Organizing the cell: the Cytoskeleton

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Organizing the cell the Cytoskeleton
Intermediate Filaments
Microfilaments
Microtubules
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Microtubules
Text and image sources are included using the
notes function of this file
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EM views
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FtsZ a prokaryotic ur-tubulin?
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The Tubulin Superfamily
alpha Part of heterodimer All Eukaryotes
beta Part of heterodimer All Eukaryotes
gamma Part of microtubule initiation complex All Eukaryotes
delta Centriolar component (c-tubule) Various
epsilon Localized to centriole in a cell-cycle specific manner Various
eta Basal body component Paramecium
zeta Basal body component Trypanosomes
FtsZ Component of filaments Prokaryotes
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Microtubule model
exchangeable
GDP
GTP
Minus end
Plus end
GTP
GTP
GTP
GTP
GDP
GTP
GTP
GTP
GDP
GTP
GDP
GDP
GDP
GDP
GDP
GTP
GTP
GTP
GTP
GTP
GTP
GTP
GDP
GTP
GTP Beta-tubulin cap
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Tubulin dimer atomic structure
Plus Minus
In Out
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Microtubule fly-by
Narrated Video
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Microtubule initiation
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MTOCs
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The Centrosomerevealed
9-triplet microtubule centrioles pericentriolar
material singlet microtubules
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Washout of nocodazole
10 um
Successive images at 2 minute intervals after
changing to drug-free media (at timepoint A)
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Dynamic Instability in vitro
Video
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Dynamic instability in vivo
Video
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Fluorescence Speckle Microscopy
Video
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Disassembly
Stathmin microtubule-binding domain
Video
In vitro assembly on axonemal microtubule
seeds /- Stathmin Activity
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Katanin
Video
Microtubule wall
(Mitotic Extract) (Interphase Extract)
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Centrosomal release
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Treadmilling
Speckles
Photobleaching
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MAPs
Note the cross-bridges (arrows) between
microtubules
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Plus end tracking proteins (TIPS)
Video
Video
GFPEB1 Cy3 Tubulin
um
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Interrelationship between microtubules and
microfilaments
Microtubule effects
Microfilament effects
Video
Video
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Pathways
Synthesis and Folding
Signal transduction
Integration with actin networks
cof B cof E cof C CCT cof D cof A
stathmin PAK Rac
Cdc42
a b
Rho
IQGAP
abGTP

• Tub
• CLIP-170, EB-1

mDia
GEF?
Dynamic Polymer
Rho
stabilizing MAPs end capture
stathmin catastrophic kinesins
abGDP
katanin severin (EF1a)
StablePolymer
Assembly/Disassembly