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

--- 7-8nm Microfilament (thin filament) structure minus G-actin monomer ATP 25nm QuickTime™ a nd a TIFF (Uncompre ssed ) decomp resso r are need ed to se e th is p icture.

plus

G-actin (42-43kD; 375 aas) (minus) Animation (plus) Changes upon hydrolysis

Intrafilament contacts QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

Video Polarity of assembly (

in vitro

assay) + G-actin, ATP Red arrow = minus end Green arrow = initial plus end Bulls-eye = contact point on surface QuickTime™ and a Video decompressor are needed to see this picture.

+ -

+ S1 Decoration -

S1 decoration reveals microfilament polarities

in situ

a. Cytoplasm (mixed polarities) b. Stress fibers (bundled mixed polarities) c. Lamellipodia (uniform polarity, points in)

The Angel of Death Mushroom Phalloidin

Amanita phalloides

Cells labeled with Phalloidin DNase I (F-actin) and (G-actin)

Actin Binding Proteins (ABPs) modulate architectures “. . . the actin cytoskeleton is a complex three-dimensional molecular jigsaw puzzle” - Tom Pollard

Profilin is involved in ATP recharge QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

profilin

Cofilin weakens subunit interactions by structural introgression QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

Alpha-actinin crosslinks microfilaments

Actin subunit Amoeboid motility uses Gelsolin Gelsolin (partial structure) in presence of Ca++ QuickTime™ and a Cinepak decompressor are needed to see this picture.

Video

F-actin motilities Composite time lapse segments QuickTime™ and a Video decompressor are needed to see this picture.

Actin dynamics at the leading edge GFP::actin in a QuickTi me™ and a YU V420 codec decompressor are needed to see thi s pi ctur e.

tissue culture cell QuickTime™ and a Cinepak decompressor are needed to see this picture.

2 time-lapse video sequences

QuickTime™ and a YUV420 codec dec ompres sor are needed to see this pic ture.

GFP-actin dynamics Video Axonal growth cones Video Microtubules are excluded from the periphery QuickTime™ and a Animation decompressor are needed to see this picture.

Cell microinjected with fluorescent tubulin to label microtubules

Treadmilling within the lamellipodium QuickTime™ and a Video decompressor are needed to see this picture.

Video

Keratocyte motility Video QuickTime™ and a Sorenson Video decompressor are needed to see this picture.

Arp2/3 immunolocalization QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

Branching out on the family tree: the Arp2/3 complex Coronin Nucleation Promoting Factors (NPFs) WASp/SCAR/Wave 70 o minus Quic kTime™ and a TIFF (Uncompress ed) dec ompres sor are needed to s ee this pic ture.

plus

The Actin Family Tree

+ Formin those long filaments G-actin monomer

Assembly Cycles WASp SCAR translation PIP 2 WASp VASp ATP Formin CCT Profilin Thymosin G-actin ATP ADP (exchange) ATP Arp2/3 Dynamic F- actin ADP microfilament VASp Stabilizing ABPs G-actin ADP Severin Gelsolin Stable F-actin microfilament

F-actin And VASp NPF: VASp (vasodilator stimulated phosphoprotein) QuickTime™ and a Video decompressor are needed to see this picture.

Video

G-proteins Cdc42 Signal transduction links WASp WASp*P Arp2/3 Filipodia Localized Initiation Rac PIPkinase PIP Lamellipodia Frontal Initiation PIP 2 Increased Turnover Rho MLCK Myosin Stress fibers Form and Tension Formin

Stress fibers distribute forces QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

Arrows highlight microtubules adjacent to the stress fiber bundle

Getting in shape

Neutrophil motility Video

Microvilli

Anchored in the terminal web QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.

QuickTi me™ and a TIFF (U ncompressed) decompressor are needed to see this picture.

MyoVIIa is involved in Ca++ regulated adaptation QuickTi me™ and a T IFF (Uncom pressed) decom pressor are needed to see t his pict ure.

QuickTime™ and a GIF decompressor are needed to see this picture.

Stereocilia

Act’in Up Video QuickTime™ and a Cinepak decompressor are needed to see this picture.

Listeria monocytogenes

moving in PtK2 cells