity directed by the CaMV 35S promoter was localized mainly in parenchymal cells of vascular tissues of leaves and roots and mesophyll cells of leaves. These results are similar to those of potato, a dicot plant. In contrast, rice plant transformed with Act1-GUS fusion construct revealed strong GUS activity in parenchymal cells of vascular tissue, mesophyll cells, epidermal cells, bulliform cells, guard subsidiary cells of leaves and most cells of the root, suggesting that the rice Act1 promoter is more constitutive than the CaMV 35S promoter. It was also confirmed that in both types of transgenic rice little or no staining was localized in metaxylen tracheary elements of vascular tissue from leaves or roots. These results indicate that the rice Act1 promoter can be utilized more successfully for expression of a variety of foreign gene in rice than the CaMV 35S promoter.

• Horticultural Science & Technology
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• v.18 no.5
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• pp.594-598
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• 2000

This study was carried out to investigate the tissue-specific expression of ${\beta}$-glucuronidase (gus) gene driven by endosperm-specific promoter (Z4 promoter) in the transgenic tobacco and to find out inheritance pattern of transgene to the next generation. Tobacco (Nicotiana tabaccum cv. Havana SR1) was transformed with Agrobacterium tumerfaciens LBA4404 harboring BV3 construct containing gus gene driven by Z4 promoter and a kanamycin resistant gene. Seven hundred bp PCR products, indicating the presence of npt II gene, were found in the all eight transformants by PCR analysis using nptII primers. To study the expression pattern of the two different kind of promoters, leaf disks of the Z4pro-gus-transformed plants and 35Spro-gus-transformed plants were analyzed histochemically for gus activity. As a result, leaf disks of Z4pro-gus-transformed plants showed very weak and partial positive gus activity. In contrast, leaf disks of 35Spro-gus-transformed plants showed relatively strong positive gus activity. To investigate the expressed position of Z4 promoter, seeds from Z4pro-gus-transformed plants and 35Spro-gus-transformed plants were analyzed histochemically for gus activity. Z4pro-gus-transformed seeds showed positive gus activity restricted to the endosperm. However, the blue-colored product in 35Spro-gus-transformed seeds was observed in all the area including endosperm. Kanamycin resistance assay showed that transgenes were stably inherited to next generation in all lines.

• Microbiology and Biotechnology Letters
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• v.31 no.2
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• pp.111-116
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• 2003

The xylA gene of Bacillus stearothermophilus No. 236 encoding $\beta$-xylosidase was cloned and sequenced previously. The transcriptional start site of the xylA gene cloned in E. coli was identified to be the guanine (G) by primer extension analysis. This supports that the expression of xylA gene is also directed in the E. coli cells by the previously determined transcription initiation signals, -10 sequence (CATAAT) and -35 sequence (TTGTTA) separated by 12 bp. To increase the expression of $\beta$-xylosidase, firstly the spacer region of xylA promoter was extended from 12 to 17 bp, and then the -10 and -35 elements were converted into their respective consensus sequences. The mutant promoters thus obtained were tested for their activities in both the E. coli and B. subtilis host cells. The change of the length of the spacer region from 12 to 17 bp resulted in a 1.6- and 2.5-fold increase in promoter strength in comparison with the wild type promoter in E. coli and B. subtilis cells, respectively. Also, strength of the promoter with the fourth T to A transversion on its -35 element increased in the transcription level by about 35 times compared with that of wild-type promoter. However, surprisingly the 5' end C-to-T transition of the -10 hexamer showed a 5- to 15-fold reduction in $\beta$-xylosidase activity in both E. coli and B. subtilis. Together, the present data demonstrated that the 5' end nucleotide C of the -10 sequence CATAAT and the fourth nucleotide A of the -35 hexamer are two most critical nucleotides for the promoter activity in the context of the xylA promoter.

