Human CLP 36 , a PDZ domain and LIM domain protein , binds to alpha actinin 1 and associates with actin filaments and stress fibers in activated platelets and endothelial cells . ^^^ Yeast 2 hybrid analysis demonstrated that the intervening sequence , but not the PDZ or the LIM domain of CLP 36 , binds to the spectrinlike repeats 2 and 3 of alpha actinin 1 . ^^^