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981.
982.
In this study, we developed a human prostatic epithelial cell line BPH-1-AR stably expressing AR by lentiviral transduction. Characterization by immunoblot and RT-PCR showed that AR was stably expressed in all representative BPH-1-AR clones. Androgen treatment induced a secretory differentiation phenotype in BPH-1-AR cells but suppressed their cell proliferation. Treatments with AR agonists induced transactivation of a transfected PSA-gene promoter reporter in BPH-1-AR cells, whereas this transactivation was suppressed by an AR antagonist flutamide, indicating that the transduced AR in BPH-1-AR cells was functional. Finally, we utilized BPH-1-AR cells to evaluate the androgenic activities and growth effects of five newly developed non-steroidal compounds. Results showed that these compounds showed androgenic activities and growth-inhibitory effects on BPH-1-AR cells. Our results showed that BPH-1-AR cell line would be a valuable in vitro model for the study of androgen-regulated processes in prostatic epithelial cells and identification of compounds with AR-modulating activities. 相似文献
983.
Han Lu Shengwu You Fujun Zhang Buwei Yu 《Biochemical and biophysical research communications》2009,390(3):872-662
Post-translational modification of proteins by the small ubiquitin-like modifiers (SUMOs) has emerged as an important regulatory mechanism for alteration of protein activity, stability, and cellular localization. It has been reported that SUMOylation plays an important role in some activities of neuronal cells. However, the link between SUMOylation and activity-dependent stimuli of neurons remains to be elucidated. Here we showed that KCl-induced depolarization increased SUMO conjugation in SHSY5Y cell line in a time-dependent manner. The increase of SUMOylation was largely dependent on calcium influx and intracellular calcium signals. Our study demonstrates the link between the activity-dependent stimuli and global SUMOs conjugation, which may play an important role in activity-dependent signals of neurons. 相似文献
984.
Cecilia Herraiz 《FEBS letters》2009,583(19):3269-3274
Melanocortin 1 receptor (MC1R), a Gs protein-coupled receptor expressed in melanocytes, is a major determinant of skin pigmentation, phototype and cancer risk. MC1R activates cAMP and mitogen-activated protein kinase ERK1/ERK2 signalling. When expressed in rat pheochromocytoma cell line cells, the R151C, R160W and D294H MC1R variants associated with melanoma and impaired cAMP signalling mediated ERK activation and ERK-dependent, agonist-induced neurite outgrowth comparable with wild-type. Dose-response curves for ERK activation and cAMP production indicated higher sensitivity of the ERK response. Thus, the melanoma-associated MC1R mutations impact differently on cAMP and ERK signalling, suggesting that cAMP is not responsible for functional coupling of MC1R to the ERK cascade. 相似文献
985.
Cotton (Gossypium spp.) plant growth is an important time-specific agronomic character that supports the development of squares, flowers, boll
retention, and yield. With the use of a mixed linear model approach, we investigated 14 cotton chromosome substitution (CS-B)
lines and their chromosome-specific F2 hybrids for genetic changes in plant growth that was measured during the primary flowering time under two environments. The
changes in additive and dominance variances for plant height and number of mainstem nodes are reported, showing that additive
effects for these two traits were a key genetic component after initial flowering occurred in the field. Time-specific genetic
variance components were also detected where phenotypic values observed at time t were conditioned on the events occurring at time t − 1, demonstrating new genetic variations arising at several time intervals during plant growth. Results also revealed that
plant height and number of nodes shared some common influence due to additive effects during plant development. With the comparative
analyzes, chromosomes associated with the genetic changes in plant growth were detected. Therefore, these results should add
new understanding of the genetics underlying these time-specific traits.
Mention of trademark or proprietary product does not constitute a guarantee or warranty of the product by the United States
Department of Agriculture and does not imply its approval to the exclusion of other products that may also be suitable. 相似文献
986.
987.
