Regulation of Gene Expression: Molecular Mechanisms presents a comprehensive overview of methods and approaches for characterizing mechanisms of gene regulation. The text is appropriate both as a graduate textbook and a standard laboratory reference and provides the essential groundwork for an advanced understanding of the various mechanisms that may result in altered activity of a specific cell protein. Each of three sections explores mechanisms of gene regulation and expression, and presents methods and protocols for achieving specific experimental goals. Part I focuses on approaches for studying control of mRNA expression and determining target genes for a given transcription copy. Part II outlines the methods for determining how proteins can regulate each other by mediating synthesis, degradation, protein-protein interactions, and posttranslational modification. Part III explores how gene targeting techniques in mice can provide insight into protein function. This volume provides a clear, concise overview of the protocols and techniques used to examine chemically or disease-mediated alterations in gene expression in mammalian systems.