• Journal of Microbiology and Biotechnology
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• v.13 no.5
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• pp.819-822
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• 2003

Polyketides are an extensive class of secondary metabolites with diverse molecular structures and biological activities. A plasmid-based minimal polyketide synthase (PKS) expression cassette was constructed using a subset of actinorhodin (act) biosynthetic genes (actI-orfl, actI-orf2, actI-orf3, actIII, actⅦ, and actIV) from Streptomyces coelicolor, which specify the construction of an orange-fluorescent anthraquinone product aloesaponarin II, a type II polyketide compound derived from one acetyl coenzyme A and 7 malonyl coenzyme A extender units. This system was designed as an indicator pathway in S. parvulus to generate a hybrid type II polyketide compound via gene-specific replacement. The act ${\beta}-ketoacyl$ synthase unit (actI-orfl and actI-orf2) in the expression cassette was specifically replaced with oxytetracycline ${\beta}-ketoacyl$ synthase otcY-orfl and otcY-orf2). This plasmid-based hybrid PKS cassette generated a novel orange-fluorescent compound structurally different from aloesaponarin II in both S. lividans and S. parvulus. In addition, several additional distinctive blue-fluorescent compounds were detected, when this hybrid PKS cassette was expressed in S. coelicolor B78 (actI-orf2 mutant), implying that the expression of plasmid-based hybrid PKS cassette in Streptomyces species should be an efficient way of generating hybrid type II polyketide compounds.

• Cross-Cultural Studies
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• v.47
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• pp.217-240
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• 2017

This paper is based on a comparative analysis of the Korean act subject marks '-에게(한테), -로, -에' and Chinese passive marks '被[$b{\grave{e}}i$]/?[$r{\grave{a}}ng$]/叫[$ji{\grave{a}}o$]/?[$g{\check{e}}i$]'. Each distribution's aspects and characteristics were examined and corresponding relationships were analyzed by comparison of these forms. The method of this comparative analysis focused on three aspects such as tangible characteristics of the two languages, selective restrictions on the 'act subject' or 'passive subject' in the passive expression, and constraints on the use of the act subject (passive) marks in the Korean passive expression by '받다'. In this comparative analysis Korean act subject markers '-에게(한테), -로, -에' and Chinese passive markers '被/?/叫/?' are always as an adverb in passive expression in combination with the act subject. Despite this common point, some differences were revealed relative to the use of the two languages. First, we reveal that the 'act subject' and the conjoined manner follow the passive expression according to characteristics of the two languages. In addition, the act subject marks of Korean passive expressions '에게/한테, -에/로' only serve as an investigative role. They are limited only to [${\pm}animate$] of the act subject. But Chinese passive markers '被/?/叫/?' are often restricted by [${\pm}animate$] of passive subject, existence and non-existence of act subject. In the Korean passive expression by '받다', it is used as act subject marks '에게/한테, -에/로' but the Chinese passive marks are restricted by the meaning of lexical items in a sentence.

• Journal of Plant Biotechnology
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• v.40 no.1
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• pp.27-36
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• 2013

We isolated and functionally characterized a Dendrobium Actin1 (DmACT1) promoter that drives strong gene expression in the orchid genus Dendrobium. A genomic fragment containing the region 3227 bp upstream of the coding region of DmACT1 was obtained by inverse PCR. Detailed comparison of the full-length cDNA and genomic sequences revealed that DmACT1 has a 1374 bp first intron in the 5' UTR. However, the 5' flanking sequences upstream of the coding region showed no obvious sequence similarities compared to those of known promoters, including plant actin promoters. Serial deletion constructs of the 5' flanking region from the translation initiation codon were fused to the coding sequence of a GUS/luciferase fusion reporter to identify the regulatory elements necessary for promoter activity. Transient assays in the flowers of Dendrobium revealed that the 5' UTR-intron greatly enhanced promoter activity. Moreover, the DmACT1 promoter with its 5' UTR-intron yielded approximately 10-fold higher reporter activity than the rice Act1 promoter-intron. Our data suggest that the DmACT1 promoter with its 5' UTR-intron is a useful tool for strong expression of transgenes in Dendrobium orchids.

• Journal of Plant Biology
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• v.38 no.4
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• pp.365-371
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• 1995

Binary vectors, pBI-ActR1, pBI-ActF1 and pBSH-ActR1, were constructed using pGA642, the replication origin of pTi12 and the rice actin promoter. The sizes of pBI-ActR1, pBI-ActF1 and pBSH-ActR1 were 12.9 kb, 13.2 kb and 11.95 kb, respectively. These vectors containing a rice actin promoter followed by a GUS structural gene could induce stronly the expression of GUS gene in transformed rice cells. Rice explants from 3-4 day old seedlings after germinatin were cocultured with A. tumefaceins harboring pBI-ActR1, pBI-ActF1 or pBSH-ActR1, and then GUS expression in the explants was assayed. Transformation of rice explants by these binary vectors was tissue-specific, such that the meristematic regions of shoot apex, root and hypocotyl were transformed by these binary vectors.

• 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.

