Microtubules have important functions ranging from maintenance of cell 
morphology to subcellular transport, cellular signaling, cell migration, and 
formation of cell polarity. At the organismal level, microtubules are crucial 
for various biological processes, such as viral entry, inflammation, immunity, 
learning and memory in mammals. Microtubules are subject to various covalent 
modifications. One such modification is tubulin acetylation, which is associated 
with stable microtubules and conserved from protists to humans. In the past 
three decades, this reversible modification has been studied extensively. In 
mammals, its level is mainly governed by opposing actions of α-tubulin 
acetyltransferase 1 (ATAT1) and histone deacetylase 6 (HDAC6). Knockout studies 
of the mouse enzymes have yielded new insights into biological functions of 
tubulin acetylation. Abnormal levels of this modification are linked to 
neurological disorders, cancer, heart diseases and other pathological 
conditions, thereby yielding important therapeutic implications. This review 
summarizes related studies and concludes that tubulin acetylation is important 
for regulating microtubule architecture and maintaining microtubule integrity. 
Together with detyrosination, glutamylation and other modifications, tubulin 
acetylation may form a unique 'language' to regulate microtubule structure and 
function.