Quiz 3 (ch 35 IFs) current topics of cell bio.txt

  1. IF role
    • 1. cell and tissue integrity
    • NO known roll in motility
    • 2. IF evolved after divergence of animals from plants
  2. IF proteins characteristics
    • 6 classes
    • 1. have similar structure but different amino acid sequences
    • 2. have diff N and c terminal domains
    • 3. have distinct gene expression patterns
  3. Keratin
    acid and basic classes
  4. Structural IF/protein characteristics
    • alpha helices wrap around to form coils
    • VERY STABLE in vivo, hard to study b/c no way of disrupting w/out killing cell
    • NO ATP/GTP required
    • Apolar assembly (Can reassemble after disassembly)
  5. Keratin and genetics (1st genetic experiment)
    • Poison protein mutation: mutant proteins actually caused greater damage than just the knockout affect
    • More C terminus deleted: the MORE IF damage
    • Blistering phenotype observed in mice with keratin mutants
    • Link to EBS: genetic skin disorder
  6. IF proteins and diseases
    • 1. Keratin (epithelial): blistering diseases
    • 2. Desmin (muscle): Myopathies
    • 3. Vimentin (mesenchymal): None...mouse still viable
    • 4. Neurofilaments (nerves): None...associated w/ALS
    • 5. Lamins (nuclear envelope): Muscular dystrophy, Progeria..rapid aging
  7. IF associated proteins
    • 1. Plectin: rod shaped, connecting other IFs together, actin and MTs
    • 2. Filaggrin: Aggregates keratin on skin surface
    • 3. BPAG1: connects Keratin to BPAG2
  8. Nuclear lamin role
    • nuclear stability and integrity
    • Also role in gene expression: progeria
Card Set
Quiz 3 (ch 35 IFs) current topics of cell bio.txt