• The Plant Pathology Journal
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• v.20 no.2
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• pp.158-163
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• 2004

Chlorella is a eukaryotic microalgae which shares metabolic pathways with higher plants. These charac-teristics make chlorella a potential candidate for eukaryotic overexpression systems. Recently, a foreign flounder growth hormone gene was stably introduced and expressed in transformed Chlorella ellipsoidea by using a modified plant transformation vector that contains cauliflower mosaic virus (CaMV) 35S pro-moter and the phleomycin resistant Sh ble gene as a selection marker. In this study, this same vector was modified by incorporating a promoter and a 3' UTR region of the 33kDa peptide gene from a chlorella virus that was isolated in our laboratory. The 33kDa gene promoter was used to replace the 35S promoter and the 3' UTR was introduced to separate the target gene and downstream Sh ble gene. Three different chlorella transformation vectors containing human erythropoietin (EPO) gene were constructed. The mp335EPO vector consists of a promoter from the 33kDa peptide gene, whereas the mp3353EPO vector contains the same promoter from the 33kDa peptide gene and its 3' UTR. The mp35S33pEPO vector contains the 35S promoter and the 3' UTR from the 33 kDa peptide gene. There was no significant difference in the expression levels of EPO protein in chlorella cells transformed with either of three of the transformation vectors. These data indicate that the promoters from the chlorella virus are comparable to the most common CaMV 35S promoter. Furthermore, these data suggest that other promoters from this virus can be used in future construction of chlorella transformation system for higher expression of target proteins.

• Journal of Plant Biology
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• v.37 no.1
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• pp.17-25
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• 1994

Two potato (Solanum tuberosum L.) cultivars were transformed by Agrobacterium tumefaciens harboring cauliflower mosaic virus (CaMV) 35S promoter and $\beta$-glucuronidase (GUS) gene. Expression patterns of the CaMV 35S promoter according to tissue types and developmental stages, and genetic stability of GUS gene were investigated in the clonal progenies of transgenic potatoes. Kanamycin-resistant shoot emerged from tuber disc after 4 weeks of culture, and root was induced 6 weeks after culture on the selection medium. Shooting frequency of cvs. Superior and Dejima were 43% and 27%, respectively. Mature transformants and their clonal progenies showed no phenotypical abnormality. GUS activity was expressed primarily at parenchymatous cells of phloem tissue around the vascular cambium in the stem and root, and higher activity was found at the apical meristem of shoot, root and adventious shoot bud. GUS activity was higher at tubers of young explants than at stored tubers. These facts indicate that expression level of the CaMV 35S promoter differed according to tissue types and developmental stages of the organs. The GUS gene was stably inherited to each clonal progeny and normally expressed.

• Plant Biotechnology Reports
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• v.3 no.4
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• pp.325-331
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• 2009

To efficiently express a gene of interest in transgenic plants, the choice of promoter is a crucial factor as it directly affects the expression of the transgene that will yield the desired phenotype. The Arabidopsis ${\beta}-carotene$ hydroxylase 1 gene (AtBch1) shows constitutive and ubiquitous expression and was thus selected as one of best candidates for constitutive promoter analysis by both in silico northern blotting and semi-quantitative RT-PCR analysis. To investigate AtBch1 promoter activity, the 1,981-bp 5'-upstream region of this gene was fused with ${\beta}-glucuronidase$ (GUS) and transformed into Arabidopsis. Through the molecular characterization of transgenic leaf tissues, the AtBch1 promoter generated strong activity that drives 1.8- and 2-fold higher GUS expression than the cauliflower mosaic virus 35S (35S) promoter at the transcriptional and translational levels, respectively. Furthermore, the GUS enzyme activity driven by the AtBch1 promoter was 2.8-fold higher than that produced by the 35S promoter. By histochemical GUS staining, the ubiquitous expression of the AtBch1 promoter was observed in all tissues of Arabidopsis. Semi-quantitative RT-PCR analysis with different tissues further showed that this promoter serves as a strong constitutive driver of transgene expression in dicot plants.

