trimeric G-proteins, but there is a large family of GAPs for the Rho-family
GTPases. Without active nucleation-promoting factors creation of new
filaments stops rapidly, since the Arp2/3 complex activated previously is
consumed by branching nucleation. Networks in unstimulated parts of cells
are predicted to disassemble in tens of seconds, perhaps hurried along by
active ADF/cofilin relieved of inhibition by the PAK/LIM kinase pathway.
This work was supported by NIH Research Grant GM26338. The author
thanks the members of this laboratory who contributed to this work.
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