S-40 Stress Responses via Metallothioneins: Roles in the Biological Defense Mechanism   S40-1. Heavy Metal Responses of Human Metallothionein Isoform Genes   S40-2. Mechanism of Metallothionein Gene Activation Mediated by Heavy-Metal Dependent Transcription Factor MTF-1   S40-3. Cytokine-Induced Expression of Metallothionein and Modulation of Cytokine Expression by Metallothionein   S40-4. The Physiological Significance of Metallothionein in Oxidative Stress   S40-5. Endoplasmic Reticulum Stress and Metallothionein   S40-6. Analysis of Toxicity Using Metallothionein Knockout Mice