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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Over-expression of the potassium-chloride co-transporter KCC2 in developing zebrafish

Reynolds, Annie, 1978- January 2006 (has links)
No description available.
142

Cellular retinoic acid binding protein (CRABP) mRNA expression in splotch mutant mouse embryos

Roundell, Jennifer. January 1996 (has links)
No description available.
143

Expression, regulation and function of the stem-loop binding protein during mammalian oogenesis

Allard, Patrick January 2005 (has links)
No description available.
144

Identification of biomarkers and copper binding proteins in tilapia and zebrafish by proteomics approaches. / CUHK electronic theses & dissertations collection

January 2010 (has links)
Firstly, a cell line derived from the liver of tilapia, Hepa-T1, was used as a model and exposed to two sub-lethal concentrations of waterborne copper for 96 h. The proteins expressed in Hepa T1 were investigated by differential protein profiling using two-dimensional gel electrophoresis (2-DE). It was found that Cu2+ (120 microM and 300 microM) caused differential expression of 93 different proteins, 18 of which were further verified by real-time quantitative polymerase chain reaction (PCR) analysis. Following analysis with ingenuity pathway software, several proteins were found to be involved in lipid metabolism, tissue connective development and cell cycle control, thus indicating that copper toxicity affects these cellular functions. / Fourthly, to further reveal the mechanism of copper tolerance and sensitivity in tilapia and zebrafish, two important copper transporters (ATP7A & B) and metallothionein (MT) were chosen for studying. Until now, a full length of ATP7A and partial length of ATP7B were obtained in tilapia. Then a real time quantitative PCR was conducted to study the different regulations of these three genes in tilapia and zebrafish. It was found that Cu2+ could induce more MT and ATP7A & B in tilapia than zebrafish both in vivo and in vitro. These results help us to understand that the copper tolerance of tilapia is possibly due to higher expression level of both copper transporters and MT. / Last but not least, I also compared the toxicity and biomarker gene expression in zebrafish exposed to Cu2O nanoparticle (NP) and CuCl2, respectively. It was found that the toxicity of CuCl2 is much higher than that of Cu2O NP. Then seven genes, including MT, ATP7A & B, copper transporter 1 (Ctr1), metal regulatory transcription factor 1 (MTF1), glutathione sulfur transferase (GST), Cu/Zn superoxide dismutase (Cu/Zn SOD), were chosen for studying. It was found that both Cu2O NP and CuCl 2 up-regulated the mRNA levels of MT, Cu/Zn SOD, and Ctr1, ATP7A & 7B, but down-regulated the mRNA levels of GST. Interestingly, the inductions of MT, Ctr1, ATP7A & B in the Cu2O NP exposure groups were much higher than that of CuCl2 exposure groups in vivo . Furthermore, as determined by using Ctr1, ATP7A and ATP7B gene expression, the no observable effect levels (NOELs) of CuCl2 and nano-Cu2O were 11 ppb and 50 ppb, whereas the lowest observable effect levels (LOELs) of CuCl2 and nano-Cu2O were 43 ppb and 125 ppb. (Abstract shortened by UMI.) / Secondly, the high copper contents in the liver of the tilapia make this fish a suitable model for the study of copper binding proteins. Liver was dissected from tilapia injected with Cu2+ and cytosolic fractions were separated by using Superdex 75 column chromatography followed with atomic absorption spectrometry. Fractions containing copper-binding proteins were found in two major peaks, analyzed using differential proteomic approaches, and loaded on a Cu chelating ion-immobilized affinity column (Cu-IMAC). Of the 113 differentially expressed proteins in these two peaks, some well-characterized copper binding proteins were found, including copper transporter ATP7A, cytochrome c oxidase, metallothionein, collagen, catalase, and vitellogenin. These proteins are mainly involved in endocrine disruption, mitochondria dysfunction, ion competition, lipid metabolism, copper transfer, and cytoskeleton disruption. In addition, a more concrete image about copper transportation pathway was hypothesized according to the function of the novel copper binding proteins identified. / The aims of this study are to identify some novel copper binding proteins and proteins related to Cu2+ toxicity or detoxification mechanisms in the tilapia (Oreochromis niloticus) and the zebrafish (Danio rerio) using a proteomic approach, and to reveal the mechanism of copper tolerance and copper sensitivity by comparing the different biochemical responses to copper exposures between the two model species. / Thirdly, zebrafish liver cell line (ZFL) was also used as a model to study the mechanism of copper toxicity. After processing similar experimental procedures of previous Hepa T1 experiment, 72 different proteins were identified to be regulated by Cu2+ (100 microM and 200 microM). More than 50 % of these proteins were also found differentially expressed in the tilapia. The results suggested that the toxicity mechanism between zebrafish and tilapia was generally conserved. Although, in ZFL, the regulation of several proteins, related to ROS effect, mitochondrion copper transportation, and stress response, was quite different from that in tilapia. / Chen, Dongshi. / Adviser: Chun Ung Ming. / Source: Dissertation Abstracts International, Volume: 73-02, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 173-190). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
145

Functional analysis of arabidopsis and rice vacuolar sorting receptor (VSR) proteins. / CUHK electronic theses & dissertations collection

