Negatively regulates axonal outgrowth and is essential for normal synaptic transmission. Not required for regulation of axon polarity. Promotes acetylation of alpha-tubulin. Interacts with alpha-tubulin. Moderately expressed in adult brain, placenta, skeletal muscle, heart, kidney, pancreas, lung, spleen and colon. Expression was weaker in adult liver, kidney, spleen, and ovary, and in fetal brain and liver. In the brain, it is expressed in the cerebral cortex; the frontal, parietal, occipital and temporal lobes; the paracentral gyrus; the pons; the corpus callosum and the hippocampus. Highest expression levels in the brain were found in the cerebral cortex and the frontal and parietal lobes. Belongs to the DIP2 family. Contaminating sequence. Contaminating sequence. Truncated N-terminus.