• Journal of Plant Biotechnology
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• v.29 no.4
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• pp.229-233
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• 2002

Ferritin is ubiquitous in bacteria, animals and plants. Ferritin is thought to play two main roles in living cells to provide iron for the synthesis of iron protein such as ferretoxin and cytochromes and to prevent damage from radicals produced by iron/dioxygen interaction. To enhance the resistance of potato to Erwinia carotovora, the soybean ferritin gene was introduced into the potato either under CaMV 35S or hsr203J promoter. Potato transgenic plants were screened by PCR analysis using specific primers to the ferritin gene. Expression of ferritin gene under CaMV 35S and hsr203J promoter in potato transgenic plants was confirmed by northern blot analysis. hsr203J promoter known to pathogen inducible in tobacco drives the induction upon Phytophthora infestan in potato and the transcript level of ferritin gene was extremely high after 24 hours post inoculation. One of transformants under CaMV 35S promoter was increased 2.5 fold than untransformant. Each one of transgenic potato containing gene promoter CaMV 35S and hsr203J-ferrtin fusion exhibited tolerance against potato soft rot.

• KSBB Journal
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• v.7 no.3
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• pp.155-160
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• 1992

To improve the nutritional quality of plant proteins, a synthetic gene, called HEAAE (high essential amino acid encoding)-DNA, was introduced and expressed in tobacco plants. The synthetic gene, which is 292 basepair-long, codes for a protein composed of about 80% essential amino acids. To improve its expression level in plants, Cauliflower Mosaic Virus (CaMV) 355 and CaMV duplicate 35S promoters which are known as strong promoters were used with Nopaline Synthase promoter as a control. Transformed and regenerated tobacco plants were subject to analysis for introduction and expression of this gene. Integration of the gene into the plant genome and its expression into mRNAs and its proteins have been demonstrated using Southern, northern blot analysis and amino acid analysis. The differences of expression levels among CaMV duplicate 35S, CaMV 35S and Nopaline Synthase promoters are significant in term of mRNAs, but not in terms of proteins.

• Journal of Plant Biotechnology
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• v.2 no.3
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• pp.135-142
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• 2000

The activity of promoter sequences was evaluated in garlic cells using the $\beta$-glucuronidase (GUS) gene as a reporter. Histochemical GUS assay indicated transient GUS activity in leaf, callus and root cells 48 hours after particle bombardment transformation. Quantitative fluorometric assays in extracts of transformed leaves demonstrated that the CsVMV promoter induced the highest level of gene expression, which was, on average, ten fold the level induced by CaMV35S and by the Arabidopsis Act2 promoters and two fold the level expression observed with a construct containing a double CaMV35S plus the untranslated leader sequence from AMV. No activity or very low levels were observed when cells were transformed with plasmids rontaining the typical monocot promoters, Actl, from rice or the Ubi-1, from maize. The green fluorescent protein (GFP) was also tested as a marker gene for garlic transformation. Intense fluorescence was observed in leaf, callus and root cells transformed with a construct containing the gfp gene under control of the CaMV35 Promoter. No fluorescence was detected when the gfp was under control of the Ubi-1 promoter.

• Journal of Plant Biology
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• v.35 no.3
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• pp.237-245
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• 1992

To understand the properties of the cauliflower mosaic virus (CaMV) 35S promoter and the effect of the deleted maize alcohol dehydrogenase I-S (Adhl-S) intron 1 on the expression of the CaMV $35S{\beta}-glucuronidase$ (GUS) gene in potato (Solanum tuberosum L. cv. Superior), we constructed a chimeric gene and transferred it into potato with Agrobacterium tumefaciens mediated method. The pLS201, a gene transfer vector of 17.7 kilobase pairs, was composed of the CaMV 35S promoter, the 249 base pairs of deleted maize Adhl-S intron 1, the GUS reporter gene, and the kanamycin resistance gene as a selectable marker for transformation. The GUS activity was examined by histochemical and spectrophotometric assay in transformed potato plants. The GUS activity was found primarily around the vascular tissue cells in stem and root. In the spectorophotometric assay, the level of GUS activity of transgenic potato transformed with CaMV 35S/249 bp of intron 1 fragment-GUS (pLS201) was compared with that of potato transformed with CaMV 35S-GUS (pBI121). The quantitative spectrophotometric assay showed that the level of GUS activity in potato transformed with pLS201 was higher in leaf, stem and root by 30-, 34- and 42-fold, respectively than those in potato transformed with pBI121. This results indicate that the inclusion of the deleted maize Adhl-S intron 1 resulted in increament of the GUS gene expression in transgenic potato.potato.