Maternal Inheritance and Maternal Effects

Structure of Organelle Genomes

• Organelles are by-products of the events following endosymbiosis
  
• Have all the basic functions of the Central Dogma of Molecular Genetics
  
• Contain a full set of rRNA and tRNA genes
  
• Mammalian Mtochondria contains genes for:
  • Cytochrome Oxidase Subunits I, II, III
  • Cytochrome B Apoprotein
  • ATPase subunit VI
  • 6 ORFs (open reading frames)
    
• Exhibit Gene Expression Cooperation with Nuclear Genes
  • In mammals:
    • Mitochondrial Genome Encodes Cytochrome Oxidase Subunits I-III
    • Nuclear Genome Encodes Cytochrome Oxidase Subunits IV-VII
  • In plants:
    • Chloroplast Genome Encodes rbcL (large subunit of RUBISCO)
    • Nuclear Genome Encodes rbcS (small subunit of RUBISCO)|
      
• During Evolution Gene Flow Occurs Between the Organelles and the Nucleus in the Following Manner