Root explants excised from carnation plants maintained in vitro formed off-white, friable calluses after three weeks of culture
on Murashige and Skoog (MS) medium supplemented with 1 mg l−1 thidiazuron (TDZ) and 1 mg l−1 α-naphthalaneacetic acid (NAA). These calluses were subsequently transferred to MS basal medium where, after an additional
four weeks of culture, approximately 50% of the calluses formed somatic embryos. However, calluses formed on root explants
that had been cultured on MS medium supplemented with 2,4-dichlorophenoxyacetic acid did not produce somatic embryos upon
transfer to MS basal medium. Somatic embryos developed into plantlets and subsequently were grown to maturity. These results
indicate that root explants have a high competence for somatic embryogenesis in carnation.
J. Seo and S.W. Kim contributed equally to this work. 相似文献
Pyrolysis mass spectrometry (PyMS) is a rapid, simple, high-resolution analytical method based on thermal degradation of complex
material in a vacuum, and has been widely applied to the discrimination of closely related microbial strains. Minimally prepared
samples of embryogenic and non-embryogenic calluses derived from various higher plants (sweet potato, morning glory, Korean
ginseng, Siberian ginseng, and balloon flower) were subjected to PyMS for spectral fingerprinting. A dendrogram based on the
unweighted pair group method, with arithmetic mean of pyrolysis mass spectra, divided the calluses into Siberian ginseng embryogenic
callus and the others, which were subsequently divided into embryogenic and non-embryogenic callus groups, regardless of plant
species from which the calluses were derived. In the non-embryogenic callus group, the dendrogram was in agreement with the
known taxonomy of the plants. These results indicate that PyMS analysis could be applied for discriminating plant calluses
based on embryogenic capacity and taxonomic classification. 相似文献
Mesenchymal stromal cells (MSCs) have proven useful for cell and immune therapy, but the molecular constituents responsible for their functionalities, in particular, those on the plasma membrane, remain largely unknown. Here we employed both gel and nongel based MS to analyze human MSCs' membrane proteome before and after adipogenesis. 2-DE of cells that were pretreated with membrane impermeable fluorescent dyes revealed that both the whole cell proteome and the cell surface subproteome were independent of donors. LC coupled with tandem MS analysis of the plasma membrane-containing fraction allowed us to identify 707 proteins, approximately half of which could be annotated as membrane-related proteins. Of particular interest was a subset of ectodomain-containing membrane-bound proteins that encompass most known surface markers for MSCs, but also contain a multitude of solute carriers and ATPases. Upon adipogenic differentiation, this proteomic profile was amended to include several proteins involved in lipid metabolism and trafficking, at the expense of, most noticeably, ectoenzymes. Our results here provide not only a basis for future studies of MSC-specific molecular mechanisms, but also a molecular inventory for the development of antibody-based cell isolation and identification procedures. 相似文献
Inhalation of particulate matter aggravates respiratory symptoms in patients with chronic airway diseases, but the mechanisms underlying this response remain poorly understood. We used a proteomics approach to examine this phenomenon. Treatment of epithelial cells with BSA-coated titanium dioxide (TiO(2)) particles altered 20 protein spots on the two-dimensional gel, and these were then analyzed by nano-LC-MS/MS. These proteins included defense-related, cell-activating, and cytoskeletal proteins implicated in the response to oxidative stress. The proteins were classified into four groups according to the time course of their expression patterns. For validation, RT-PCR was performed on extracts of in vitro TiO(2)-treated cells, and lung issues from TiO(2)-treated rats were analyzed by immunohistochemical staining and enzyme immunoassay. TiO(2) treatment was found to increase the amount of mRNA for macrophage migration-inhibitory factor (MIF). MIF was expressed primarily in epithelium and was elevated in lung tissues and bronchoalveolar lavage fluids of TiO(2)-treated rats as compared with sham-treated rats. Carbon black and diesel exhaust particles also induced expression of MIF protein in the epithelial cells. 相似文献
Catecholamines, including epinephrine (E), norepinephrine (NE), and dopamine (DA), are associated with the response to stressful conditions. However, the relationships of catecholamines with intelligence and their interactions with stress remain unclear. This study assessed stress, intelligence quotient (IQ), and catecholamine levels in 70 healthy subjects to elucidate associations between catecholamines and stress, and between catecholamines and IQ. Additionally, the associations of catecholamines with stress and IQ were analyzed according to hemispheric dominance using the Brain Preference Indicator (BPI). There were positive correlations between the NE/E ratio and the somatization of stress but negative correlations between the E/NE ratio and the somatization of stress among the total number of subjects. In the right-brain-dominant group, a high E/DA ratio was correlated with low levels of stress, somatization and depression, and high NE/E and DA/E ratios were associated with high levels of somatization. In the left-brain-dominant group, high E levels were correlated with low levels of depression. In the total subjects, there were positive correlations between the NE/E and DA/E ratios and the sum of the vocabulary, arithmetic, picture arrangement, and block design IQ subtests. Thus, these catecholamines were associated with stress and IQ, which suggests that the autonomic functional regulation of catecholamine levels in relation to stress may also affect cognitive functions related to intelligence in the brain. Furthermore, the relationships between catecholamines and stress or IQ differed depending on hemispheric dominance, which suggests that the present results could be used to inform the development of personalized therapies based on hemispheric asymmetry.
