Type IV collagens are components of basement membranes throughout the body and are involved in maintenance of the structural integrity of tissues as well as cellular differentiation, growth, and adhesion. Members of this collagen family are uniquely arranged in pairs in a head-to-head orientation and share a proximal promoter region. The COL4A5-COL4A6 gene pair is involved in numerous human diseases and cancer metastasis. For these reasons, defining the mechanisms that regulate collagen gene expression is of specific interest. To study type IV collagens, an in vitro model system was characterized. Comparative genomics was utilized to identify conserved, non-coding DNA in COL4A5 and COL4A6. These sequences were transfected into cell lines differing in type IV collagen expression and tested for the ability to regulate transcription of a reporter gene. Each cell line was also treated with the epigenetic modifying agents, 5-Aza and TSA. The effects on type IV collagen expression were determined. The COL4A5-COL4A6 promoter region was extensively characterized using ChIP analysis; antibodies against RNAPII, acetylated histone H3, and H3K9me2 were used. Additionally, bisulfite sequencing was carried out on each cell line to determine the methylation status of CpG dinucleotides in the promoter. Cell lines differing in expression of COL4A5 and COL4A6 were identified: 1) SCC-25 keratinocytes and HEK-293 cells transcribed both COL4A5 and COL4A6, 2) HT-1080 cells selectively activated COL4A5, and 3) SK-N-SH neuroblastoma cells did not express either gene. In SK-N-SH cells, histone modifications were shown to facilitate formation of condensed chromatin to prevent transcription initiation; repression was independent of DNA methylation. Activation of COL4A5 and COL4A6 in SCC-25 and HEK-293 cells involved acetylation of histones, although differences between the two cell types were seen. In addition, conserved, non-coding sequences were shown to affect transcription of a reporter gene; these sequences may be interacting with the transcription machinery to modulate collagen expression. Finally, repression of COL4A6 in HT-1080 cells appeared to be mediated through DNA methylation of the promoter; selective activation of COL4A5 may involve conserved, non-coding DNA. In summary, epigenetic modifications as well as conserved sequences are intimately involved in regulation of type IV collagen gene expression.

Brucella melitensis is the etiological agent of brucellosis, a zoonotic disease characterized by abortions in ruminant animals and a chronic debilitating disease in humans. Despite genome sequencing, little is known about the genetic elements behind Brucella s ability to survive and cause disease. Regulatory networks provide the ability to adapt to changing environments by initiating expression from specific regulons to provide adjustments to metabolism and mechanisms that enhance survival. Little detail is known about transcriptional networks that exist in Brucella, but are of great interest because they could provide information about genetic loci that contribute to virulence and intracellular survival. Transposon mutagenesis identified gene loci that are indispensable for the intracellular replication of B. melitensis, including virulence genes, metabolic defects, and transcriptional regulators. Two transcriptional regulators of interest were identified, MucR and VjbR. VjbR is a LuxR homologue and is associated with the regulation of virulence genes in a density dependent manner in a number of bacterial pathogens, and is consistent with VjbR regulation of virulence genes in B. melitensis. Microarray analysis of vjbR and a potential activating signal C12-HSL revealed that both regulate numerous putative virulence genes, including adhesins, proteases, protein secretion/translocation components, potential effector proteins, lipoproteins, a hemolysin and stress survival aids. This analysis also revealed that C12-HSL is not an activating signal of VjbR, but instead acts to suppress VjbR activity. MucR is a transcriptional regulator shown to regulate exopolysaccharide synthesis in the closely related Rhizobiales. Microarray analysis of a mucR mutant in B. melitensis suggested that MucR contributes to the regulation of nitrogen metabolism and iron sequestering/storage. MucR was also found to regulate genes involved in stress response, regulating several proteases that may contribute to enhanced survival and virulence of the organism. This work identified approximately 1,000 genetic loci that may be important to the survival of B. melitensis, revealing potential virulence genes and metabolic defects. Interruption of the VjbR regulon could be a potential chemotherapeutic target for the treatment of brucellosis. Furthermore, this work describes the functions of two gene deletions that are being evaluated as novel attenuated vaccines.

