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91.
Genetic mapping of ripening and ethylene-related loci in tomato 总被引:5,自引:0,他引:5
J. Giovannoni H. Yen B. Shelton S. Miller J. Vrebalov P. Kannan D. Tieman R. Hackett D. Grierson H. Klee 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(6-7):1005-1013
The regulation of tomato fruit development and ripening is influenced by a large number of loci as demonstrated by the number
of existing non-allelic fruit development mutations and a multitude of genes showing ripening-related expression patterns.
Furthermore, analysis of transgenic and naturally occurring tomato mutants confirms the pivotal role of the gaseous hormone
ethylene in the regulation of climacteric ripening. Here we report RFLP mapping of 32 independent tomato loci corresponding
to genes known or hypothesized to influence fruit ripening and/or ethylene response. Mapped ethylene-response sequences fall
into the categories of genes involved in either hormone biosynthesis or perception, while additional ripening-related genes
include those involved in cell-wall metabolism and pigment biosynthesis. The placement of ripening and ethylene-response loci
on the tomato RFLP map will facilitate both the identification and exclusion of candidate gene sequences corresponding to
identified single gene and quantitative trait loci contributing to fruit development and ethylene response.
Received: 26 October 1998 / Accepted: 13 November 1998 相似文献
92.
Previous studies have found that individuals from rural areas in Malaysia and in El Salvador prefer heavier women than individuals from urban areas. Several explanations have been proposed to explain these differences in weight preferences but no study has explored familiarity as a possible explanation. We therefore sought to investigate participants’ face preferences while also examining the facial characteristics of the actual participants. Our results showed that participants from rural areas preferred heavier-looking female faces than participants from urban areas. We also found that the female faces from the rural areas were rated as looking heavier than the female faces from the urban areas. Our findings are consistent with the hypothesis that familiarity may be contributing to the differences found in face preferences between rural and urban areas given that people from rural and urban areas are exposed to different faces. 相似文献
93.
Bieberich E Silva J Wang G Krishnamurthy K Condie BG 《The Journal of cell biology》2004,167(4):723-734
The formation of stem cell-derived tumors (teratomas) is observed when engrafting undifferentiated embryonic stem (ES) cells, embryoid body-derived cells (EBCs), or mammalian embryos and is a significant obstacle to stem cell therapy. We show that in tumors formed after engraftment of EBCs into mouse brain, expression of the pluripotency marker Oct-4 colocalized with that of prostate apoptosis response-4 (PAR-4), a protein mediating ceramide-induced apoptosis during neural differentiation of ES cells. We tested the ability of the novel ceramide analogue N-oleoyl serinol (S18) to eliminate mouse and human Oct-4(+)/PAR-4(+) cells and to increase the proportion of nestin(+) neuroprogenitors in EBC-derived cell cultures and grafts. S18-treated EBCs persisted in the hippocampal area and showed neuronal lineage differentiation as indicated by the expression of beta-tubulin III. However, untreated cells formed numerous teratomas that contained derivatives of endoderm, mesoderm, and ectoderm. Our results show for the first time that ceramide-induced apoptosis eliminates residual, pluripotent EBCs, prevents teratoma formation, and enriches the EBCs for cells that undergo neural differentiation after transplantation. 相似文献
94.
G Dou PG Sreekumar C Spee S He SJ Ryan R Kannan DR Hinton 《Free radical biology & medicine》2012,53(5):1111-1122
Endoplasmic reticulum (ER) stress is linked to several pathological conditions including age-related macular degeneration. Excessive ER stress initiates cell death cascades which are mediated, in part, through mitochondrial dysfunction. Here, we identify αB crystallin as an important regulator of ER stress-induced cell death. Retinal pigment epithelial (RPE) cells from αB crystallin (-/-) mice, and human RPE cells transfected with αB crystallin siRNA, are more vulnerable to ER stress induced by tunicamycin. ER stress-mediated cell death is associated with increased levels of reactive oxygen species, depletion of glutathione in mitochondria, decreased superoxide dismutase activity, increased release of cytochrome c, and activation of caspases 3 and 4. The ER stress signaling inhibitors, salubrinal and 4-(2-aminoethyl) benzenesulfonyl fluoride, decrease mitochondrial damage and reduce RPE apoptosis induced by ER stress. Prolonged ER stress decreases levels of αB crystallin, thus exacerbating mitochondrial dysfunction. Overexpression of αB crystallin protects RPE cells from ER stress-induced apoptosis by attenuating increases in Bax, CHOP, mitochondrial permeability transition, and cleaved caspase 3. Thus, these data collectively demonstrate that αB crystallin provides critical protection of mitochondrial function during ER stress-induced RPE apoptosis. 相似文献
95.
