• 한국균학회소식:학술대회논문집
• /
• 2014.05a
• /
• pp.39-39
• /
• 2014

In a homothallic filamentous fungus Aspergillus nidulans, sexual and asexual developments are largely affected by the genetic and environmental factors. To regulate the complex subsets of genes involved in the developmental processes accurately, tight regulations of transcription factors are required. The forkhead type transcription factors are the class of regulators that function in a broad spectrum of cellular and developmental processes in many species from yeast to human. Here, we identified the fkhA and fkhB genes that encode a conserved forkhead transcription factors. The fkhA deletion resulted in the complete loss of fruiting body formation under all conditions favoring sexual development, suggesting that the fkhA gene is required for sexual development in A. nidulans. Overexpression of fkhA resulted in enhanced formation of fruiting bodies under induction condition not only in the normal condition but also in the condition of presence of 0.6 M KCl, which strongly inhibits sexual development. To know the function of the fkhB gene, we also generated fkhB knock-out strain in A. nidulans. Deletion of fkhB resulted in abnormal conidiophore formation under standard conditions and delayed sexual development process, suggesting that the fkhB gene plays an important role in conidiophore morphogenesis Taken together, these results suggest that the fkhA gene is necessary and sufficient for regulating sexual development and the fkhB gene is a transcription factor related in asexual developmental process in A. nidulans.

• Molecules and Cells
• /
• v.42 no.3
• /
• pp.200-209
• /
• 2019

Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) have been used as promising tools for regenerative medicine, disease modeling, and drug screening. Traditional and common strategies for pluripotent stem cell (PSC) differentiation toward disease-relevant cell types depend on sequential treatment of signaling molecules identified based on knowledge of developmental biology. However, these strategies suffer from low purity, inefficiency, and time-consuming culture conditions. A growing body of recent research has shown efficient cell fate reprogramming by forced expression of single or multiple transcription factors. Here, we review transcription factor-directed differentiation methods of PSCs toward neural, muscle, liver, and pancreatic endocrine cells. Potential applications and limitations are also discussed in order to establish future directions of this technique for therapeutic purposes.

• Journal of Plant Biotechnology
• /
• v.44 no.1
• /
• pp.1-11
• /
• 2017

Evolutionary studies conducted on NAC (NAM, ATAF1&2, and CUC2) genes for all major groups of land plants, indicate the presence of the NAC subfamilies, even in the early land plants. The varied roles played by NAC proteins in plant growth and development range from the formation of shoot apical meristem, floral organ development, reproduction, lateral shoot development, and defense responses to biotic and abiotic stresses. Considering the value and importance of solanaceous crops, the study of NAC proteins in these plants needs to be intensified. This will help to identify and functionally characterize their promoters, which will subsequently aid in engineering plants with improved performance under stressful conditions. In this review, the functionally characterized NAC transcription factors specific to tomato, potato, tobacco, chili pepper and eggplant (aubergine) are summarized, clearly indicating their biological functions in the defense mechanism of the plants, against biotic and abiotic stresses.

• Proceedings of the Korean Society of Plant Pathology Conference
• /
• 2003.10a
• /
• pp.79.1-79
• /
• 2003

Two pathogen-induced hot pepper transcription factors (CaNACl and CapIfl) were introduced into‘MicroTom’tomato by Agrobacterium tumefaciens-mediated transformation. We used to nptII containing kanamycin resistance gene as a selection marker. Both transformed and non-transformed plants were transferred to pot after rooting test in vitro. To approximate the levels of caNACl transcript in leaves of wild-type and transgenic plants, RNA blots were hybridized with double-stranded full-length CaNACl probe at moderate stringency, Although the relative signal strength for hybridization fluctuated among the samples on different blots, transgenic plant lines N-1, N-2 and N-3 consistently displayed increased levels of CaNACl transcript relative to other transgenic lines and wild-type plants. Of all the transgenic lines examined, line N-7 had the least amount of CaNACl transcript. Role of these transcription factors in pathogen defense will be examined by overexpression in tomato.

• Clinical and Experimental Reproductive Medicine
• /
• v.39 no.4
• /
• pp.127-131
• /
• 2012

Primordial follicles are formed prenatally in mammalian ovaries, and at birth they are fated to be activated to primary follicles, to be dormant, or to die. During the early stage of folliclulogenesis, the oocyte undergoes dynamic alterations in expression of numerous genes, which are regulated by transcription factors. Several germ-cell specific transcriptional regulators are critical for formation and maintenance of follicles. These transcriptional regulators include: Figla, Lhx8, Nobox, Sohlh1, and Sohlh2. A subset of these transcriptional regulators is mutated in women with ovarian insufficiency and infertility. Establishment of this oocyte pool is essential for fertility. This review focuses on these transcriptional regulators of female primordial follicles.

• Molecules and Cells
• /
• v.40 no.10
• /
• pp.697-705
• /
• 2017

The maintenance of inorganic phosphate (Pi) homeostasis is essential for plant growth and yield. Plants have evolved strategies to cope with Pi starvation at the transcriptional, post-transcriptional, and post-translational levels, which maximizes its availability. Many transcription factors, miRNAs, and transporters participate in the Pi starvation signaling pathway where their activities are modulated by sugar and phytohormone signaling. Environmental stresses significantly affect the uptake and utilization of nutrients by plants, but their effects on the Pi starvation response remain unclear. Recently, we reported that Pi starvation signaling is affected by abiotic stresses such as salt, abscisic acid, and drought. In this review, we identified transcription factors, such as MYB, WRKY, and zinc finger transcription factors with functions in Pi starvation and other environmental stress signaling. In silico analysis of the promoter regions of Pi starvation-responsive genes, including phosphate transporters, microRNAs, and phosphate starvation-induced genes, suggest that their expression may be regulated by other environmental stresses, such as hormones, drought, cold, heat, and pathogens as well as by Pi starvation. Thus, we suggest the possibility of cross-talk between Pi starvation signaling and other environmental stress signaling pathways.