January 2010 (has links)
Vacuolar sorting receptors (VSRs) are type I integral membrane family proteins that mediate protein transport from late Golgi or trans-Golgi network (TGN) to vacuole via prevacuolar compartment (PVC) in plant cells. The N-terminus of a VSR is believed to be important for cargo binding while its transmembrane domain (TMD) and cytoplasmic tail (CT) are essential for its correct subcellular localization. In this study, I first developed and tested an expression system using transgenic tobacco BY-2 cells to produce truncated VSR proteins (VSRNT) lacking the TMD/CT into the cultured media. The secreted VSRs bind specifically to the vacuolar sorting determinants (VSDs) of known vacuolar proteins and such binding is calcium dependent in vitro. Thus, VSR cargo proteins are likely secreted into the cultured media along with the truncated VSRs, which enable the identification of various VSR cargo proteins from the cultured media of transgenic cells. I then identified these putative VSR cargo proteins through liquid-chromatography with tandem mass spectrometry (LC-MS/MS) and Fourier transform mass spectrometry (FT-MS) using transgenic Arabidopsis cell suspension cultures PSB-D expressing these truncated VSRs. Among the 17 unique proteins found in the cultured media of transgenic Arabidopsis PSB-D cell line expressing VSRNT, an Arabidopsis glycosyl hydrolase family 3 protein At5g10560 (GH3) was chosen for further study on VSR-cargo protein interaction. GFP-tagged GH3 fusion protein was found to co-localize with VSR-RFP marker protein in PVC, whereas GH3 was also shown to interact with a VSR protein BP-80. Loss-of-function analysis demonstrated that the GH3 contained a vacuolar sorting determinant (VSD) for PVC targeting. / Suen, Pui Kit. / Source: Dissertation Abstracts International, Volume: 73-02, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 77-84). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
146

Molecular and functional characterization of a novel G-patch containing protein-IER3IP1. / CUHK electronic theses & dissertations collection

January 2003 (has links)
Yiu Wai Han. / "June 2003." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (p. 146-156) / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
147

Therapeutic RNAi targeting CKIP-1 for promoting bone formation in postmenopausal osteoporosis: a translational study of CKIP-1.

