Salt cress 유전자의 형질전환을 통한 내염성 식물체 선별

백동원,최원균,강송화,신길옥,박수정,김찬민,박형철,윤대진 한국식물생명공학회 2014 식물생명공학회지 Vol.41 No.2

Salt cress (Thellungiella halophila or Thellungiellaparvula), species closely related to Arabidopsis thaliana,represents an extremophile adapted to harsh saline environments. To isolate salt-tolerance genes from this species, we constructeda cDNA library from roots and leaves of salt cress plantstreated with 200 mM NaCl. This cDNA library was subsequentlyshuttled into the destination binary vector [drivenby the cauliflower mosaic virus (CaMV) 35S promoter]designed for plant transformation and expression via recombination-assisted cloning. In total, 305,400 pools of transgenicBASTA-resistant lines were generated in Arabidopsis usingeither T. halophila or T. parvula cDNA libraries. These wereused for functional screening of genes involved in salttolerance. Among these pools, 168,500 pools were used forprimary screening to date from which 7,157 lines showedapparent salt tolerant-phenotypes in the initial screen. Asecondary screen has now identified 165 salt tolerant transgeniclines using 1,551 (10.6%) lines that emerged in the firstscreen. The prevalent phenotype in these lines includes acceleratedseed germination often accompanied by faster root growthcompared to WT Arabidopsis under salt stress condition. Inaddition, other lines showed non-typical development of stemsand flowers compared to WT Arabidopsis. Based on the closerelationship of the tolerant species to the target species wesuggest this approach as an appropriate method for the largescaleidentification of salt tolerance genes from salt cress.

Long-Term Priming by Three Small Molecules Is a Promising Strategy for Enhancing Late Endothelial Progenitor Cell Bioactivities

김연주,지승택,김다연,정석윤,강송화,박지혜,장웅비,윤지수,하종성,이동형,권상모 한국분자세포생물학회 2018 Molecules and cells Vol.41 No.6

Endothelial progenitor cells (EPCs) and outgrowth endothelial cells (OECs) play a pivotal role in vascular regeneration in ischemic tissues; however, their therapeutic application in clinical settings is limited due to the low quality and quantity of patient-derived circulating EPCs. To solve this problem, we evaluated whether three priming small molecules (tauroursodeoxycholic acid, fucoidan, and oleuropein) could enhance the angiogenic potential of EPCs. Such enhancement would promote the cellular bioactivities and help to develop functionally improved EPC therapeutics for ischemic diseases by accelerating the priming effect of the defined physiologi-cal molecules. We found that preconditioning of each of the three small molecules significantly induced the differentiation potential of CD34+ stem cells into EPC lineage cells. Notably, long-term priming of OECs with the three chemical cocktail (OEC-3C) increased the pro-liferation potential of EPCs via ERK activation. The migration, invasion, and tube-forming capacities were also significantly enhanced in OEC-3Cs compared with unprimed OECs. Further, the cell survival ratio was dra-matically increased in OEC-3Cs against H2O2-induced oxidative stress via the augmented expression of Bcl-2, a pro-survival protein. In conclusion, we identified three small molecules for enhancing the bioactivities of ex vivo-expanded OECs for vascular repair. Long-term 3C priming might be a promising methodology for EPC-based therapy against ischemic diseases.

A Role for Arabidopsis miR399f in Salt, Drought, and ABA Signaling

Dae-Jin Yun,Dongwon Baek,전현진,강송화,신길옥,박수정,Hyewon Hong,Chanmin Kim,Doh-Hoon Kim,Sang Yeol Lee,Min-Chul Kim 한국분자세포생물학회 2016 Molecules and cells Vol.39 No.2