• The Journal of Korean Medicine
• /
• v.29 no.5
• /
• pp.111-117
• /
• 2008

Objectives and methods : Previous mechanistic studies suggest the cyclooxygenase-2 (COX-2) inhibitors represent the good candidates against tumor progression. MeOH extract of the stem barks of Euonymus alatus induced the strong inhibition of COX-2. A phenolic compound responsible for the anti- COX-2 known to involve in tumor adhesion and invasion has been studied through the methanol extracts. The compound, rosmarinic acid (ROS-A) was an ester of caffeic acid and 3,4-dihydroxyphenyllactic acid. ROS-A showed a strong inhibitory effect of COX-2 activity in a concentration-dependent manner. Then we have measured the IL-1${\beta}$, IL-6 and TNF-${\alpha}$ production related the immune regulation, induction of inflammatory related genes. Results and Conclusions :Hep3B cells produce proinflammatory cytokines of IL-1${\beta}$, IL-6 and TNF-${\alpha}$ while ROS A inhibited the cytokines production. Since IL-1${\beta}$, IL-6 and TNF-${\alpha}$ need the transcription factors such as nuclear factor- ${\kappa}$B (NF-${\kappa}$B) and activated protein-1 (AP-1), we measured the transcription factors. ROS-A inhibited the activation of p65, p50, c-Rel subunits of NF-${\kappa}$B and AP-1 transcription factors. These findings indicate that ROS A from the stem bark of E. alatus inhibits proliferation in metastatic cancer cells. It was suggested that stem barks of E. alatus could be suitable for anti-cancer drugs.

• YAKHAK HOEJI
• /
• v.56 no.5
• /
• pp.326-332
• /
• 2012

Mast cells play pivotal pathologic roles in allergic disease involving T helper 2 (Th2) cytokine such as interleukin (IL)-4 and IL-13. Fisetin has been known as an anti-allergic agent having inhibitory effects on the IL-4 and IL-13 gene expressions in inflammatory immune cells. However, its molecular mechanisms for suppressive effects of fisetin on IL-4 and IL-13 in activated mast cells have been incompletely elucidated. In this study we found that fisetin significantly inhibited the phorbol 12-myristate 13-acetate (PMA) and ionomycin (PI)-induced production of IL-4 and IL-13 in mast cells. The levels of mRNA were dramatically decreased by fisetin, indicating the suppression might be regulated at the transcriptional levels. Western blot analysis of the nuclear expression of various transcription factors involved in the promoter activation indicated that suppression of c-Fos was prominent together with significant down-regulation of nuclear factor of activated T-cell (NF-AT) and NF-${\kappa}B$, but not c-Jun. Furthermore, the nuclear expression of GATA binding protein 2 (GATA-2) transcription factor was significantly down-regulated by fisetin. Taken together, our study indicated fisetin has suppressive effects on IL-4 and IL-13 gene expression through the regulation of selective transcription factors.

• Molecules and Cells
• /
• v.39 no.7
• /
• pp.524-529
• /
• 2016

Controlling the production of diverse cell/tissue types is essential for the development of multicellular organisms such as animals and plants. The Arabidopsis thaliana root, which contains distinct cells/tissues along longitudinal and radial axes, has served as an elegant model to investigate how genetic programs and environmental signals interact to produce different cell/tissue types. In the root, a series of asymmetric cell divisions (ACDs) give rise to three ground tissue layers at maturity (endodermis, middle cortex, and cortex). Because the middle cortex is formed by a periclinal (parallel to the axis) ACD of the endodermis around 7 to 14 days post-germination, middle cortex formation is used as a parameter to assess maturation of the root ground tissue. Molecular, genetic, and physiological studies have revealed that the control of the timing and extent of middle cortex formation during root maturation relies on the interaction of plant hormones and transcription factors. In particular, abscisic acid and gibberellin act synergistically to regulate the timing and extent of middle cortex formation, unlike their typical antagonism. The SHORT-ROOT, SCARECROW, SCARECROW-LIKE 3, and DELLA transcription factors, all of which belong to the plant-specific GRAS family, play key roles in the regulation of middle cortex formation. Recently, two additional transcription factors, SEUSS and GA- AND ABA-RESPONSIVE ZINC FINGER, have also been characterized during ground tissue maturation. In this review, we provide a detailed account of the regulatory networks that control the timing and extent of middle cortex formation during post-embryonic root development.

• The Journal of Natural Sciences
• /
• v.18 no.1
• /
• pp.47-53
• /
• 2007

In order to find novel sRNA in Bacillus subtilis which would be used to adapt to several conditions, we searched the whole genome of Bacillus subtilis using the following procedure. At first, the locations of recognition sequence of transcription factors such as PerR, OhrR, Fur and Zur were searched in the intergenic region of Bacillus subtilis genome and the locations of rho independent transcription terminator sites were also determined. Based on the information of these locations, the sRNA candidates were chosen by close locations (less than 300 bp) between the recognition site of transcription factors and rho independent transcription terminator site. Than transcription promoter sites were searched in the region of previously identified sRNA candidates and 5 PerR, 1 OhrR, 1 Fur and 1 Zur regulated good sRNA candidates were found.