520 research outputs found
Molecular Characterization and Expression Analysis of Pathogenesis related Protein 6 from Panax ginseng
Panax ginseng Meyer is one of the important medicinal plants in the world, particularly in Asian
countries. Ginseng encounters many stress exposure during its long cultivation period. However, the molecular
mechanism of stress resistance is still poorly understood in spite of its importance. In this study, pathogenesis-
related protein 6 (PR6), also called proteinase inhibitor (PI), was isolated from ginseng embryogenic
callus, named PgPR6. The small size of PR6, containing an open reading frame of 219 bp encoding 72 amino
acids, the typical characteristic of PR6 protein, shares the highest sequence similarity to PR6 of Theobroma
cacao (69% identity). Sequence and structural analysis indicated that PgPR6 belongs to class Kunitz-type PI
family. This is the first report pertaining to the identification of PR6 gene from the P. ginseng genome. The
high-level expression of PgPR6 was observed in root as revealed by quantitative real-time PCR. The temporal
expression analysis demonstrated that PgPR6 expression was highly up-regulated by signaling molecules,
heavy metals, mechanical wounding, chilling, salt, sucrose, and mannitol stress, indicating that PgPR6 may
play an important role in the molecular defense response of ginseng to a various range of environmental
stresses
Overexpression of a cytosolic ascorbate peroxidase from Panax ginseng enhanced salt tolerance in Arabidopsis thaliana
Ascorbate peroxidase (APX) plays an essential role in the antioxidant defense mechanism in the plant, serving in the ascorbateâglutathione cycle for the cellular H2O2 metabolism process. As the perennial plant, Panax ginseng Meyer encounters a lot of unfavorable growth conditions, and among them soil salinity significantly decreases the yield. Two APX genes from Panax ginseng were isolated and designated as PgAPX1 and PgAPX2, which are most similar with previously characterized cytosolic APX of Daucus carota and Spuriopimpinella brachycarpa, as revealed by sequence analysis of their deduced amino acid sequences. PgAPXs transcripts are most abundant in leaf tissue, whereas PgAPX1 expression level was higher compared to PgAPX2. Consistent with higher PgAPX1 expression during salt stress in ginseng, PgAPX1-overexpressing Arabidopsis lines (PgAPX1ox) increased the germination rate and root length compared with wild-type (WT) under 200 mM NaCl stress treatment. Furthermore, higher chlorophyll content, relative water content, total APX activity, proline content, and lower H2O2 accumulation were shown in PgAPX1ox plants compared to WT under 200 mM NaCl stress condition. Transcription analysis showed that PgAPX1oxArabidopsis lines were more salt-tolerant by upregulating the ion homeostasis mechanism
Ectopic overexpression of the aluminum-induced protein gene from Panax ginseng enhances heavy metal tolerance in transgenic Arabidopsis
Aluminum (Al), one of the most abundant metals in agricultural soils, significantly limits crop growth and productivity in acidic soil by inhibiting root elongation. Al ions, especially Al3+, have a toxic effect on both plant and animal cells under low-pH conditions. We first isolated and characterized aluminum-induced protein (AIP) cDNA from a 4-year-old root of Panax ginseng Meyer. This cDNA encodes an open reading frame of 711 bp with a deduced amino acid sequence of 236 residues. The calculated molecular mass of the mature protein is approximately 58.9 kDa with a predicated isoelectric point of 5.13. The Panax ginsengAIP (PgAIP) contains a domain also present in wheat aluminum-induced protein 7 (Wali7) and shares homology with the AIPs of other species, including Codonopis and Arabidopsis. The PgAIP gene was abundantly expressed in the plantâs leaves and was up-regulated by Al exposure. The functional role of PgAIP in Al tolerance was further validated through its overexpression in Arabidopsis. Transgenic Arabidopsis plants overexpressing the PgAIP gene showed enhanced Al tolerance in terms of root growth when compared to wild-type plants, suggesting PgAIP is important in plant defense against Al toxicity. Confocal analysis of CFP-tagging PgAIP in Arabidopsis showed subcellular localization in the plasma membrane. Our results suggest that PgAIP in the plasma membrane plays an important role in the protection of plant cells against heavy metal exposure
Acute hypertensive pulmonary edema after Cesarean section in a patient with an antepartum myocardial infarction -A case report-
We report a case of 29-year-old, morbidly obese, diabetic primigravida who had undergone previously primary percutaneous coronary intervention with stent placement for an inferior wall myocardial infarction at 10 weeks of gestation. She remained asymptomatic with medication during the remainder of her pregnancy, but preoperative echocardiography revealed left ventricular dilation and a restrictive diastolic dysfunction with a preserved ejection fraction (46%). She developed acute pulmonary edema associated with hypertension after an elective Cesarean delivery under continuous epidural anesthesia despite the meticulous restriction of fluid
Cordycepin induces apoptosis of human ovarian cancer cells by inhibiting CCL5-mediated Akt/NF-ÎșB signaling pathway
The chemokine, CCL5, is a key mediator for the recruitment of immune cells into tumors and tissues. Akt/NF-ÎșB signaling is significantly activated by CCL5. However, the role of NF-ÎșB inactivation in apoptosis induced by negative regulation of CCL5 remains unclear. Here, we analyzed the effect of cordycepin on NF-ÎșB activity in SKOV-3 cells and found that cordycepin-mediated inhibition of NF-ÎșB signaling induced apoptosis in SKOV-3 cells via the serial activation of caspases. In addition, immune-blotting analysis showed that CCL5 is highly expressed in SKOV-3 cells. In addition to activating caspases, we show that, cordycepin prevents TNF-α-induced increase in CCL5, Akt, NF-ÎșB, and c-FLIPL activation and that CCL5 siRNA could inhibit Akt/NF-ÎșB signaling. Moreover, cordycepin negatively regulated the TNF-α-mediated IÎșB/NF-ÎșB pathway and c-FLIPL activation to promote JNK phosphorylation, resulting in caspase-3 activation and apoptosis. Also, we show that c-FLIPL is rapidly lost in NF-ÎșB activation-deficient. siRNA mediated c-FLIP inhibition increased JNK. SP600125, a selective JNK inhibitor, downregulated p-JNK expression in cordycepin-treated SKOV-3 cells, leading to suppression of cordycepin-induced apoptosis. Thus, these results indicate that cordycepin inhibits CCL5-mediated Akt/NF-ÎșB signaling, which upregulates caspase-3 activation in SKOV-3 cells, supporting the potential of cordycepin as a therapeutic agent for ovarian cancer
- âŠ