Polypeptides contain central, rod-shaped, (A)-helical domain of similar length & homologous AA sequence.Domain flanked on either side by globular domains of various sizes and sequence
(A)-helical rods of 2 polypeptides wrap around each other to form a dime
r ~45nm in length. Dimer has polarity
- Two dimers become aligned in staggered fashion w/ N- and C-terminus in antiparallel directions. Tetramer lacks polarity
- Tetramer associate w/1 another both side to side & end to end to form poorly described intermediates that assemble into final filament
IFs are less sensitive to chemical agents and more difficult to solubilize.
Assembly & disassembly of most IFs are controlled by phosphorylation of subunits