January 2012 (has links)
成人骨量的更新与维持通过骨重塑来实现。骨重塑包括骨吸收与骨形成两个偶联的过程,其中成骨细胞介导骨形成,破骨细胞介导骨吸收,当偶联的骨吸收超过骨吸收就会导致骨量丢失,进而导致发生骨质疏松症的发生。目前,临床治疗骨质疏松的药物如阿仑膦酸盐、雌激素受体调节剂、活性维生素D、雌激素替代治疗、降钙素、骨化三醇等都是基于针对破骨细胞的调控来抑制骨吸收,但是对于已经丢失的骨量无法恢复。唯一被美国FDA批准用来通过刺激新骨形成来恢复丢失的骨量的治疗药物就是甲状旁腺激素。然而,这种药物在刺激新骨形成的同时也刺激了骨吸收,即:在使用18个月后有明显促进骨吸收的副作用。 / 酪蛋白激酶相互作用蛋白-1(CKIP-1)基因是一个新发现的骨形成的负调控基因,CKIP-1基因敲除小鼠在骨发育和正常骨代谢过程中均未发现激活骨吸收。CKIP-1敲除导致小鼠胫骨近端骨量与胫骨皮质骨形成速率显著高于野生型,且这一差异随着小鼠的增龄而显著,而骨外器官没有发现异常表型,提示CKIP-1是潜在相对安全的治疗骨质疏松的靶向基因。特别是我们最近研发的一种天门冬氨酸-丝氨酸-丝氨酸重复三肽修饰的脂质体递送((Asp-Ser-Ser)₆-liposome)系统能够实现靶向骨形成表面的小干扰核酸的递送,并明显减少了小干扰核酸在非骨组织的分布。因此,提出本课题的研究假设:特异性静默骨内CKIP-1可以促进骨形成而不刺激骨吸收,从而为骨质疏松的临床治疗提供安全有效的治疗手段。 / 为了确定CKIP-1基因表达在老年绝经后妇女骨骼中与骨形成内在联系,首先,我们通过对发生骨折的老年绝经后妇女的骨痂标本中CKIP-1 mRNA和蛋白表达的测定,发现CKIP-1基因mRNA和蛋白表达水平与骨形成能力负相关。并且,这种相关性在骨质疏松动物模型中进一步得到证实。其次,针对我们研究假设,从一组针对大鼠、小鼠、猴和人类的成骨样细胞的CKIP-1 mRNA的跨种属siRNA序列中筛选出体外静默效率最高CKIP-1小干扰核酸序列si-3。接着,体内外实验证实si-3序列在健康动物体内的静默效率和促进成骨的功能。同时,确定尾静脉注射(Asp-Ser-Ser)₆-liposome 包裹的CKIP-1小干扰核酸在 大鼠和小鼠为的最佳剂量分别为3.75mg/kg和7.5mg/kg以及注射周期为每两周一次。最后,为了检验CKIP-1 小干扰核酸是否可通过促进骨形成从而逆转绝经后骨质疏松症中的骨丢失,我们分别以绝经后骨质疏松大鼠和小鼠为实验动物模型,通过测定骨形态计量学参数、骨量和骨结构等来评价骨靶向递送系统((Asp-Ser-Ser)₆-liposome)递送的CKIP-1 siRNA对老年绝经后骨质疏松症的治疗效果。动态活体CT分析结果表明,与0周未治疗的基础值相比,经6周治疗骨密度(BMD), 相对骨体积分数(BV/TV)和骨小梁厚度(Tb.Th)在小干扰核酸治疗组显著增加。此外,在治疗6周后小干扰核酸治疗组骨密度,相对骨体积和骨小梁厚度显示较高于模型对照组。0周与其它检测时间点之间的对比分析较显示,小干扰核酸治疗组的新生骨显著高于模型组或假手术组。组织形态学分析结果表明在治疗6周后,无论是股骨远端或中段的矿化沉积率(MAR)、骨形成速率(BFR) 和组的骨形成表面(Ob.S/ BS)在OVX组和siRNA组均显著高于模型对照组,而模型对照组和小干扰核酸治疗组的骨吸收表面(Oc.S/ BS)之间无显著性差异。 / 结论:CKIP-1基因小核酸干扰治疗在老年绝经后骨质疏松中能够显著促进骨形成并不会加剧骨吸收,该药物具有显著逆转骨丢失的作用。 / Osteoporosis is characterized by an imbalance between bone formation and bone resorption. Therefore, promoting bone formation and inhibiting bone resorption are the two major therapeutic strategies in the treatment of osteoporosis. Currently, the only Food and Drug Administration (FDA)-approved anabolic agent capable of stimulating bone formation is parathyroid hormone (PTH). However, dominant bone resorption after 18-month treatment with PTH is a great concern (Rubin and Bilezikian 2003). Thus, development of alternative bone anabolic agents is highly desirable. / Casein kinase-2 interacting protein-1 (CKIP-1), which is encoded by Plekho1, and thus also known as Plekho1, is a newly discovered negative regulator of bone formation during bone development and subsequent bone maintenance that does not activate bone resorption (Lu, Yin et al. 2008). Specifically, CKIP-1 protein functions as the auxiliary factor of ubiquitin ligase Smad ubiquitylation regulatory factor 1 (Smurf1) to interrupt the bone anabolic BMP-signalling pathway, which has been demonstrated to be a specific suppressor of bone formation (Yamashita, Ying et al. 2005). In a previous study, we found that CKIP-1 expression in female rat bone increases with aging, whereas bone formation decreases with aging (Guo, Zhang et al. 2010). Systemic examination of the tissue distribution of CKIP-1 expression has revealed that is abundantly expressed in the musculoskeletal system but sparingly expressed in the liver, lungs, kidneys, pancreas, and other organs (Zhang, Tang et al. 2007). In addition, an abnormal tissue phenotype in heart, liver, spleen, lung, and kidney tissue has not been observed in CKIP-1 gene knockout mice (KO), even at an advanced age (Lu, Yin et al. 2008). Thus, CKIP-1 gene silencing might be a potential strategy for promoting bone anabolic action in reversing bone loss. / RNA interference (RNAi), a natural cellular process that regulates gene expression by a highly precise mechanism of sequence-directed gene silencing at the stage of translation by degrading specific messenger RNA and then blocking translation of the specific gene, has been employed for gene silencing in vivo (Frank-Kamenetsky, Grefhorst et al. 2008). Accordingly, RNAi should be an appropriate target for CKIP-1 gene silencing in vivo. / We raised the hypothesis that therapeutic RNAi targeting of CKIP-1 might promote bone formation for reversing postmenopausal bone loss. To test the hypothesis, we performed several studies to achieve the following specific aims: (1) To explore the relationship between CKIP-1 expression and bone formation in aged postmenopausal osteoporosis; (2) To Identify a cross-species CKIP-1 siRNA sequence with high knockdown efficiency; (3) To validate of the identified CKIP-1 siRNA in healthy rodents in vivo; (4) To examine the anabolic effect of the identified CKIP-1 siRNA on bone in osteoporotic animal models. / The relationship between CKIP-1 gene expression and bone formation in bone