The proteins of this family were originally isolated since they copurify with tubulin in polymerization experiments: tubulin in cell extracts can be made to polymerize to produce microtubules (MT) under the influence of heat and the addition of GTP, and the MT can then be collected by centrifugation.
When this is done a series of microtubule associated proteins are collected along with the MT and can be detected by SDS-PAGE and other methods.
[7] All forms of MAP2 share a common core sequence which includes MT binding domains, 18 amino acid sequences which are found in other MT associated proteins such as MAP Tau and MAP1B.
The MAP2 isoforms are thought to be involved in MT assembly, which is an essential step in neuritogenesis.
As a result antibodies to MAP2 are widely used to identify neuronal cells and trace dendritic processes in experimental contexts.