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Abstract As the result of the free economic booming in the past years, th international trade relations have became more closed and intense. Especially, the globlization and WTO make most of the industries become more competitive. Each government takes reformation at the industry movement¡Bprivatization or free economy policy to achieve the cost down and efficiency in order to obtain international marketing advantage .for example,the British government was the first one todeploy privatizatiopn of electricity market Since 1980 .Its successful is the pattern of American¡AAustrian¡Anorth Europe and Asia countries. The electricity market is monopolized by the governent-own Taiwan Power Company for more than 50 years.It has the traditional bussinesss including the power generation¡Bthe transmission ¡Bthe distribution and the sales ,which made excellent contribution to this country. After 1980s¡Awith global economic booming¡A the electricity power demanding is gradually impeded by green party and public that corncern the impact to the environment verywhere on this island. Consequently ,without the sufficient power supply ,the electricity power shortage was quite often since then.In order to facilitate the efficient management and increase the capacity of the power the government ordered the Department of Economy of ROC to accomplish the de-regulation and privatization of the electricity market.By induced the capital with management skill from local private company¡Athe goal has been achieved with significant progresses.and more competitors.Three stages bid increased 9000 mw of power at final¡Ait nearly 25¢Mof total market, four privates power company was synconization already since 1998. Generally speaking ,the power deregulation policy is successful and has been gradually move to its target. The beginning of this paper is to probe the difficulties that the private-owned company ,though the planning, to the final achievement. By collecting and investigating all the related materials, this paper discusses and reviews the drawback and results of the power deregulation policy. And the main topics are to provide the advise and create new vision for the undergoing deregultion plan ,including the analysis and review of the privatization policy ,the location decision of new power plans the planning and design for the power distribution ,ande marketing of the electricity. The private power companies could use the final conclusionas the advice or references in their future plans

The master insurance institution of Mainland China has been changed for a long time and keeps close relationship with the different insurance policy, which was advocated by the government in every period. At first, the nation takes charge of the insurance enterprise comprehensive, afterwards, the circumstance change into the situation of the social insurance as the principal thing and the business insurance is an assistant. On account of Mainland China insurance inspection system was undertook later than the insurance market was formed, therefore, the inspection way was unable to catch up with the rapid development of the insurance enterprise. Further, the whole inspection system lie in passive state from beginning to end which resulted from the staff of the inspection organization was insufficient. The investigative motive of this summary is for search into the development process and present situation of Mainland China insurance market, in addition, seek for the basic reformation which come into existence, after Mainland China joined WTO. This summary relevant to the subject from Mainland China insurance enterprise organization and take the insurance organizied system and standard as analysis foundation and take historical aspect, realistic aspect, and future aspect to make a vertical arrangement and analysis.

The metal-responsive transcriptional repressors of the SmtB/ArsR family repress the expression of their respective operons in the absence of metal and are released from the operator/promoter region when metal ions bind, thus allowing RNA polymerase to bind and transcribe the operon, which encodes genes involved in homeostasis and resistance. To elucidate the determinants of metal ion selectivity, comparative metalbinding and DNA-binding properties of S. aureus CzrA and M. tuberculosis NmtR were characterized. The structure of the metal coordination complexes of CzrA and NmtR reveal that CzrA forms a 4-coordinate, tetrahedral complex with both Zn(II) and Co(II) potent regulators of czr operator/promoter (O/P) binding in vitro and de-repression in vivo. In contrast, NmtR adopts 5- or 6-coordinate complexes with Ni(II) and Co(II), the strongest allosteric regulators of nmt O/P binding in vitro and de-repression in vivo. Zn(II), a non-inducer in vivo and poor regulator in vitro, binds NmtR with high affinity and forms a non-native 4-coordinate complex. These studies suggest that metal coordination geometries (number), not metal binding affinities, are primary determinants of functionality. To gain molecular insight into the mechanism of allosteric regulation of O/P binding by metal ions, NMR and X-ray crystallographic studies of apo- and zinc forms of CzrA, and another ArsR/SmtB zinc sensor, Synechococcus PCC7942 SmtB, were performed. These studies showed that formation of the metal chelate drives a quaternary structural switch mediated by an intersubunit hydrogen-binding network that originates with the nonliganding Nε2 face of His97 in CzrA (His117 in SmtB) that stabilizes a low affinity DNA-binding conformation. Mutagenesis experiments reveal that substitution of D84 and H97 in CzrA, results in the formation of higher coordination number complexes that are nonfunctional in driving zinc-mediated allosteric regulation of DNA binding. In contrast, conservative mutations of H86 and H100 in CzrA bind Co(II) or Zn(II) in a tetrahedral manner, albeit with greatly reduced affinity, and allosterically regulate O/P binding with significant lower coupling free energies compared to wild-type CzrA. These findings further reinforce the notion that metal coordination geometry is the primary determinant for functional sites in metal-sensing transcriptional repressors.

Two experiments compared the effects of two cognitive responses (i.e., rumination and cognitive reappraisal) individuals may adopt when confronted with a threat to self-regard. In Study 1, participants received negative feedback about their social skills and then rated the credibility of the source of the criticism. In Study 2, participants received negative feedback and then were given the opportunity to enhance the self on an unrelated task. Compared to reappraising the negative feedback, ruminating about the feedback led to poorer evaluations of the source of negative feedback and increased self-enhancement, respectively. These findings suggest that, compared to rumination, cognitive reappraisal helps to minimize defensive responses to ego threat.

Eidgen. Techn. Hochschule, Diss.--Zürich, 2006.

Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from UMI/Dissertation Abstracts International.

Thesis--PlanB (M.S.)--University of Wisconsin--Stout, 2002. / Includes bibliographical references.