Cytoskeleton

profilin

ensures supply of ATP G-actin, binds G-actin opposite to nucleotide binding cleft

cofilin

enhances net disassembly of filament, binds to F-actin-ADP (-) end, destabilizes F-actin filament and generates more (-) ends

thymosin-β

sequesters G-actin, inhibits addition of G-actin to either end of F-actin

CapZ

caps (+) end, prevents growth

tropomodulin

caps (-) end, prevents breaking off

formin

nucleates linear assemblies, binds to (+) end of two actins, binds profilin

Arp 2/3

nucleates branched networks, activated by interacting with NPF

myosin

moves toward (+) end of actin

myosin 1

membrane association and endocytosis

myosin 2

contraction

myosin 5

binds to vexicles and organeele transport

nebulin

binds along and determines length of thin filament

titin

holds thick filament in middle of sarcomere

tropomyosin

wraps around actin

troponin

binds to tropomyosin

rho proteins

G protein family, active in cytosol, complexed to GDI, binds effector proteins

centrosome

pair of orthogonally arranged cylindrical centrioles, 9 sets of triplets

γ-TURC

nucleates microtubules

GTP-αβ-tubulin

straight, enables lateral interactions between protofilaments

GDP-αβ-tubulin

curved, imposes structural strain

Tau protein

family of stabilizing side binding microtubule associated proteins, contain basic and acidic domains

XMAP215

increases local αβ-tubulin concentration, enhances (+) end assembly

CLASP

binds to growing end, suppresses (+) end catastrophe

kinesin 13

binds to and curves ends of protofilaments, removes tubulin dimers

kinesin 1

dimer of 2 heavy chains and 2 light chains, moves in (+) direction

kinesin 5

4 heavy chains, bipolar motors, moves in (+) direction

dynein

large dimer w/ 6AAA ATPase repeats, moves in (-) direction

dynactin domain 1

short actin/Arp1 filament capped by Cap Z, binds cargo

dynactin domain 2

p150 contains dynein-binding site and microtubule binding site

dynamitin

holds two domains together

cilia and flagella

long doublet bridged by dynein motors

nexin

links 9 doublets together

intermediate filaments

structural role and stabilize nucleus position