• Biomolecules & Therapeutics
• /
• v.13 no.4
• /
• pp.227-231
• /
• 2005

The estrogen receptor (ER) is activated and degraded by estrogen. We have examined ER downregulation and activation under hypoxia mimetic conditions. Cobalt chloride induced ER downregulation at 24 h of treatment. This degradation involved hypoxia-inducible factor-1$\alpha$ (HIF-1$\alpha$) as examined by using a constitutively active form of HIF-1$\alpha$, HIF-1$\alpha$/VP16, constructed by replacing the transactivation domain of HIF-1$\alpha$ with that of VP16. Western blot analysis revealed that E2-induced ER downregulation was observed within ${\~}6h$, whereas HIF-1$\alpha$/VP16-induced ER degradation was observed within 12${\~}$20h. HIF-1$\alpha$/VP16 activated the transcription of estrogen-responsive reporter gene in the absence of estrogen. These results suggest that ER downregulation and activation under hypoxia maybe mediated in part by a HIP-1$\alpha$ expression.

• Journal of Plant Biotechnology
• /
• v.42 no.2
• /
• pp.93-103
• /
• 2015

The isolation, cloning, and characterization of an R2R3-MYB transcription factor gene (MtMYB70) from the model legume Medicago truncatula is reported. MtMYB70 consists of a 768-bp coding sequence corresponding to 255 amino acids. Sequence alignment revealed that MtMYB70 cDNA contains conserved R2R3-type MYB domains with highly divergent C terminal regions. MtMYB70 was found to have relatively low sequence homology with known R2R3-MYB genes. Phylogenetic analysis placed the R2R3-MYB domain of MtMYB70 closest to PtMYB1, a known activator of lignin biosynthesis. Overexpression of MtMYB70 under the control of the 35S promoter in transgenic poplar did not cause a significant difference in total lignin content relative to the control, but glucan content was significantly increased in transgenic poplar. Therefore, MtMYB70 might have regulatory role in the biosynthesis of cell wall structural carbohydrates.

• Korean Journal of Environmental Biology
• /
• v.39 no.2
• /
• pp.160-168
• /
• 2021

Doublesex and mab-3 related transcription factor(dmrt) play crucial roles in sex determination and sex differentiation in vertebrates and invertebrates. Although dmrt genes have been identified in vertebrates, little is known about aquatic invertebrates. In this study, two dmrt genes, namely, Dc_dmrt93B and Dc_dmrt99B, were identified from brackish water flea, Diaphanosoma celebensis. Transcriptional changes were observed in the dmrt genes when the flea was exposed to bisphenol(BP), an endocrine disruptor. Sequence and phylogenetic analyses showed that both dmrt genes contained two conserved domains, namely, DM and DMA, closely clustered with those of Daphnia spp. Additionally, a significant increase in the Dc_dmrt99B mRNA expression level was observed upon exposure to intermediate concentrations of BP (bisphenol A>bisphenol S=bisphenol F, p<0.05), while the expression of Dc_dmrt93B mRNA was slightly modulated. These findings imply that the two dmrt genes may be involved in sex differentiation of D. celebensis. Furthermore, it was found that the ability of BP to modulate dmrt genes could affect development and reproduction. This study provides a basis for understanding the function of the dmrt genes and the molecular mode of action of BP in small crustaceans.

• Journal of Photoscience
• /
• v.7 no.2
• /
• pp.73-78
• /
• 2000

To analyze molecular traits determining pigmentation between Pharbitis nill violet and white, Amplified Fragment Length Polymorphism(AFLP) and Differential Display Reverse Transcription(DDRT) experiments were carried out with either genomic DNAs or total RNAs isolated from both plants. Results of AFLP experiment in combination of 8 EcoRⅠ primers with 6 MseⅠ primers showed 41 violet-and 60 white-specific DNA bands. In the subsequent experiment, 22 violet-and 22 white-specific DNA fragments were amplified by PCR with DNAs eluted. The sizes of the fragments range from 200 to 600bp. DDRT using total RNA produced 19 violet-and 17 white-specific cDNA fragments, ranging from 200 to 600bp. The fragments obtained by both AFLP and DDRT had been cloned into pGEM T-easy vector, amplified and subjected to the nucleotide sequence analyses. As a result of Blast sequence analysis, most of them sequenced up to date showed no similarity to any Known gene, while few has similarity to known animal or plant genes. An AFLP clone V6, for example, has a strong sequence similarity to the human transcription factor LZIP-alpha mRNA and a DDRT clone W19 to Solanum tuberosum 3-hydroxy-3-methylglutaryl coenzyme A reductase mRNA.

• The Journal of the Acoustical Society of Korea
• /
• v.20 no.4E
• /
• pp.3-16
• /
• 2001

An ASCII encoding of Korean has been developed for extended phonetic transcription of the Speech Assessment Methods Phonetic Alphabet (SAMPA). SAMPA is a machine-readable phonetic alphabet used for multilingual computing. It has been developed since 1987 and extended to more than twenty languages. The motivating factor for creating Korean SAMPA (K-SAMPA) is to label Korean speech for a multilingual corpus or to transcribe native language (Ll) interfered pronunciation of a second language learner for bilingual education. Korean SAMPA represents each Korean allophone with a particular SAMPA symbol. Sounds that closely resemble it are represented by the same symbol, regardless of the language they are uttered in. Each of its symbols represents a speech sound that is spectrally and temporally so distinct as to be perceptually different when the components are heard in isolation. Each type of sound has a separate IPA-like designation. Korean SAMPA is superior to other transcription systems with similar objectives. It describes better the cross-linguistic sound quality of Korean than the official Romanization system, proclaimed by the Korean government in July 2000, because it uses an internationally shared phonetic alphabet. It is also phonetically more accurate than the official Romanization in that it dispenses with orthographic adjustments. It is also more convenient for computing than the International Phonetic Alphabet (IPA) because it consists of the symbols on a standard keyboard. This paper demonstrates how the Korean SAMPA can express allophonic details and prosodic features by adopting the transcription conventions of the extended SAMPA (X-SAMPA) and the prosodic SAMPA(SAMPROSA).

