[The comparative analysis of subcellular fractionation methods for revealing of alpha-actinin 1 and alpha-actinin 4 in A431 cells].

Alpha-actinin 1 and alpha-actinin 4 belong to a family of actin-binding proteins with shared structural function and regulation of several processes in a cell. Based on previous data on different distribution of these proteins in the nucleus and cytoplasm, we have explored in detail the distribution of alpha-actinin 1 and alpha-actinin 4 in subcellular fractions in A431 cells spread on fibronectin. Several methods of subcellular fractionation were used. Complex approach allowed resuming that revealing of alpha-actinin isoforms in fractions depended on the composition of lysis buffer and preliminary low-temperature freezing of the cells. We have drawn a conclusion that alpha-actinin 4 can be found in all cytoplasmic and nuclear subfractions, while alpha-actinin 1 is characterized by cytoplasmic and membrane localization with specificity of its distribution tightly to the nuclear membrane.