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The use of Hinoki cypress for the formation of healing forest is gradually increased in South Korea, but the germination rate of these seeds is low, and viability determination by conventional methods is destructive and time-consuming. Therefore, the aim of this study was to investigate the potential of Fourier transform infrared (FT-NIR) spectroscopy in determining the viable seeds of Hinoki cypress nondestructively. FT-NIR reflectance spectra for single seeds were collected in the range of 4000–10,000 cm−1 (1000–2500 nm), and a germination test was carried out to determine viability. To differentiate between viable and nonviable seeds, a multivariate classification with partial least square discriminant analysis (PLS-DA) was developed. The best PLS-DA model assigned the seeds to their respective classes, with 97.7–99.2% and 94.4–95.4% accuracy in the calibration and validation sets, respectively. The PLS-DA Beta coefficient revealed the important wavelength to differentiate viable from nonviable seeds, which was attributed to changes in the chemical composition of the seeds, such as lipids and proteins, which might be responsible for the germination ability of the seeds. Variable importance of projection (VIP) was applied on the spectral data which reduced original variables from 1557 to 27. The developed VIP-PLS-DA model resulted into classification accuracy of 97.7% in calibration and 91.7% in the validation set, with maximum normalization data preprocessing method. In conclusion, the results demonstrate the potential of FT-NIR spectroscopy as a powerful nondestructive method for determination of viable Hinoki cypress seeds, which could be applied in the development of an online sorting technique for seed companies and nurseries.

Kalopanax septemlobus is a deciduous medicinal tree species belonging to the family Araliaceae. It contains a number of triterpenoid saponins primarily constituted of hederagenin aglycones. Here, we presented de novo comparative transcriptome analysis using 454 pyrosequencing technology between embryogenic (EC) and nonembryogenic callus (NEC) of K. septemlobus. A total of 372,229 high-quality reads were generated by combining 168,065 EC reads and 204,164 NEC reads, which were then assembled into 80,280 and 63,128 unigenes, respectively. A comparative analysis of transcription profiles showed that 13,766 genes were differentially expressed between EC and NEC. Moreover, functional enrichment analysis revealed that a number of genes involved in the proteolysis and embryogenesis were highly expressed in EC, whereas oxidative stress-responsible genes were overpresented in NEC. Interestingly, the expression levels of genes involved in saponin biosynthesis, such as squalene epoxidase, cytochrome P450s, and glycosyl transferase, were also higher in NEC than in EC, suggesting that their expression is stress-inducible. In this study, we characterized the K. septemlobus transcriptome profiles involved in somatic embryogenesis (SE), which might enhance knowledge of SE process and provide a useful molecular resource for further study of K. septemlobus.

The rapeseed plant (Brassica napus) is one of the top five oil-producing crops in the world. However, its potential for global cultivation is limited due to its sensitivity to cold. We selected five varieties of rapeseed popular in Korea and analyzed their sensitivity to cold stress. Three — ‘Naehan’, ‘Sandongchae’, and ‘Yudal’ — proved more tolerant than the other two — ‘Youngsan’ and ‘Tammi’. Because rapeseed is in the same family (Brassicacae) as Arabidopsis, one would expect that both share similar genes, with protein coding sequences that show >86% homology. We used a cDNA microarray enriched with Arabidopsis cold stress-related genes to examine the molecular background for differences in sensitivity among rapeseed varieties. Their hierarchical clustering patterns for expression were highly correlated with their cold-sensitive phenotypes. For example, expression patterns were similar between ‘Naehan’ and ‘Sandongchae’ as well as between ‘Yudal’ and our Arabidopsis samples. Using co-expression gene sets developed in this laboratory, we further analyzed expression patterns for three cultivars. Three distinct gene sets were commonly enriched in ‘Naehan’ against ‘Youngsan’ and ‘Tammi’, indicating that they could be the core gene sets that confer a high degree of cold tolerance in ‘Naehan’. Knockout plants with down-regulated expression of GSTF2, TRXh5, LTI30, and LACS4 were highly cold-sensitive whereas overexpression of those four genes led to a reversal of this sensitivity. In fact, overexpression of GSTF2 and LTI30 enhanced tolerance, with plants that over-expressed GSTF2 having extremely high tolerance that enabled them to acclimate almost completely to freezing conditions. By comparison, only about 40% of the wild type demonstrated a similar acclimation. Therefore, the genes described here could be useful in furthering our knowledge about other stress responses in rapeseed, thereby facilitating the production of cold-tolerant plants.

beta-catenin/Tcf and NF-kappaB signaling pathways play an important role in biological functions and crosstalk between these pathways has been reported. We found that the modulation of NF-kappaB activity showed a direct correlation with beta-catein/Tcf pathway in human adipose tissue (hASCs) and bone marrow (hBMSCs)-derived mesenchymal stem cells. Expression of lzts2, which inhibits nuclear translocation of beta-catenin and its transactivation activity, was regulated by NF-kappaB activity. Downregulation of lzts2 by RNA interference increased the nuclear translocation of beta-catenin and NF-kappaB activity in hASCs. NF-kappaB activation by the downregulation of lzts2 was accompanied by the increase of beta-TrCP1 expression and the decrease of IkappaB level. Downregulation of lzts2 increased the proliferation of hASCs and hBMSC, and blocked the NF-kappaB inhibitor-induced inhibitory effect on their proliferation and Tcf promoter activation. These findings provide the first evidence that the reciprocal crosstalk between beta-catenin/Tcf pathway and NF-kappaB signaling in hMSCs is mediated through the regulation of lzts2 expression.

