1. The structure of the kinesin-1 motor-tail complex reveals the mechanism of autoinhibition

2. Autoinhibition of kinesin-1 motor
Auto-inhibition state
active state
Tail binding to head(motor domain)
Tail binding to cargo
Release ADP
Consume ATP
No exchange of ADP
Diffuse
Walking on microtubule
Kristen J. Verhey Nature Reviews Molecular Cell Biology 10, (2009)

3. Previous research The Autoinhibiton molecular mechanism is unclear
One tail domain inhibit
acitvating dimer motor
David D.Hackey Biochemistry 48, (2009)
Tail domain
(IAK region)
Motor domain
molecular mechanism
MT binding site?
ADP binding site ?
Kinesin-1
M. F. Stock et al., J. Biol. Chem. 274, (1999).
K. A. Dietrich et al., Proc. Natl. Acad. Sci. U.S.A. 105,8938 (2008).
The Autoinhibiton molecular mechanism is unclear
→ kinesin1 and tail domain complex structure

4. kinesin-1 motor-tail complex
Material & method
Method
Get structure info from Crystal analysis
construct
Kinesin -1tail domain
The non-fusion tail peptide (NF )
975 amino acid full length
Kinesin-1 Motor domain
Kinesin N-terminal
(Drophlia Melanogaster)
ADP
Kinesin-1(KHC)

5. kinesin-1 motor-tail complex
kinesin-1 complex
motor domain(dimer)
tail domain (one)
Comparison
Blue motor domain
Cyan motor-tail complex
coiled-coil position is only major difference

6. Tail-domain interaction site
Tail domain（residues 937 to 952）
straight structure like β sheet
D185-K hydrogen bond
H136-P C-H π interaction
F135,I126-I945
F135,I126-I942
Hydrophobic bond
symmetry ?

7. the tail domain peptide fitting
Symmetry of the tail-domain site
the tail domain peptide fitting
electron-density
Center- E944

8. kinesin-1 motor-tail complex
Tail domain（residues 937 to 952）
1,No interaction with other site
2,one motor dimer have one site
3,the interaction site in motor domain
have pseudosymmetry
kinesin-1 motor domain +
Tail domain

9. double down mechanism If kinesin dimer are crosslinked in PS center
Pesudosymmetry
center
Double locked down
Single point attach
ATP
ADP
If kinesin dimer are crosslinked in PS center

10. Cross-linked kinesin Rerelease of ADP
Material and method
construct
181th
Amino acid
181Ser
181Cys
Kinesin (C-terminal His6 tag )
crosslink
SDS PAGE (check crosslink)

11. decreases by crosslinking
Cross-linked kinesin Rerelease of ADP
SH→-SH HS-
SS→-S-S-
+DTT
→-S-S-cleavage
MANT- ADP release
Release of MANT-ADP
decreases by crosslinking

12. conclusion 1,Tail interface crosslink motor domain
2,two point connection prevent
kinesin-1 from undocking the neck
3,stop ADP release