Organizing the cell: the Cytoskeleton Microtubules Microfilaments Intermediate Filaments

MicrotubulesMicrotubules Text and image sources are included using the notes function of this file

EM views

FtsZ: a prokaryotic ur-tubulin?

The Tubulin Superfamily alphaPart of heterodimerAll Eukaryotes betaPart of heterodimerAll Eukaryotes gammaPart of microtubule initiation complex All Eukaryotes deltaCentriolar component (c-tubule) Various epsilonLocalized to centriole in a cell-cycle specific manner Various etaBasal body componentParamecium zetaBasal body componentTrypanosomes FtsZComponent of filaments Prokaryotes

Microtubule model “Minus” end “Plus” end GTP GDP GTP GDP GTP GDP GTP Beta-tubulin “cap” exchangeable

Tubulin dimer atomic structure In Out Plus Minus

Microtubule fly-by Narrated Video

Microtubule initiation

MTOCs

The Centrosome revealed 9-triplet microtubule centrioles pericentriolar material singlet microtubules

Washout of nocodazole 10 um Successive images at 2 minute intervals after changing to drug-free media (at timepoint A)

Dynamic Instability in vitro Video

Dynamic instability in vivo Video

Fluorescence Speckle Microscopy Video

Disassembly Stathmin microtubule- binding domain In vitro assembly on axonemal microtubule seeds +/- Stathmin Activity Video

Katanin Video (Mitotic Extract) (Interphase Extract) Microtubule wall

Centrosomal release

Treadmilling Speckles Photobleaching

MAPs Note the cross- bridges (arrows) between microtubules

Plus end tracking proteins (+TIPS) um GFP::EB1 Cy3 Tubulin Video

Interrelationship between microtubules and microfilaments Microtubule effects Microfilament effects Video

Pathways  cof B cof E cof C CCT cof D cof A  GTP stathmin PAK Rac  GDP Dynamic Polymer Stable Polymer GEF? Rho  Tub; CLIP-170, EB-1 stabilizing MAPs; + end capture stathmin catastrophic kinesins katanin severin (EF1  ) IQGAP mDia Cdc42 Rho Synthesis and FoldingSignal transduction Assembly/Disassembly Integration with actin networks