Table 1.
Protein | Domain type | Affinity to F-actin (K d) | Interaction site | Function (in vitro)a | Function (in vivo)a |
---|---|---|---|---|---|
PICK1 | N-BAR |
0.3 µM [105]b 2.0–3.0 μM [78]c |
BAR domain K251, K252 [105] |
1. Inhibits Arp2/3-mediated actin nucleation [105]d 2. Binds to F-actin, but it neither binds nor inhibits Arp2/3 complex [78] |
1. Contribution to specific form of vesicle trafficking, and the development of neuronal architecture [105] 2. No colocalization and binding with actin in vivo [78] |
Gas7 | F-BAR | 0.3 µM [104]e | BAR domain [104]f | Promotes actin assembly and crosslinks actin filaments [104] | Reorganization of microfilaments and promoting of membrane outgrowth [104] |
PSTPIP2 | F-BAR | N.D | BAR domain [106]f, g | Induces actin bundling, reduces the rate of actin polymerization, and increases its stability [106] | Effects on actin bundling and filopodia formation, and directional migration [106] |
Pacsin-2 | F-BAR | 2.0 μM [50] | BAR domain mainly two clusters of lysine residues [50]h | Increases the stability of F-actin [50] | N.D |
MIM | I-BAR | 17 µM [107] | BAR domain basic residues at the distal ends of the dimer [8] i |
1. Filopodia/microspike formation [99, 111] 2. Does not contribute to filopodia formation [8] |
|
IRSp53 | I-BAR | 5 µM [6] | BAR domain basic residues at the distal ends of the dimer [6]i | Bundling of actin filaments [6, 111] | Filopodia formation [6] |
N.D. not determined
aFunction related to F-actin binding
bKd determined for the full length protein; isolated BAR domain bound to actin more efficiently than full length PICK1
cKd determined for the full length protein
dThrough interactions of the BAR domain with F-actin and the ACT with Arp2/3
eDetermined indirectly by comparison with α-catenin
fDetailed mapping was not done
gExperiments were done with the full length protein, which does not have any other domain than BAR
hIndentified by cross-linking; however, some other residues might be involved as well
iOther parts of the I-BAR are most likely also involved