Regulating gene expression

• Gene Expression


  The process by which information from a gene is used to create a functional protein
• Transcriptional Control

  Regulation of gene expression at the transcription level
• Post-Transcriptional Control

  Regulation of gene expression after transcription
• Translational Control

  Regulation of gene expression at the translation level
• Post-Translational Control


  Regulation of gene expression after translation
• Cellular Control


  Mechanisms that control gene expression at the transcriptional, post-transcriptional, and post-translational levels
• lac Operon


  A group of genes involved in lactose metabolism in E.coli
• Transcription Factors


  Proteins that bind to DNA and regulate transcription
• mRNA


  The RNA molecule that carries genetic information from DNA to the ribosome for protein synthesis
• Chromatin Remodeling


  The process of altering chromatin structure to regulate gene expression
• Histone Modification


  Chemical modifications of histone proteins that affect DNA packing and gene transcription
• Acetylation


  The addition of acetyl groups to histones, reducing DNA packing and promoting gene transcription
• Phosphorylation

  The addition of phosphate groups to histones, reducing DNA packing and promoting gene transcription
• Methylation

  The addition of methyl groups to histones, increasing DNA packing and inhibiting gene transcription
• DNA Methylation

  The addition of methyl groups to DNA, which can inhibit gene expression
• Epigenetics


  The study of heritable changes in gene expression that do not involve changes to the underlying DNA sequence
• Activators


  Transcription factors that increase transcription rate
• Repressors


  Transcription factors that decrease transcription rate
• Euchromatin


  Loosely packed DNA accessible for transcription
• Heterochromatin


  Tightly packed DNA inaccessible for transcription
• Operon


  A cluster of genes transcribed together in prokaryotes
• Promoter


  A DNA sequence located before a gene that RNA polymerase binds to
• Operator


  A DNA sequence that transcription factors bind to in an operon
• cAMP


  Cyclic adenosine monophosphate, a secondary messenger that regulates gene expression
• CRP

  cAMP regulator protein, a protein that binds to cAMP and up-regulates gene expression