MiR399f plays a crucial role in maintaining phosphate homeostasis in Arabidopsis thaliana. Under phosphate starvation conditions, AtMYB2, which plays a role in plant salt and drought stress responses, directly regulates the expression of miR399f. In this study, we found that miR399f also participates in plant responses to abscisic acid (ABA), and to abiotic stresses including salt and drought. Salt and ABA treatment induced the expression of miR399f, as confirmed by histochemical analysis of promoter-GUS fusions. Transgenic Arabidopsis plants overexpressing miR399f (miR399f-OE) exhibited enhanced tolerance to salt stress and exogenous ABA, but hypersensitivity to drought. Our in silico analysis identified ABF3 and CSP41b as putative target genes of miR399f, and expression analysis revealed that mRNA levels of ABF3 and CSP41b decreased remarkably in miR399f-OE plants under salt stress and in response to treatment with ABA. Moreover, we showed that activation of stress-responsive gene expression in response to salt stress and ABA treatment was impaired in miR399f-OE plants. Thus, these results suggested that in addition to phosphate starvation signaling, miR399f might also modulates plant responses to salt, ABA, and drought, by regulating the expression of newly discovered target genes such as ABF3 and CSP41b.

Regular Exercise Training Increases the Number of Endothelial Progenitor Cells and Decreases Homocysteine Levels in Healthy Peripheral Blood

최정규,문기명,정석윤,김지용,최성현,김다연,강송화,주종우,권상모 대한약리학회 2014 The Korean Journal of Physiology & Pharmacology Vol.18 No.2

Endothelial progenitor cells (EPCs) are known to play an important role in the repair of damagedblood vessels. We used an endothelial progenitor cell colony-forming assay (EPC-CFA) to determinewhether EPC numbers could be increased in healthy individuals through regular exercise training. The number of functional EPCs obtained from human peripheral blood-derived AC133 stem cells wasmeasured after a 28-day regular exercise training program. The number of total endothelial progenitorcell colony-forming units (EPC-CFU) was significantly increased compared to that in the control group(p=0.02, n=5). In addition, we observed a significant decrease in homocysteine levels followed by anincrease in the number of EPC-CFUs (p=0.04, n=5), indicating that the 28-day regular exercise trainingcould increase the number of EPC colonies and decrease homocysteine levels. Moreover, an inversecorrelation was observed between small-endothelial progenitor cell colony-forming units (small-EPCCFUs)and plasma homocysteine levels in healthy men (r=- 0.8125, p=0.047). We found that regularexercise training could increase the number of EPC-CFUs and decrease homocysteine levels, thusdecreasing the cardiovascular disease risk in men.

Pharmacological inhibition of mTOR attenuates replicative cell senescence and improves cellular function via regulating the STAT3-PIM1 axis in human cardiac progenitor cells

Ji Hye Park,Na Kyoung Lee,Hye Ji Lim,Seung Taek Ji,김연주,Woong Bi Jang,Da Yeon Kim,강송화,Jisoo Yun,Jongseong Ha,Hyungtae Kim,Dongjun Lee,백상홍,권상모 생화학분자생물학회 2020 Experimental and molecular medicine Vol.52 No.-

The mammalian target of rapamycin (mTOR) signaling pathway efficiently regulates the energy state of cells and maintains tissue homeostasis. Dysregulation of the mTOR pathway has been implicated in several human diseases. Rapamycin is a specific inhibitor of mTOR and pharmacological inhibition of mTOR with rapamycin promote cardiac cell generation from the differentiation of mouse and human embryonic stem cells. These studies strongly implicate a role of sustained mTOR activity in the differentiating functions of embryonic stem cells; however, they do not directly address the required effect for sustained mTOR activity in human cardiac progenitor cells. In the present study, we evaluated the effect of mTOR inhibition by rapamycin on the cellular function of human cardiac progenitor cells and discovered that treatment with rapamycin markedly attenuated replicative cell senescence in human cardiac progenitor cells (hCPCs) and promoted their cellular functions. Furthermore, rapamycin not only inhibited mTOR signaling but also influenced signaling pathways, including STAT3 and PIM1, in hCPCs. Therefore, these data reveal a crucial function for rapamycin in senescent hCPCs and provide clinical strategies based on chronic mTOR activity.