Biliary fibrosis is an important pathological indicator of hepatobiliary damage. Cholangiocyte is the key cell type involved in this process. To reveal the pathogenesis of biliary fibrosis, it is essential to understand the normal development as well as the aberrant generation and proliferation of cholangiocytes. Numerous reports suggest that the Wnt signaling pathway is implicated in the physiological and pathological processes of cholangiocyte development and ductular reaction. In this review, we summarize the effects of Wnt pathway in cholangiocyte development from embryonic stem cells, as well as the underlying mechanisms of cholangiocyte responses to adult ductal damage. Wnt signaling pathway is regulated in a step-wise manner during each of the liver differentiation stages from embryonic stem cells to functional mature cholangiocytes. With the modulation of Wnt pathway, cholangiocytes can also be generated from adult liver progenitor cells and mature hepatocytes to repair liver damage. Non-canonical Wnt signaling is triggered in the active ductal cells during biliary fibrosis. Targeted control of the Wnt signaling may hold the great potential to reduce and/or reverse the biliary fibrogenic process. 相似文献
Postmenopausal syndrome refers to symptoms caused by the gradual decrease in female hormones after mid-40 years. As a target organ of estrogen, decrease in estrogen causes various changes in brain function such as a decrease in choline acetyltransferase and brain-derived neurotrophic factor; thus, postmenopausal women experience cognitive decline and more depressive symptoms than age-matched men. Radix Polygalae has been used for memory boosting and as a mood stabilizer and its components have shown neuroprotective, antidepressant, and stress relief properties. In a mouse model of estrogen depletion induced by 4-vinylcyclohexene diepoxide, Radix Polygalae was orally administered for 3 weeks. In these animals, cognitive and depression-related behaviors and molecular changes related to these behaviors were measured in the prefrontal cortex and hippocampus. Radix Polygalae improved working memory and contextual memory and despair-related behaviors in 4-vinylcyclohexene diepoxide-treated mice without increasing serum estradiol levels in this model. In relation to these behaviors, choline acetyltransferase and brain-derived neurotrophic factor in the prefrontal cortex and hippocampus and bcl-2-associated athanogene expression increased in the hippocampus. These results implicate the possible benefit of Radix Polygalae in use as a supplement of estrogen to prevent conditions such as postmenopausal depression and cognitive decline. 相似文献
Tumor necrosis factor (TNF) signaling leads to pleiotropic responses in a wide range of cell types, in part by activating antiapoptotic and proapoptotic pathways. Previous studies have suggested that TNF receptor-associated factor (TRAF) 2 can mediate crucial antiapoptotic signals during TNF stimulation. However, it is unclear how the antiapoptotic signals via TRAF2 in TNF-R1 signaling is regulated. Here we show that TRAF1 is cleaved by caspase-8 into two fragments during apoptosis induced by TNF. Overexpression of the C-terminal cleavage product, TRAF1-c, increased TNF-induced cell death of hybridoma T cells. Importantly, we demonstrate that the cleavage product of TRAF1 coimmunoprecipitates with TRAF2 that is released from the TNF-R1 complex in response to prolonged TNF treatment. These results indicate that caspase-dependent cleavage of TRAF1 generates TRAF1-c fragments that are able to bind TRAF2, and then sequester TRAF2 from the TNF-R1 complex, rendering cells, at least in part, sensitive to TNF. 相似文献
The molecular mechanisms that control the function of periodontal ligament (PDL) fibroblasts remain unclear. We speculated that the character of differentiating PDL fibroblasts is defined by the altered expansion of specific genes not found in neighboring gingival fibroblasts in the periodontium. To expand this set, subtractive hybridization was applied between cultured human PDL and gingival fibroblasts to identify genes differentially expressed in PDL. Consequently five candidate clones, PDLs (periodontal ligament specific) 5, -17, -22, -25, and -31 were identified and characterized by homology search, Northern analysis, and in situ hybridization. Although the mRNAs of these clones were expressed by bone marrow cells and rarely by gingival fibroblasts, the highest expression was detected in the PDL cells, which were uniformly distributed throughout the whole PDL. Amongst the five candidate clones, we focused on PDLs17, because it is a hypothetical protein whose biological function has not been reported yet in the database. Polyclonal antiserum raised against PDLs17 peptide was made, and stained the PDL fibroblasts, osteoblast-like cells and stromal cells in the bone marrow, but not gingival fibroblasts. The results suggest that clones, PDLs5, -17, -22, -25, and -31 may be used as PDL fibroblast-specific markers, and that PDLs17 could act as an important factor in the differentiation process of PDL fibroblasts. 相似文献