Twinfilins, which are actin monomer-binding proteins that are composed of two ADF-H domains
Abp1/Drebrins, which are relatively large proteins composed of an N-terminal ADF-H domain followed by a variable region and a C-terminal SH3 domain. Abp1/Drebrins interact only with actin filaments and do not promote filament depolymerisation or fragmentation. Although these proteins are biochemically distinct and play different roles in actin dynamics, they all appear to use the ADF-H domain for their interactions with actin.
The ADF-H domain consists of a six-stranded mixed beta-sheet in which the four central strands (beta2-beta5) are anti-parallel and the two edge strands (beta1 and beta6) run parallel with the neighbouring strands. The sheet is surrounded by two alpha-helices on each side .[1][2][4]
^Liu L, Wei Z, Wang Y, Wan M, Cheng Z, Gong W (November 2004). "Crystal structure of human coactosin-like protein". J. Mol. Biol. 344 (2): 317–23. doi:10.1016/j.jmb.2004.09.036. PMID15522287.