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41.
Incorporation of one micromolar IAA in the assay system increased the rate of 14C methionine uptake by tomato cells in suspension and effectively differentiated the rates of uptake such that cells treated with pathogenic and non-pathogenic Fusarium extracts could be easily distinguished in a rapid 3 h assay. 相似文献
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Christian P Craddock Nicolette Adams Fiona M Bryant Smita Kurup Peter J Eastmond 《Plant signaling & behavior》2015,10(10)
Coordination of membrane lipid biosynthesis is important for cell function during plant growth and development. Here we summarize our recent work on PHOSPHATIDIC ACID PHOSPHOHYDROLASE (PAH) which suggests that this enzyme is a key regulator of phosphaticylcholine (PC) biosynthesis in Arabidopsis thaliana. Disruption of PAH activity elevates phosphatidic acid (PA) levels and stimulates PC biosynthesis and biogenesis of the endoplasmic reticulum (ER). Furthermore, the activity of PHOSPHOCHOLINE CYTIDYLYLTRANSFERASE (CCT), which is the key enzyme controlling the rate of PC biosynthesis, is directly stimulated by PA and expression of a constitutively active version of CCT replicates the effects of PAH disruption. Hence PAH activity can control the abundance of PA, which in turn can modulate CCT activity to govern the rate of PC biosynthesis. Crucially it is not yet clear how PAH activity is regulated in Arabidopsis but there is evidence that PAH1 and PAH2 are both phosphorylated and further work will be required to investigate whether this is functionally significant. 相似文献
46.
The anticancer drug taxol brings about its biological effects by altering the stability of microtubules. We have examined the effects of taxol on early morphogenesis in chick embryos culturedin vitro. Taxol induced various abnormalities in the developing nervous system, heart and somites as well as general retardation of development. SEM studies revealed that taxol treatment leads to dramatic alterations in the embryonic cell surfaces. Time-course experiments demonstrated that the action of taxol is very rapid and becomes evident within a few minutes at the ultrastructural level. Taxol thus throws embryonic cell adhesion and motility out of balance. This appears to be the major cause of abnormal morphogenesis in taxol-treated embryos. 相似文献
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Harry J. Wichers Marien P. Harkes Randy R. J. Arroo 《Plant Cell, Tissue and Organ Culture》1990,23(2):93-100
The 5-methoxypodophyllotoxin contents of plants, cell cultures and regenerated plants of Linum flavum are compared. It is demonstrated that cell cultures are able to produce amounts of 5-methoxypodophyllotoxin that are comparable to the concentration in fully differentiated plants. The production of 5-methoxy-podophyllotoxin depends on the hormonal balance of the growth medium. The use of 2,4-dichlorophenoxyacetic acid as the growth regulator is favourable for 5-methoxypodophyllotoxin production when compared to naphthylacetic acid. The 5-methoxypodophyllotoxin accumulation appears to be positively related to the internal cell volume. 相似文献
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We have developed an experimental system in which the irradiation with a red light pulse induces stomatal disorientation in
the hypocotyl epidermis ofCucumis sativus L. In this system, the orientation of the division plane in guard mother cells was not defined correctly. Preprophase bands
formed in these cells but their orientation was abnormal. 相似文献
49.
Behnaz Valipour Kobra Velaei Ali Abedelahi Mohammad Karimipour Masoud Darabi Hojjatollah Nozad Charoudeh 《Journal of cellular physiology》2019,234(11):19352-19365
Natural killer (NK) cells have significant capability in tumor immune-surveillance. The ability of lyse transformed cells immediately in an antigen-independent manner make them an attractive candidate for cancer cell therapy. Despite employment of NK cells in cancer immunotherapy, clinical trials are faced with serious limitations such as trouble with the penetration of NK cells in tumor sites, limited in vivo persistence, and tumor microenvironment interference. Taken together, the NK-cell cancer therapy is still infant scenario that has a long way to be translated in clinic. Current article first reviews characteristic features of NK lymphocytes. Then, it discusses about important disruptive barriers and motivator in the developmental stages of NK cells like as tumor microenvironment. Finally, some revolutionary approaches are highlighted utilizing of NK cells in cancer therapy. 相似文献
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