specimens from aged postmenopausal women: To explore the association between CKIP-1 gene expression and bone formation in bone specimens from aged postmenopausal women, the gene expression of CKIP-1 and ALP in the bone specimens from aged female patients were examined. We found the protein expression of CKIP-1 increased during aging and negatively correlate to bone formation as indicated by the mRNA expression of ALP (Guo., Zhang. et al. 2011). Further, we also found the decreased bone formation during aging was partly rescued in Ckip-1 KO mice during aging. / A cross-species CKIP-1 siRNA sequence: Recently, we identified a specific CKIP-1 siRNA sequence (CKIP-1 siRNA si-3) with high knockdown efficiency across rat, mouse, rhesus, and human osteoblast-like cells that does not induce immunostimulatory activity and promotes osteoblast differentiation across the species in vitro and bone formation in rats in vivo (Guo, Zheng et al. 2012). / Validation of the CKIP-1 siRNA si-3 capsulated by bone-targeted siRNA delivery system in healthy rodents in vivo: We developed a bone-targeting siRNA delivery system (tripeptide aspartate-serine-serine linked with liposome, i.e. (Asp-Ser-Ser)₆-liposome) that can remarkably reduce the exposure of non-bone tissue to CKIP-1 siRNA (Zhang, Guo et al. 2012). To validate the identified CKIP-1 siRNA in healthy rodents in vivo, the established continuous CKIP-1 gene silencing protocol is optimized in adult rats and mice in vivo by hydrodynamic tail vein injection of 3.75mg/kg for rats and 7.5 mg/kg for mice every 2 weeks (Guo, Zhang et al. 2010). The osteogenic effects of CKIP-1 siRNA in both rats and mice were further validated in vivo. / Anabolic effect of CKIP-1 siRNA si-3 on bone in aged postmenopausal osteoporosis: For evaluation of the anabolic effect of CKIP-1 siRNA si-3 on reversing bone loss due to osteoporosis in an animal model, we intravenously injected ovariectomized (OVX) rats and mice with CKIP-1 siRNA delivered by the (Asp-Ser-Ser)₆-liposome, a liposome linked with six repeated aspartate-serine-serine moiety, every 2 weeks for 6 weeks. In vivo and ex vivo microCT analysis demonstrated a change over time in the variables examined and different change patterns over time among the groups examined after administration. We found that the siRNA group had experienced a significant increase in bone mineral density (BMD), relative bone volume (BV/TV), and trabecular thickness (Tb.Th) between weeks 0 and 6; had a higher BMD, BV/TV, and Tb.Th compared to the OVX group at week 6; and had a similar Tb.Th to that of the SHAM group at week 6. Registration analysis between week 0 and other time points revealed that the siRNA had a greater number of newly formed bone than the OVX and SHAM groups. Histomorphometric analysis showed that the siRNA group had a significantly higher mineralization rate (MAR), a significantly higher bone-formation rate (BFR), a significantly larger osteoblast surface (Ob.S/BS) at both the distal and mid-shaft femur compared to the OVX group after 6 weeks of treatment but not a significantly different Oc.S/BS. / Significance: Confirmation of our hypothesis by our results helps establish CKIP-1’s role as a pivotal negative regulator of bone formation in the aging skeleton and provides evidence that inhibiting CKIP-1 is a novel anabolic treatment for osteoporosis, indicating great potential for the use of therapeutic RNAi in orthopaedics and traumatology. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Guo, Baosheng. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves [132-150]). / Abstract also in Chinese. / Declaration --- p.i / Acknowledgements --- p.ii / Abstract --- p.iii / 论文摘要 --- p.vii / Table of Content --- p.ix / Abbreviations --- p.xvii / List of Figures --- p.xix / List of Tables --- p.xxii / Chapter CHAPTER 1 --- Review of recent anabolic therapy for osteoporosis --- p.1 / Chapter 1.1. --- Epidemiology of postmenopausal osteoporosis --- p.1 / Chapter 1.1.1. --- Definition of osteoporosis --- p.1 / Chapter 1.1.2. --- Epidemiology and health challenge of postmenopausal osteoporosis --- p.2 / Chapter 1.2. --- General pathophysiological understanding of osteoporosis and current challenge for osteoporosis treatment --- p.3 / Chapter 1.2.1. --- Bone modeling and remodeling --- p.3 / Chapter 1.2.2. --- Pathophysiological process of osteoporosis --- p.4 / Chapter 1.2.3. --- Systemic risk factors in the pathophysiology of osteoporosis --- p.5 / Chapter 1.2.4. --- Local risk factors in the