• BMB Reports
• /
• v.51 no.6
• /
• pp.290-295
• /
• 2018

Y-box binding protein 1 (YB-1) is a member of the cold-shock domain (CSD) protein superfamily. It participates in a wide variety of cellular events, including transcription, RNA splicing, translation, DNA repair, drug resistance, and stress responses. We investigated putative functions of YB-1 in HIV-1 replication. Functional studies using overexpression or knockdown of YB-1 in conjunction with transfection of proviral DNA showed that YB-1 enhances virus production. We found YB-1 regulates HIV-1 production by stimulating viral transcription using HIV-1 LTR sequence U3RU5 with Luciferase assay. We also identified a specific region from amino acids 1 to 324 of YB-1 as necessary for the participation of the protein in the production of virions.

• International Journal of Oral Biology
• /
• v.44 no.1
• /
• pp.20-26
• /
• 2019

Periodontal diseases have been associated with the development of cardiovascular diseases. Accumulating evidences have indicated that Porphyromonas gingivalis, a major periodontopathic pathogen, plays a critical role in the pathogenesis of atherosclerosis. In the present study, we demonstrated that P. gingivalis lipopolysaccharide (LPS) increases the mRNA and protein expression of matrix metalloproteinase-9 (MMP-9) in rat vascular smooth muscle cells. We showed that the MMP-9 expression induced by P. gingivalis LPS is mediated by the activation of signal transducer and activator of transcription 3 (STAT3) in vascular smooth muscle cells. Furthermore, the inhibition of STAT3 activity reduced P. gingivalis LPS-induced migration of vascular smooth muscle cells. Overall, our findings indicate that P. gingivalis LPS stimulates the migration of vascular smooth muscle cells via STAT3-mediated MMP-9 expression.

• BMB Reports
• /
• v.48 no.6
• /
• pp.319-323
• /
• 2015

Mesenchymal stem cells (MSCs) are multipotent stem cells capable of differentiating into adipocytes, osteoblasts, or chondrocytes. A mutually inhibitory relationship exists between osteogenic and adipogenic lineage commitment and differentiation. Such cell fate decision is regulated by several signaling pathways, including Wnt and bone morphogenetic protein (BMP). Accumulating evidence indicates that microRNAs (miRNAs) act as switches for MSCs to differentiate into either osteogenic or adipogenic lineage. Different miRNAs have been reported to regulate a master transcription factor for osteogenesis, such as Runx2, as well as molecules in the Wnt or BMP signaling pathway, and control the balance between osteoblast and adipocyte differentiation. Here, we discuss recent advancement of the cell fate decision of MSCs by miRNAs and their targets. [BMB Reports 2015; 48(6): 319-323]

• Journal of Microbiology and Biotechnology
• /
• v.19 no.12
• /
• pp.1557-1564
• /
• 2009

Human CDX2 is known as a caudal-related homeodomain transcription factor that is expressed in the intestinal epithelium and is important in differentiation and maintenance of the intestinal epithelial cells. The caudal-related homeobox proteins bind DNA according to a helix-turn-helix structure, thereby increasing the structural stability of DNA. A cancer-tumor suppressor role for Cdx2 has been shown by a decrease in the level of the expression of Cdx2 in colorectal cancer, but the mechanism of transcriptional regulation has not been examined at the molecular level. We developed a large-scale system for expression of the recombinant, novel CDX2, in Escherichia coli. A highly purified and soluble CDX2 protein was obtained in E. coli strain BL21(DE3)RIL and a hexahistidine fusion system using Ni-NTA affinity column, anion exchange, and gel filtration chromatographies. The identity and secondary structure of the purified CDX2 protein were confirmed by MALDI-TOF MS, Western blot, and a circular dichroism analyses. In addition, we studied the DNA-binding activity of recombinant CDX2 by ELISA experiment and isolated human CDX2-binding proteins derived from rat cells by an immobilized GST-fusion method. Three CDX2-binding proteins were found in the gastric tissue, and those proteins were identified to the homeobox protein Hox-D8, LIM homeobox protein 6, and SMC1L1 protein.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.46 no.1
• /
• pp.11-22
• /
• 2020

In this study, we investigated anti-pigmentation effect of a hexapeptide. The peptide significantly reduced melanin contents and inhibited tyrosinase activity in a dose-dependent manner, in which tyrosinase is a key enzyme in melanogenesis. The peptide also significantly reduced the expression levels of tyrosinase (TYR), tyrosinase-related protein 1 (TYRP1) and their upstream transcription factor, microphthalmia-associated transcription factor (MITF). Furthermore, the peptide suppressed the phosphorylation level of cAMP-response element binding protein (CREB), a transcription factor of MITF, and increased the phosphorylation level of extracellular signal-regulated kinase (ERK), a kinase mediates MITF phosphorylation and proteasomal degradation. The peptide significantly inhibited the expression of Rab27A, Melanophilin, and MyosinVa, the components of motor complex involved in intracellular movement of melanosome. These results suggest that Hexapeptide could be used as an effective whitening agent that has inhibitory effect on melanin production and melanosome transport by regulating expression and degradation of MITF in melanocytes.