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Discover the role of histone patterns in cell-specific gene expression. Learn the impact of transcription factors & regulatory regions on gene accessibility. Explore signal transduction pathways like interferon-γ activation.
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13. TF TF Cell-specific gene expression Skin cells gene 1 P1 Ex1 Ex2 T I1 I2 Ex3 Skin cell-specific enhancer S gene 2 Ex1 I1 P2 Ex2 Ex3 T I2 I3 Ex4 Neuron-specific enhancer Nerve cells gene 1 P1 Ex1 Ex2 T I1 I2 Ex3 Skin cell-specific enhancer gene 2 Ex1 I1 P2 Ex2 Ex3 T I2 I3 Ex4 Neuron-specific enhancer Cell-specific gene expression: histone pattern! 1. Type of transcription factor expressed in a cell 2. The accessibility of the regulatory region of a gene
Signal transduction Steroid hormone activation inhibitor (hsp90) steroid glucocorticoid receptor Nucleus DNA GRE cytoplasm GRE: glucocorticoid response element
Signal transduction Interferon-γ activation IFN-γ IFN-γ receptor P P JAK kinase STAT-1 nucleus DNA RE RE: response element IFN: interferon JAK: Janus activated kinase STAT-1: transcription factor cytoplasm
1 siRNA: small interfering RNA RISC: RNAi silencing complex RISC*: activated RISC Slicer: it cleaves mRNA RNase: ribonuclease RNA interference – Dicing Dicer Double-stranded RNA siRNAs (21-23 base pairs) RISC Helicase RISC* (activated) mRNA Slicer RNase
2 siRNA: small interfering RNA RISC: RNAi silencing complex RISC*: activated RISC Slicer: it cleaves mRNA RNase: ribonuclease RNA interference – amplification Dicer Double-stranded RNA siRNAs Dicer mRNA Amplified double- stranded RNA RNA-dependent RNA polymerase many siRNAs