A common substrate recognition mode conserved between katanin p60 and VPS4 governs microtubule severing and membrane skeleton reorganization

J Biol Chem. 2010 May 28;285(22):16822-9. doi: 10.1074/jbc.M110.108365. Epub 2010 Mar 25.

Abstract

Katanin p60 (kp60), a microtubule-severing enzyme, plays a key role in cytoskeletal reorganization during various cellular events in an ATP-dependent manner. We show that a single domain isolated from the N terminus of mouse katanin p60 (kp60-NTD) binds to tubulin. The solution structure of kp60-NTD was determined by NMR. Although their sequence similarities were as low as 20%, the structure of kp60-NTD revealed a striking similarity to those of the microtubule interacting and trafficking (MIT) domains, which adopt anti-parallel three-stranded helix bundle. In particular, the arrangement of helices 2 and 3 is well conserved between kp60-NTD and the MIT domain from Vps4, which is a homologous protein that promotes disassembly of the endosomal sorting complexes required for transport III membrane skeleton complex. Mutation studies revealed that the positively charged surface formed by helices 2 and 3 binds tubulin. This binding mode resembles the interaction between the MIT domain of Vps4 and Vps2/CHMP1a, a component of endosomal sorting complexes required for transport III. Our results show that both the molecular architecture and the binding modes are conserved between two AAA-ATPases, kp60 and Vps4. A common mechanism is evolutionarily conserved between two distinct cellular events, one that drives microtubule severing and the other involving membrane skeletal reorganization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATPases Associated with Diverse Cellular Activities
  • Adenosine Triphosphatases / chemistry*
  • Amino Acid Sequence
  • Animals
  • Cell Membrane / metabolism*
  • Endosomal Sorting Complexes Required for Transport / chemistry*
  • Endosomes / metabolism
  • Humans
  • Katanin
  • Magnetic Resonance Spectroscopy
  • Mice
  • Microtubules / metabolism*
  • Molecular Sequence Data
  • Mutation
  • Protein Structure, Tertiary
  • Sequence Homology, Amino Acid

Substances

  • Endosomal Sorting Complexes Required for Transport
  • Adenosine Triphosphatases
  • ATPases Associated with Diverse Cellular Activities
  • VPS4B protein, human
  • Vps4b protein, mouse
  • Katanin