HDAC6 is a major cytoplasmic a-tubulin deacetylase that is involved in cell motility and adhesion. GRK2 dynamically and directly associates with and phosphorylates HDAC6 to stimulate its a-tubulin deacetylase activity at specific cellular localizations, such as the leading edge of migrating cells, thus promoting local tubulin deacetylation and enhanced motility.