The transition metals iron and zinc are essential requirements for all living organisms. They participate in a variety of critical metabolic pathways, enzymatic activity, and provide structural support for countless proteins. Metal ion imbalance can be detrimental to organisms, as metal deficiency can alter many biological processes while metal excess can lead to toxicity. To alleviate these detrimental situations, the yeast Saccharomyces cerevisiae has developed tightly controlled regulatory mechanisms for the proper expression of proteins that control import, export, and storage of these essential metals. This regulation is required to ensure the efficient uptake, transport, and storage of specific metal ions during periods of metal concentration fluctuations.

The work presented in the first chapter of this dissertation identifies the use of cryptic transcription as a means for regulatory control of the subtelomeric metal genes ZRT1 and FIT3. These transcripts arise from promoter units upstream of the ZRT1/FIT3 transcription unit and extend into the open reading frame (ORF). We show that these transcripts are degraded by the cytoplasmic Non-Sense Mediated Decay (NMD) Pathway and are only stabilized in the absence of the NMD Pathway; hence termed Cytoplasmically Degraded Cryptic Unstable Transcripts (CD-CUTs). We further show that these CD-CUTs act to prevent expression of ZRT1 by interfering with RNA polymerase II binding and activator binding (Zap1p) to the ZRT1 promoter unit.

As we identified the use of CD-CUTs to mediate the repression of ZRT1/FIT3 during normal zinc/iron conditions, the mechanistic mode of action of these transcripts remained elusive. In an attempt to identify how a cytoplasmically degraded transcript can mediate transcription in the nucleus, we chose to study the cytoplasmic trafficking of these species. In chapter two, we show that the export of the ZRT1/FIT3 CD-CUTs is likely mediated by the SR-type mRNA export factor Hrb1p and dependent on the essential mRNA export factor Mex67p.

Lastly, we identify an additional mode of regulation for the iron transport gene FIT3 by the glucose repressor Mig1p. Mig1p has been extensively characterized as a repressor of glucose responsive genes and in chapter three, we show that this regulation can be applied to iron regulation. We believe that Mig1p regulates the repression of FIT3 during conditions of normal iron and/or after switch back to normal iron conditions following iron starvation to prevent the deleterious expression of FIT3, thereby preventing the potentially harmful effects of iron toxicity.

This study focuses on the corporate welfare provided by the US government to corporations despite their high profits and argues that the significant and negative consequences to the federal and state tax bases of such welfare make it a state corporate crime. Failure to stabilize or rollback corporate welfare initiatives has resulted in a significant decrease in the percentage of federal and state revenue that comes from corporate tax contributions. I use structural equation modeling to analyze the consequences of corporate welfare initiatives on the federal tax base and the California state tax base. Drawing insights from an integrated theory of state-corporate crime developed by Kauzlarich and Kramer (1998), I examine various forms of deviance and collusion between corporations and the federal government. Specifically, this study explores this collusion on two levels: the structural and organizational levels. That is, I focus on the period before, during and after the implementation of corporate welfare initiatives and the organizational environment of the two groups involved. This study reveals that the federal government facilitated state corporate crime in this case by continuing to provide tax breaks, investment incentives, and loans to corporations despite the high yield in corporate profits, declining corporate tax contributions, high delinquency rates on loans, and the continuous outsourcing of jobs. Because of the lack of government oversight, or deregulation, corporations were able to take advantage of the tax-exempt restructuring offered by the Tax Reform Act of 1986 and Revenue Act of 1987, and tax credits beginning with Economic Recovery Act of 1981. This resulted in social harms that were associated with declining tax contributions to state and federal governments, namely a growing deficit, cutbacks in vital social services, and an increased tax burden among individual taxpayers.

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