osteoporosis pathophysiology --- p.6 / Chapter 1.2.5. --- Two therapeutic strategies for osteoporosis treatment --- p.7 / Chapter 1.3. --- Current and potential anabolic agents for osteoporosis treatment --- p.8 / Chapter 1.3.1. --- PTH analogues --- p.8 / Chapter 1.3.2. --- Potential concerns regarding PTH administration --- p.9 / Chapter 1.3.3. --- Potential PTH alternatives --- p.10 / Chapter 1.3.4. --- Modulation of Wnt/β-cateinin pathway --- p.10 / Chapter 1.3.5. --- Aptamer-based technology in osteoporosis treatment --- p.14 / Chapter 1.4. --- CKIP-1: A novel negative regulator of bone formation --- p.15 / Chapter 1.4.1. --- TGF-β/BMP signaling pathways involved in regulating bone formation --- p.15 / Chapter 1.4.2. --- CKIP-1 interrupts BMP signaling pathway --- p.16 / Chapter 1.4.3. --- CKIP-1 negatively regulates bone formation without activating bone resorption --- p.17 / Chapter 1.5. --- RNA interference strategy in anabolic therapy of osteoporosis --- p.18 / Chapter 1.5.1. --- siRNA-mediated gene silencing in osteoporosis treatment --- p.18 / Chapter 1.5.2. --- MicroRNAs as potential therapeutic targets in the anabolic treatment of osteoporosis --- p.20 / Chapter 1.5.3. --- Bone targeted RNAi-based anabolic-agents delivery --- p.23 / Chapter 1.6. --- Summary --- p.24 / Chapter CHAPTER 2 --- The relationship between CKIP-1 expression and bone formation in aged postmenopausal osteoporosis --- p.26 / Chapter 2.1 --- Introduction --- p.26 / Chapter 2.2 --- Materials and methods --- p.28 / Chapter 2.2.1 --- Bone specimen collection from aged postmenopausal women --- p.28 / Chapter 2.2.2 --- Total RNA extraction, reverse transcription and quantitative real-time PCR --- p.28 / Chapter 2.2.3 --- Total protein extraction and western blot analysis --- p.30 / Chapter 2.2.4 --- CKIP-1 expression in bone and other tissues --- p.31 / Chapter 2.2.5 --- Relationship between CKIP-1 expression and bone formation in aged ovariectomized rats --- p.31 / Chapter 2.2.6 --- Role of CKIP-1 in regulating bone formation in aged ovariectomized mice --- p.32 / Chapter 2.2.7 --- Statistics --- p.32 / Chapter 2.3 --- Results --- p.33 / Chapter 2.3.1 --- Correlation analysis between CKIP-1 expression and bone formation-related gene expression in bone specimens from agedd postmenopausal women across age --- p.33 / Chapter 2.3.2 --- CKIP-1 gene expression pattern in bone and other tissues --- p.37 / Chapter 2.3.3 --- Correlation between CKIP-1 expression and bone formation in rat bone --- p.38 / Chapter 2.3.4 --- CKIP-1 negatively regulates bone formation in aged ovariectomized mice by using CKIP-1 knockout mice --- p.39 / Chapter 2.4 --- Summary --- p.41 / Chapter CHAPTER 3 --- Identification of a cross-species CKIP-1 siRNA sequence --- p.43 / Chapter 3.1 --- Introduction --- p.43 / Chapter 3.2 --- Materials and methods --- p.44 / Chapter 3.2.1 --- Design rationale and modification for cross-species CKIP-1 siRNA --- p.44 / Chapter 3.2.2 --- In vitro screening for cross-species CKIP-1 siRNA sequences --- p.45 / Chapter 3.2.3 --- Investigation of the effects of the identified CKIP-1 siRNA on the expression of osteoblast phenotype genes --- p.47 / Chapter 3.2.4 --- Total RNA extraction, reverse transcription and quantitative real-time PCR --- p.47 / Chapter 3.2.5 --- Western blot analysis --- p.51 / Chapter 3.2.6 --- Evaluation of calcium deposition --- p.51 / Chapter 3.2.7 --- BMP-2 reporter activity assay in MC3T3-E1 cells --- p.52 / Chapter 3.2.8 --- Isolation of the primary human blood monocytes and IFN-α and TNF-α measurement --- p.53 / Chapter 3.2.9 --- Statistics --- p.54 / Chapter 3.3 --- Results --- p.54 / Chapter 3.3.1 --- Bio-informatic analysis of the designed CKIP-1 siRNA sequences --- p.54 / Chapter 3.3.2 --- Identified the cross-species CKIP-1 siRNA sequences by In vitro screening --- p.56 / Chapter 3.3.3 --- Effects of the identified CKIP-1 siRNA on the expression of osteoblast phenotype genes --- p.60 / Chapter 3.3.4 --- Effects of the identified CKIP-1 siRNA on matrix mineralization --- p.65 / Chapter 3.3.5 --- Effect of the identified CKIP-1 siRNA on BMP signaling --- p.67 / Chapter 3.3.6 --- Effects of the identified CKIP-1 siRNA on the ratio of RANKL/OPG --- p.67 / Chapter 3.3.7 --- Effects of the identified CKIP-1 siRNA on immunostimulatory activity --- p.68 / Chapter 3.4 --- Summary --- p.71 / Chapter 3.4.1 --- CKIP-1 siRNA si-3 as the identified sequence --- p.71 / Chapter 3.4.2 --- CKIP-1 siRNA si-3 promoted osteoblast differentiation in vitro --- p.72 / Chapter CHAPTER 4 --- Validation of the identified CKIP-1 siRNA in healthy rodents in vivo --- p.74 / Chapter 4.1 --- Introduction --- p.74 / Chapter 4.2 --- Materials and methods --- p.74 / Chapter 4.2.1 --- Localization of intraosseous siRNA delivered by (Asp-Ser-Ser)₆-liposome --- p.75 / Chapter 4.2.2 --- Cell-selective delivery in vivo of CKIP-1 siRNA --- p.76 / Chapter 4.2.3 --- Dose-response study of CKIP-1 siRNA --- p.77 / Chapter 4.2.4 --- Time-course study of CKIP-1 siRNA --- p.77 / Chapter 4.2.5 --- Examination of the effect of the identified siRNA on the expression of osteoblast phenotype genes --- p.78 / Chapter 4.2.6 --- Measurement for serum PINP and urinary DPD --- p.80 / Chapter 4.2.7 --- 5’-RACE Analysis --- p.81 / Chapter 4.2.8 --- Laser captured micro-dissection (LCM) --- p.82 / Chapter 4.2.9 --- Evaluation the anabolic effect of the identified siRNA on healthy rat bone --- p.82 / Chapter 4.2.10 --- Evaluation the anabolic effect of the identified siRNA on healthy mouse bone --- p.84 / Chapter 4.2.11 --- Micro CT analysis --- p.84 / Chapter 4.2.12 --- Dynamic bone histomorphometric analysis --- p.85 / Chapter 4.2.13 --- Statistics --- p.86 / Chapter 4.3 --- Results --- p.87 / Chapter 4.3.1 --- Rationale of bone targeted delivery of CKIP-1 siRNA by (Asp-Ser-Ser)₆-liposome --- p.87 / Chapter 4.3.2 --- Intraosseous distribution of siRNA delivered by (Asp-Ser-Ser)₆-liposome --- p.89 / Chapter 4.3.3 --- Optimal dosage and duration for CKIP-1 siRNA administration in vivo --- p.92 / Chapter 4.3.4 --- Knockdown efficiency of CKIP-1 siRNA in osteoblasts by LCM in combination with Q-PCR --- p.94 / Chapter 4.3.5 --- Examination of the effect of the identified siRNA on the expression of osteoblast phenotype genes --- p.96 / Chapter 4.3.6 --- RNAi mechanism of CKIP-1 siRNA action in vivo --- p.99 / Chapter 4.3.7 --- Anabolic effect of the identified siRNA on healthy rat bone --- p.101 / Chapter 4.3.8 --- Anabolic effect of the identified siRNA on healthy mouse bone . --- p.104 / Chapter 4.4 --- Summary --- p.107 / Chapter 4.4.1 --- Intraosseous localization of CKIP-1 siRNA after systemic administration --- p.107 / Chapter 4.4.2 --- Evidence of RNAi in bone tissue from systemic administration of CKIP-I siRNA --- p.107 / Chapter 4.4.3 --- CKIP-1 siRNA si-3 promots bone formation in rats and mice in vivo --- p.108 / Chapter CHAPTER 5 --- Anabolic effect of the identified CKIP-1 siRNA on bone in postmenopausal osteoporostic animal models --- p.110 / Chapter 5.1. --- Introduction --- p.110 / Chapter 5.2. --- Materials and Methods --- p.110 / Chapter 5.2.1. --- Evaluation of anabolic effect of CKIP-1 siRNA on osteoporotic mouse bone --- p.111 / Chapter 5.2.2. --- Evaluation of anabolic effect of CKIP-1 siRNA on osteoporotic rat bone --- p.112 / Chapter 5.2.3. --- In vivo micro-CT analysis and registration of proximal tibia from osteoporotic rats --- p.112 / Chapter 5.2.4. --- Ex vivo micro-CT analysis of the distal femur and 5th lumbar vertebrae body of osteoporotic rats --- p.115 / Chapter 5.2.5. --- Ex vivo micro-CT analysis of distal femur from osteoporotic mice --- p.115 / Chapter 5.2.6. --- Bone histomorphometric analysis --- p.116 / Chapter 5.2.7. --- Mechanical testing --- p.117 / Chapter 5.2.8. --- Statistics --- p.118 / Chapter 5.3. --- Results --- p.116 / Chapter 5.3.1. --- Anabolic effect of CKIP-1 siRNA si-3 on osteoporotic mouse bone --- p.118 / Chapter 5.3.2. --- In vivo microCT data of proximal tibia from aged osteoporotic rats --- p.121 / Chapter 5.3.3. --- Ex vivo microCT data of distal femur from aged osteoporotic rats --- p.124 / Chapter 5.3.4. --- Ex vivo microCT data of 5th LV body from aged osteoporotic rats --- p.126 / Chapter 5.3.5. --- Bone histomorphometric analysis of aged osteoporotic rats --- p.129 / Chapter 5.3.6. --- Mechanical testing of the mid-shaft femur of aged osteoporotic rats --- p.132 / Chapter 5.4. --- Summary --- p.134 / Chapter CHAPTER 6 --- Discussions --- p.134 / Chapter 6.1 --- CKIP-1 siRNA design rationale and further modification --- p.135 / Chapter 6.1.1 --- Specificity design rationale of the CKIP-1 siRNA --- p.135 / Chapter 6.1.2 --- Stability enhancing modification of CKIP-1 siRNA --- p.136 / Chapter 6.1.3 --- Safety concerns with CKIP-1 siRNA therapy --- p.136 / Chapter 6.2 --- Development of bone-targeted siRNA delivery --- p.136 / Chapter 6.3 --- Prospects for and limitation of application of study findings to clinical therapeutics --- p.137 / References --- p.139 / Publications --- p.159
148