A new cell line, designated as NIAS-Boma-529b, was established from the larval fat bodies of Bombyx mandarina (B. mandarina), which is believed to be an ancestor of Bombyx mori (B. mori). This cell line has been cultured for approximately 150 passages during 2 years in an IPL-41 medium supplemented with 10% fetal bovine serum at a constant temperature of 26 °C. The morphology of this line includes adhesive round and spindle-shaped cells. Random-amplified polymorphic DNA analysis (RAPD) using 7 primers and a statistical analysis based on Nei’s genetic distance revealed that this cell line was closely related to B. mori-derived cell lines. An infection study also revealed that this cell line was susceptible to B. mori nucleopolyhedrovirus (BmNPV); however, it had no apparent susceptibility to Autographa californica NPV (AcNPV), which is closely related to BmNPV. Nevertheless, cells infected with AcNPV showed an extensive cytopathic effect (CPE), including a rough cell surface, rounding, nuclear expansion, and cell blebbing. These results suggest that this cell line can be useful to clarify the mechanism of host range determination of BmNPV and AcNPV. 相似文献
988.
Richard H.W. Funk Thomas Monsees Nurdan Özkucur 《Progress in histochemistry and cytochemistry》2009,43(4):177-264
In this review we compile and discuss the published plethora of cell biological effects which are ascribed to electric fields (EF), magnetic fields (MF) and electromagnetic fields (EMF). In recent years, a change in paradigm took place concerning the endogenously produced static EF of cells and tissues. Here, modern molecular biology could link the action of ion transporters and ion channels to the “electric” action of cells and tissues. Also, sensing of these mainly EF could be demonstrated in studies of cell migration and wound healing. The triggers exerted by ion concentrations and concomitant electric field gradients have been traced along signaling cascades till gene expression changes in the nucleus.Far more enigmatic is the way of action of static MF which come in most cases from outside (e.g. earth magnetic field).All systems in an organism from the molecular to the organ level are more or less in motion. Thus, in living tissue we mostly find alternating fields as well as combination of EF and MF normally in the range of extremely low-frequency EMF. Because a bewildering array of model systems and clinical devices exits in the EMF field we concentrate on cell biological findings and look for basic principles in the EF, MF and EMF action.As an outlook for future research topics, this review tries to link areas of EF, MF and EMF research to thermodynamics and quantum physics, approaches that will produce novel insights into cell biology. 相似文献
989.
目的:取肾癌病人标本建立一株新的人肾癌细胞系,初步对该细胞系进行鉴定,为进一步的肾癌基础研究提供实验模型.方法:2008-2009年间共采集20例肾癌新鲜手术标本,于手术后1 h内将每例标本切取四块0.5cm× 0.5 cm× 0.5 cm组织块,分别包埋于2只裸鼠的右后肢皮下及背部皮下,连续传代3次,取移植瘤体外培养,记录细胞株的生长曲线,测定细胞集落形成率,对细胞进行DNA含量测定,进行染色体分析及病理学检查.结果:其中1只裸鼠皮下移植瘤生长,继续传代,肿瘤生长速度明显加快.取移植瘤标本体外培养得到肾癌细胞系XJG-9201.形态结构,分化程度与原发瘤一致,染色体众数为65.细胞群体倍增时间为38.2h,细胞周期分析G1期62.7%,G2期11.2%,S1期25.3%,集落形成率为70%.结论:肾癌细胞系XJG-9201与原发癌保持相同的生物学特性,体外连续传代1年以上传115代.细胞形态不变,生长周期恒定,已成为一个稳定的细胞系. 相似文献
990.
Oryza minuta, a tetraploid wild relative of cultivated rice, is an important source for the genetic improvement. Interspecific hybrids were obtained from the cross of O. sativa L. (IR24) and O. minuta (Acc. No. 101133) with 5.58% crossability, which ranged from 0.11% to 1.62% in the backcross generations. The chromosome numbers of the backcross progenies were 24 to 48. Seven yield-related traits of the parents, hybrid F1, and backcross progenies were evaluated. Simple sequence repeat markers analysis showed that the polymorphism ratio of SSR bands between IR24 and Acc. No. 101133 was 93.2%. The average donor segment number, length, donor genome size, and percentage of donor genome of 92 BC3F1 plants (2n=24) were 24.1, 17.8 cM, 438.4 cM and 26.2%, respectively. They were complex variation and uneven among the chromosomes. These introgression lines could be used to identify the favorable genes of O. minuta and provide a new platform for the genetic improvement of cultivated rice. 相似文献