Decolourization of Direct Red 80 (DR-80) by the white rot fungus Phanerochaete chrysosporium MTCC 787 was investigated employing sequential design of experiments. Media components for growing the white rot fungus were
first screened using Plackett-Burman design and then optimized using response surface methodology (RSM), which resulted in
enhancement in the efficiency of dye removal by the fungus. For determining the effect of media constituents on the dye removal,
both percent dye decolourization and specific dye removal due to maximum enzyme activity were chosen as the responses from
the experiments, and the media constituents glucose, veratryl alcohol, KH2PO4, CaCl2 and MgSO4 were screened to be the most effective with P values less than 0.05. Central composite design (CCD) followed by RSM in the optimization study revealed the following optimum
combinations of the screened media constituents: glucose, 11.9 g l−1; veratryl alcohol, 12.03 mM; KH2PO4, 23.08 g l−1; CaCl2, 2.4 g l−1; MgSO4, 10.47 g l−1. At the optimum settings of the media constituents, complete dye decolourization (100% removal efficiency) and a maximum
specific dye removal due to lignin peroxidase enzyme of 0.24 mg U−1 by the white rot fungus were observed. 相似文献
96.
Tatsuya Kunisue Jeffrey W. Fisher Babatope Fatuyi Kurunthachalam Kannan 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(21):1725-1730
Perchlorate can competitively inhibit iodide uptake by the thyroid gland (TG) via the sodium/iodide symporter, consequently reducing the production of thyroid hormones (THs). Until recently, the effects of perchlorate on TH homeostasis are being examined through measurement of serum levels of TH, by immunoassay (IA)-based methods. IA methods are fast, but for TH analysis, they are compromised by the lack of adequate specificity. Therefore, selective and sensitive methods for the analysis of THs in TG are needed, for assessment of the effects of perchlorate on TH homeostasis. In this study, we developed a method for the analysis of six THs: l-thyroxine (T4), 3,3′,5-triiodo-l-thyronine (T3), 3,3′,5′-triiodo-l-thyronine (rT3), 3,5-diiodo-l-thyronine (3,5-T2), 3,3′-diiodo-l-thyronine (3,3′-T2), and 3-iodo-l-thyronine (3-T1) in TG, using liquid chromatography (LC)–tandem mass spectrometry (MS/MS). TGs used in this study were from rats that had been placed on either iodide-deficient diet or iodide-sufficient diet, and that had either been provided with perchlorate in drinking water (10 mg/kg/day) or control water. TGs were extracted by pronase digestion and then analyzed by LC–MS/MS. The instrumental calibration range for each TH ranged from 1 to 200 ng/ml and showed a high linearity (r > 0.99). The method quantification limits (LOQs) were determined to be 0.25 ng/mg TG for 3-T1; 0.33 ng/mg TG for 3,3′- and 3,5-T2; and 0.52 ng/mg TG for rT3, T3, and T4. Rats were placed on an iodide-deficient or -sufficient diet for 2.5 months, and for the last 2 weeks of that period were provided either perchlorate (10 mg/kg/day) in drinking water or control water. Iodide deficiency and perchlorate administration both reduced TG stores of rT3, T3, and T4. In iodide-deficient rats, perchlorate exacerbated the reduction in levels of THs in TG. With the advances in analytical methodology, the use of LC–MS/MS for measurement of hormone levels in TG will allow more comprehensive evaluations of the hypothalamic-pituitary–thyroid axis. 相似文献
97.
98.
P. Diana Subramanian Saravanakumar D. Sivaganesh V. Sivakumar Yang Li S. Sebastian Ji-Man Kim Padmanathan Karthick Kannan L. Sangeetha Vijayendran K. K. Praneeth 《Luminescence》2023,38(5):625-636
The present investigation deals with the effect of calcination temperature on the structural and thermoluminescent (TL) properties of Zn2SiO4 materials. For this study, Zn2SiO4 was prepared via a simple hydrothermal route and calcinated at temperatures from 700°C to 1100°C in an air atmosphere. TL data of all Zn2SiO4 samples showed two peaks at around 240°C and 330°C due to the formation of the luminescence centre during X-ray irradiation. More interestingly, the Zn2SiO4 sample calcinated at 900°C exhibited a shift in the TL peak (282°C and 354°C) with an optimal TL intensity attributed to its good crystallinity with a well-defined hexagonal plate-like morphology. X-ray-irradiated Zn2SiO4 samples calcinated at 900°C exhibited a high-temperature TL glow curve peak, suggesting that the present material could be used for high-temperature dosimetry applications. 相似文献
99.
100.
Ragan T Kadiri LR Venkataraju KU Bahlmann K Sutin J Taranda J Arganda-Carreras I Kim Y Seung HS Osten P 《Nature methods》2012,9(3):255-258
Here we describe an automated method, named serial two-photon (STP) tomography, that achieves high-throughput fluorescence imaging of mouse brains by integrating two-photon microscopy and tissue sectioning. STP tomography generates high-resolution datasets that are free of distortions and can be readily warped in three dimensions, for example, for comparing multiple anatomical tracings. This method opens the door to routine systematic studies of neuroanatomy in mouse models of human brain disorders. 相似文献