Roles of cellular FLICE-inhibitory protein (c-FLIP) and Pl3K/Akt in Fas (CD95)-induced NF-[kappa]B activation and apoptosis through death effector domains

Lu, Bin, January 2005 (has links)
Thesis (Ph. D.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains viii, 95 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 82-95).
149

Interaction of CFTR with AF-6/afadin and Its functional role in colorectal cancer metastasis. / CUHK electronic theses & dissertations collection

January 2012 (has links)
CFTR基因突變或者功能缺失是否導致包括胃腸道在內的各種組織惡性腫瘤的發生風險增加目前仍然是一個充滿爭議的問題。同時,眾所周知,緊密連接分子在腫瘤發生和轉移的過程發揮了關鍵的作用。本論文首次發現了CFTR基因與一種緊密連接分子AF-6/afadin的在人類結直腸腫瘤中的表達水平呈高度相關,并研究了CFTR和AF-6/afadin之間潛在的相互作用及其在結直腸腫瘤轉移中的功能。 / 論文的第一部份首先用實時定量PCR和免疫組織化學的方法比較了CFTR在結直腸腫瘤和正常組織的表達情況,發現CFTR表達水平在腫瘤組織中有顯著的下降。令人感興趣的是,我們同時發現CFTR和AF-6/afadin在腫瘤組織中的表達呈高度正相關,并由此展開了後續的體外實驗,研究對CFTR與AF-6/afadin之間可能的相互聯繫。利用免疫螢光染色和免疫共沉澱的方法,我們發現了這兩種蛋白分子共表達在結直腸腫瘤細胞的接觸面,并存在相互作用。用CFTR突變蛋白的免疫共沉澱實驗進一步發現,這種相互作用需要CFTR分子在細胞膜表面的正確定位及其PDZ結構域結合位點。實驗還發現與CFTR的相互作用加強了AF-6/afadin與細胞骨架蛋白系統的結合。在結直腸腫瘤細胞中CFTR基因敲减导致了AF-6/afadin蛋白定位混亂,從細胞連接位點轉移到細胞漿內,并因此破壞了上皮細胞的緊密性。極性生長細胞的跨上皮電阻降低而滲透性增強的實驗結果證實了CFTR基因敲減導致的上皮細胞緊密性的破壞。同時,AF-6/afadin蛋白水平也隨著CFTR基因敲減而降低,但mRNA水平未發生明顯的改變。蛋白降解系統的抑製劑逆轉了CFTR基因敲減細胞中AF-6/afadin蛋白的減少,提示CFTR基因敲減增加了AF-6/afadin的蛋白降解。這些實驗結果揭示了通過與細胞連接分子AF-6/afadin的相互作用以及調節,CFTR可能在上皮細胞極性的調節以及腫瘤發展過程中起重要作用。 / 論文的第二部份研究了CFTR和AF-6/afadin在結直腸腫瘤細胞上皮細胞間充質化(EMT)和轉移過程中的功能及機制。我們之前的工作已經揭示抑制CFTR的功能可以誘導結直腸腫瘤LIM1863細胞的EMT過程。本研究在另外三株不同的結直腸腫瘤細胞(SW480,SW1116和HRT-18)中進一步證實了抑制CFTR誘導的EMT過程。細胞形態轉變,上皮細胞標誌物的下調,間充質細胞標誌物的上調以及受損的上皮細胞緊密性均證實了對CFTR的抑制可以在這三種細胞中成功誘導EMT的發生。我們發現在以上所有細胞EMT的過程中,AF-6/afadin的蛋白表達水平都發生了顯著的下調。在HRT-18細胞中過表達AF-6/afadin,可以逆轉由CFTR抑製劑誘導的上皮細胞標誌分子的下調和間充質標誌分子的上調,表明抑制CFTR誘導的EMT過程是由AF-6/afadin參與介導的。此外,CFTR基因敲減導致結直腸腫瘤細胞的惡性表型強化,包括減弱的細胞粘附性,增強的貼壁依賴性生長、侵襲和遷移。另外,CFTR基因敲減激活了ERK的磷酸化,過表達AF-6/afadin可以阻斷ERK途徑的激活。CFTR基因敲減而增強的細胞侵襲性也可以被外源性AF-6/afadin或者ERK途徑的抑製劑U0126完全逆轉,提示作為AF-6/afadin的下游靶信號,ERK介導了CFTR在腫瘤侵襲中的作用。更重要的是,我們分析了CFTR和AF-6/afadin的表達水平與結直腸癌病人腫瘤進展的關係,發現在嚴重TNM腫瘤分期或者有腫瘤遠處轉移的病人中CFTR的表達水平顯著低於輕型分期或未发生转移的病人中的水平,而且CFTR和/或AF-6/afadin低表達的病人的預後更差。這些實驗結果顯示CFTR的缺失可能通過抑制AF-6/afadin和激活ERK通路而與EMT和結直腸癌癥轉移的過程高度相關。 / 綜上所述,本研究揭示了以往未報道過的CFTR在結直腸腫瘤發病機理中的功能,提示CFTR可以用作一種新的腫瘤的潛在預後指標。 / The question whether mutation or dysfunction of CFTR increases the risk of malignancies in various tissues, including the gastrointestinal tract, remains highly controversial. Meanwhile, it is well-known that adherens junctions play critical roles in the process of cancer development and metastasis. In this thesis we found for the first time a highly correlation between expression levels of CFTR and an adherens junction molecule AF-6/afadin in human colorectal tumours, and investigated the potential interaction between CFTR and AF-6/afadin and their functional roles in the metastasis of colorectal cancer. / In the first section of this thesis, we started our studies with comparing the expression of CFTR between human colorectal tumours and normal colorectal tissues. Real time quantitative PCR and immunohistochemistry results revealed a dramatically reduced CFTR level in the cancer tissues. Intriguingly, we noticed a highly positive correlation between CFTR and AF-6/afadin expression in tumours, which prompted the further in vitro investigation of possible interaction between CFTR and AF-6/afadin. Using immunofluoresent staining and co-immunoprecipitation, we found that the two proteins were colocalized at cell-cell junctions and interacted with each other in colorectal cancer cell lines. Further Co-IP experiments performed with CFTR mutations revealed that this protein interaction requires the proper localization of CFTR in cell membrane and its PDZ-interacting domain. Moreover the interaction with CFTR strengthens the binding of AF-6/afadin to the cytoskeleton system. Knockdown of CFTR in colorectal cancer cells resulted in the disorganized localization of AF-6/afadin protein from junctional sites to the cytoplasm and impaired epithelial tightness, which was confirmed by significantly reduced transepithelial resistance and increased permeability of polarized cells. Meanwhile, the protein level of AF-6/afadin was down-regulated in CFTR-knockdown cells, while no significant changes were detected at the mRNA level. Protein degradation inhibitor reversed the repression of AF-6/afadin protein in CFTR knockdown cells, suggesting the protein degradation of AF-6/afadin was increased by CFTR knockdown. These data revealed that CFTR interacts with and regulates the cell adhesion molecular AF-6/afadin in colorectal cells, which may be important in the regulation of epithelial cell polarity and cancer development. / In the second section of this thesis, we studied the functional roles and mechanisms of CFTR and AF-6/afadin in the epithelial-mesenchymal transition (EMT) and metastasis of human colorectal cancer cells. Our previous work has revealed inhibition of CFTR can induce EMT in a colorectal cancer cell line, LIM1863. This study further confirmed the induction of EMT by inhibiting CFTR in several other colorectal cancer cell lines (SW480, SW1116 and HRT-18), which was evaluated by morphological changes, down-regulation of epithelial markers or up-regulation of mesenchymal markers, and impaired epithelial cell tightness. In all these cell lines, we found that the protein levels of AF-6/afadin were significantly reduced. Over-expression of AF-6/afadin in HRT-18 cells reversed the down-regulated epithelial markers and up-regulated mesenchymal markers induced by CFTR inhibition, indicating that the CFTR inhibition-induced EMT is mediated by AF-6/afadin. Moreover, knockdown of CFTR in HRT-18 or RKO cells resulted in enhanced malignant phenotypes, including decreased cell adhesion, increased anchorage-independent cell growth, invasion, and migration. In addition, extracellular signal-regulated kinase (ERK) phosphorylation was activated by CFTR knockdown, which was abolished by over-expression of AF-6/afadin. The enhanced invasiveness of CFTR