Human mesenchymal stem cells(hMSC), that have been reported to be present in bone marrow, adipose tissues, dermis, muscles and peripheral blood, have the potential to differentiate along different lineages including those forming bone, cartilage, fat, muscle and neuron. Therefore, hMSC are attractive candidates for cell and gene therapy. The optimal conditions for hMSC expansion require medium supplemented with fetal bovine serum(FBS). Some forms of cell therapy will involve multiple doses, raising a concern over immunological reactions caused by medium-derived FBS proteins. Previously, we have shown that hADSC can be cultured in human serum(HS) during their isolation and expansion, and that they maintain their proliferative capacity and ability for multilineage differentiation and promote engraftment of peripheral blood-derived CD34 cells mobilized from bone marrow in NOD/SCID mice. In this study we determined whether hADSC grown in HS maintain surface markers expression similar with cells grown in FBS during culture expansion and compared gene expression profile by Affymetrix microarray. Flow cytometry analysis showed that HLA-DR, CD117, CD29 and CD44 expression in HS-cultured hADSC during culture expansion were similar with that in FBS-cultured cells. However, the gene expression profile in HS-cultured hADSC was significantly different from that in FBS-cultured cells. Therefore, these data indicated that HS-cultured hADSC should be used in vivo animal study of hADSC transplantation for direct extrapolation of preclinical data into clinical application.

Cold acclimated plants show an elevated tolerance against subsequent cold stress. Such adaptation requires alterations in gene expression as well as physiological changes. We were interested in gene expression changes at the transcriptional level during adaptation processes. The patterns of transcriptional changes associated with cold acclimation, deacclimation and reacclimation in Arabidopsis leaves were characterized using the Coldstresschip. Gene expression profiles were further analyzed by 'coexpressed gene sets' using gene set enrichment analysis (GSEA). Genes involved in signal transduction through calcium, and cascades of kinases and transcription factor genes, were distinctively induced in the early response of cold acclimation. On the other hand, genes involved in antioxidation, cell wall biogenesis and sterol synthesis were upregulated in the late response of cold acclimation. After the removal of cold, the expression patterns of most genes rapidly returned to the original states. However, photosynthetic light-harvesting complex genes and lipid metabolism-related genes stayed upregulated in cold deacclimated plants compared to non-treated plants. It is also notable that many well-known cold-inducible genes are slightly induced in reacclimation and their expression remains at relatively low levels in cold reacclimation compared to the expression during the first cold acclimation. The results in this study show the dynamic nature of gene expression occurring during cold acclimation, deacclimation and reacclimation. Our results suggest that there is a memory of cold stress and that the 'memory of cold stress' is possibly due to elevated photosynthetic efficiency, modified lipid metabolism, increased calcium signaling, pre-existing defense protein made during first cold acclimation and/or modified signal transduction from pre-existing defense protein.

Angiogenesis is an essential process in physiological and pathological processes and is well-regulated to maintain the cellular homeostasis by balancing the endothelial cells in proliferation and apoptosis. Angiopoietin-1 (Ang1) regulates angiogenesis as a ligand of Tie 2 receptor tyrosine kinase. However, the regulation pathways are not well-understood. To date, only a few of the signaling molecules involved in the Tie 2 receptor tyrosine kinase-mediated angiogenesis have been identified. In this study, we systematically identified tyrosine-phosphorylated proteins in Ang1-induced signaling cascade in human umbilical vein endothelial cells (HUVECs), employing proteomic analyses combining two-dimensional gel electrophoresis, Western analysis using phosphotyrosine antibody and mass spectrometry (MALDI-TOF MS and nanoLC-ESI-q-TOF tandem MS). We report here the identification, semiquantitative analysis, and kinetic changes of tyrosine-phosphorylated proteins in response to Ang1 in HUVECs and identified 66 proteins among 69 protein spots showing significant changes. Of these, p54nrb was validated as a molecule involved in cell migration. These results suggest that Ang1 induces stabilization of neo-vessel network by regulating the phosphorylations of metabolic and structural proteins.

CD9 belongs to the tetraspanin family and is involved in cell motility, osteoclastogenesis, metastasis, neurite outgrowth, myotube formation, and sperm-egg fusion. CD9 also promotes juxtacrine signaling involved in proliferation and attachment. Varying degrees of CD9 expression have been found in human mesenchymal stem cells. In this study, we determined the functional roles of CD9 in human adipose-derived mesenchymal stem cells (hASCs). The CD9 expression in hASCs was down-regulated during culture expansion. A colony-forming unit assay revealed that the clonal expandability of hASCs was directly correlated with the CD9 expression level of the colony. The CD9(high) cells exhibited an increased ability to proliferate, increased cell adhesiveness, and better in vitro tube formation than the CD9(low) cells. The cellular proliferation and attachment of the CD9(high) cells were inhibited upon treatment with a blocking antibody against CD9 and the transduction of a CD9 miRNA lentivirus. The CD9(high) cells showed higher NF-kappaB promoter activity and higher levels of intercellular adhesion molecule 1 than the CD9(low) cells. Reverse transcription-polymerase chain reaction analysis revealed higher endothelial nitric oxide synthase expression in the CD9(high) cells than in the CD9(low) cells. The engraftment and the proangiogenic action of hASCs in a murine model of hindlimb ischemia were significantly higher in the CD9(high) cells than in the CD9(low) cells. This study indicates that CD9 plays roles in cell proliferation and attachment in vitro as well as in in vivo engraftment and that it can be considered as a useful marker to predict the in vivo efficacy of hASCs.