The emergency of anisotropy of lysozyme molecule motion may qualitatively indicate the emergency of anisotropy of αβ-tubulin motion under corresponding solution conditions. Fas is the accommodating space factor which says how many times the accommodating space is greater than the volume of one protein molecule. Accommodating space is the space which accommodates free rotation and translation of single protein molecule. The volume of lysozyme molecule, approximated by cylinder is ~141.3 nm3 (Matthews and Remington ). The volume of αβ-tubulin molecule, approximated by cylinder is ~464.5 nm3 (Nogales, et al. ). *Anisotropy is the anisotropy of αβ-tubulin motion obtained by extrapolation from lysosyme data under corresponding solution conditions (Table three in Dlugosz and Antosiewicz ).