knockdown cells was also completely inhibited by either exogenous AF-6/afadin or ERK inhibitor, U0126, suggesting that ERK, the downstream target of AF-6/afadin, is involved in mediating the effect of CFTR in cancer invasion. More importantly, we analyzed the association of CFTR and AF-6/afadin expression levels with tumour progression of patients with colorectal cancer, and revealed that CFTR expression was significantly lower in patients with more severe TNM stage or with metastasis to distant organs than those with milder stage or with no metastasis. The prognosis was poorer in patients with lower expression of CFTR and/or AF-6/afadin than those with higher expressions. These data showed that dysfunction of CFTR is highly associated with EMT and colorectal cancer metastasis, probably via repression of AF-6/afadin and activation of ERK pathways. / In summary, the present study has revealed a previously undefined role of CFTR in the pathogenesis of colorectal cancer and indicated its potential as a new prognostic indicator. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Sun, Tingting. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 113-127). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Abstract --- p.i / 中文摘要 --- p.iv / Publications --- p.vi / Conference Abstract --- p.vii / Declaration --- p.viii / Acknowledgements --- p.x / List of Figures --- p.xi / List of Tables --- p.xiii / List of Abbreviations --- p.xiv / Chapter Chapter 1 --- General Introduction --- p.1 / Chapter 1.1. --- Colorectal Cancer --- p.1 / Chapter 1.1.1. --- Structure of Human Normal Colon and Rectum Epithelium --- p.1 / Chapter 1.1.2. --- Staging of Colorectal Cancer --- p.3 / Chapter 1.1.3. --- Metastasis of Colorectal Cancer --- p.3 / Chapter 1.1.4. --- K-Ras mutation and It Downstream Pathways in Colorectal Cancer Metastasis --- p.11 / Chapter 1.1.5. --- Prognosis of Colorectal Cancer --- p.14 / Chapter 1.2. --- Epithelial Cell Junctional Complexes --- p.14 / Chapter 1.2.1. --- Junctional Complexes and Epithelial Cell Polarity --- p.15 / Chapter 1.2.2. --- Classic Cadherin-catenin Complex --- p.17 / Chapter 1.2.3. --- Novel Nectin-afadin Complex --- p.19 / Chapter 1.2.4. --- Cell Polarity and Cancer Progression --- p.23 / Chapter 1.3. --- Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) --- p.24 / Chapter 1.3.1. --- Structure of CFTR --- p.24 / Chapter 1.3.2. --- Mutations of CFTR --- p.24 / Chapter 1.3.3. --- Functions of CFTR --- p.26 / Chapter 1.3.4. --- Cancer Risk of CF Patients --- p.33 / Chapter 1.4. --- Hypothesis and Aims --- p.34 / Chapter Chapter 2 --- Materials and Methods --- p.35 / Chapter 2.1. --- Materials --- p.35 / Chapter 2.1.1. --- Reagents and Chemicals --- p.35 / Chapter 2.1.2. --- Antibodies --- p.35 / Chapter 2.1.3. --- Primers --- p.35 / Chapter 2.1.4. --- Solutions and Buffers --- p.35 / Chapter 2.1.5. --- Human Specimens --- p.36 / Chapter 2.2. --- Methods --- p.36 / Chapter 2.2.1. --- Cell Culture --- p.36 / Chapter 2.2.2. --- Transfection --- p.36 / Chapter 2.2.3. --- Selection of Stable Clones --- p.40 / Chapter 2.2.4. --- RNA Extraction and RT-PCR --- p.40 / Chapter 2.2.5. --- Quantitative Real Time PCR --- p.41 / Chapter 2.2.6. --- Protein Extraction and Western Blotting --- p.42 / Chapter 2.2.7. --- Immunostaining --- p.45 / Chapter 2.2.8. --- In vitro Cell Functional Assays --- p.46 / Chapter 2.2.9. --- Epithelial Tightness Measurement --- p.48 / Chapter 2.2.10. --- Statistical Analysis --- p.49 / Chapter Chapter 3 --- Interaction of CFTR with AF-6/afadin and Its Importance in Maintaining Colorectal Epithelial Cell Polarity --- p.50 / Chapter 3.1. --- Introduction --- p.50 / Chapter 3.2. --- Objectives --- p.53 / Chapter 3.3. --- Experimental plan --- p.54 / Chapter 3.4. --- Results --- p.55 / Chapter 3.4.1. --- The expression of CFTR and AF-6/afadin is decreased and positively correlated in human colorectal cancer --- p.55 / Chapter 3.4.2. --- CFTR colocalizes and interacts with AF-6/afadin in human colorectal cancer cells --- p.58 / Chapter 3.4.3. --- PDZ binding motif and membrane localization of CFTR are necessary for the interaction between CFTR and AF-6/afadin --- p.64 / Chapter 3.4.4. --- Knockdown of CFTR interferes with cell junction formation in colorectal cancer cells --- p.66 / Chapter 3.5. --- Discussion --- p.71 / Chapter Chapter 4 --- CFTR as a Suppressor and Prognosis Indicator of Metastasis in Human Colorectal Cancer --- p.77 / Chapter 4.1. --- Introduction --- p.77 / Chapter 4.2. --- Objectives --- p.80 / Chapter 4.3. --- Experimental plan --- p.81 / Chapter 4.4. --- Results --- p.82 / Chapter 4.4.1. --- CFTR inhibition-induced EMT in colorectal cancer cells involves AF-6/afadin --- p.82 / Chapter 4.4.2. --- Knockdown of CFTR aggravates malignant phenotype of colorectal cancer cells --- p.86 / Chapter 4.4.3. --- AF-6/afadin mediates the effect of CFTR on cell invasion in colon cancer through ERK --- p.91 / Chapter 4.4.4. --- CFTR and AF-6/afadin expression is correlated with the prognosis of colorectal cancer --- p.97 / Chapter 4.5. --- Discussion --- p.100 / Chapter Chapter 5 --- General Discussion and Conclusion --- p.105 / Chapter 5.1. --- The diversified roles of CFTR in epithelial cells --- p.105 / Chapter 5.2. --- The unfolding relationship between CFTR and cancer development --- p.107 / Chapter 5.3. --- Future studies --- p.109 / Chapter 5.4. --- Conclusions --- p.112 / Reference List --- p.113 / Chapter Appendix A --- Reagents and Chemicals --- p.128 / Chapter Appendix B --- Antibody List --- p.131 / Chapter Appendix C --- Primer List --- p.132 / Chapter Appendix D --- Solution Recipe --- p.133
150

Molecular characterization of the fepA-fes bidirectional promoter in escherichia coli

Morris, Terry Lynn, January 2001 (has links)
Thesis (Ph. D.)--University of Missouri--Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 135-149). Also available on the Internet.

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