• Development and Reproduction
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• v.26 no.4
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• pp.165-174
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• 2022

Three proteins [myosin heavy chain (MHC), filamin-C fragment (FIL-C), and actin 2 (ACT2)] were identified in adductor muscle from diploid and triploid Pacific oysters (Crassostrea gigas) and the relationship between the condition index (CI) and mRNA expression of these genes was investigated, together with the mRNA expression of molluscan insulin-related peptide (MIP), C. gigas insulin receptor-related receptor (CIR), and insulin-like growth factor binding protein complex acid labile subunit (IGFBP-ALS). Monthly changes in the CI were similar to the changes in the tissue weight rate in both groups. ACT2 and MHC mRNA expression was statistically higher in the triploid than the diploid, while FIL-C mRNA expression was significantly higher in the diploid (p<0.05). The MIP, CIR, and IGFBP-ALS mRNA expression of the diploid oysters were all significantly higher in July than in other months (p<0.05). The MIP, CIR, and IGFBP-ALS mRNA expression in the triploid oysters was high in July, but there were no significant differences (p>0.05). Changes in the expression levels of the genes investigated in this study could be used as intrinsic indicators of the annual growth, maturity, and spawning period of cultured diploid and triploid C. gigas in Tongyeong, Korea.

• Research in Plant Disease
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• v.26 no.3
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• pp.144-158
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• 2020

Quantitative reverse transcription PCR is used for gene expression analysis as the accurate and sensitive method. To analyze quantification of gene expression changes in apple plants, 10 housekeeping genes (ACT, CKL, EF-1α, GAPDH, MDH, PDI, THFs, UBC, UBC10, and WD40) were evaluated for their stability of expression during infection by Apple stem grooving virus (ASGV) or in cold-stress apple plant buds. Five reference-gene validation programs were used to establish the order of the most stable genes for ASGV as CKL>THFs>GAPDH>ACT, and the least stable genes WD40CKL>UBC10, and the least stable genes were ACT

• Archives of Pharmacal Research
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• v.26 no.1
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• pp.53-57
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• 2003

We have found that ginsenoside Rc and Re induce c-fos in MCF-7 human breast carcinoma cells at both the mRNA and protein levels. However, neither ginsenoside activated the expression of reporter gene under the control of AP-1/TPA response elements. We have also examined the possibility that ginsenoside Rc and Re act by binding to intracellular steroid hormone receptors that act as transcriptional factors in the nucleus in inducing c-fos mRNA in MCF7 human breast carcinoma cells. However, ginsenoside Rc and Re did not bind to glucocorticoid, androgen, estrogen, or retinoic acid receptors as examined by the transcription activation of the luciferase reporter genes in CV-1 cells that were transiently transfected with the corresponding steroid hormone receptors and hormone responsive luciferase reporter plasmids. These data demonstrate that ginsenoside Rc and Re act via other transcription factors and not via estrogen receptor in c-Fos expression.

• Food Science and Preservation
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• v.15 no.1
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• pp.84-87
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• 2008

We used RT-PCR to measure housekeeping gene expression in mice fed GM and non-GM cabbage, in an effort to evaluate the risk of GM food to humans. After normalization of housekeeping gene levels, highly uniform expression may be seen in many organisms during various stages of development and under different environmental conditions. We assessed the expression of four genes in Chinese cabbage; these were Profilin, Tubulin-alpha (Tub-1), Heat-shock protein (Bchsp 17.6), and Ubiquitin conjugating enzyme (UBE). We measured the expression of four well-known housekeeping genes in mice: ${\beta}$-actin, (${\beta}$-act), ${\beta}$-2-microglobulin(B2m), Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and ${\beta}$-glucuronidase (Gus). Gene expression was measured in liver, stomach, small intestine, large intestine, kidney, and spleen of mice fed GM or non-GM cabbage. No significant expression differences were found.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.3
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• pp.383-387
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• 1999

Objective: There is increasing evidence for the expression of rat in gene in several extrapituitary sites including testis and ovary. We also have demonstrated that the local LH expression in the rat epididymis and uterus, the major accessory sex organs in male and female reproductive system, respectively. Design: The present study was undertaken to elucidate whether the gene for LH receptor is expressed in rat uterus and whether the expressions of uterine LH and its receptor are differentially regulated during estrous cycle. Presence of the transcripts for rat LH receptor in the rat uterine tissue were confirmed by touchdown reverse transcription-polymerase chain reaction (RT-PCR). Results: In $LH{\beta}$ semi-quantitative RT-PCR, the highest expression level was shown in estrus stage. The level of ill receptor transcripts was also fluctuated during estrous cycle. In ovariectomized rats (OVX + Oil), the expressions of both uterine LH and LH-R were markedly reduced when compared to those from normal rats. Supplement with estradiol $17{\beta}$ to the ovariectomized rats (OVX + $E_2$) restored the expression levels of LH and its receptor to the levels in uteri from normal rats. Conclusion: Our findings indicated that 1) LH and its receptor gene are expressed in the rat uterus from cycling rats, 2) the expression of uterine LH and its receptor is mainly, if not all, under the control of ovarian sex steroid(s). These results suggested that the uterine LH may act as a local regulator with auto and/or paracrine manner, though the posibility that the pituitary LH may act directly on the regulation of uterine functions could not be discarded.