Table 2.
Proteins possibly involved in microtubule breakdown after Aβ insult
| Protein (gene name) | Physiological function | Pathological function | Genetic loci [12] |
|---|---|---|---|
| Tau (MAPT) | microtubule stabilization, axonal outgrowth | aberrant transport of proteins (e.g. TTLL6, fyn), f-actin dissassembly | 17q21.31 |
| TTLL6 (TTLL6) | polyGlu chain elongation, preferentially at α-tubulin | excessive polyglutamylation leading to aberrant spastin activation | 17q21.32 |
| spastin (SPAST) | microtubule dynamics, transport of membrane vesicles/endosomes, dendrite branching | microtubule breakdown | 2p22.3 |
| MARK1,2,3,4 (MARK1,2,3,4) | transport regulation via phosphorylation of MAPs | aberrant phosphorylation of MAPs resulting in decreased microtubule protection | 1:1q41 |
| 2:11q13.1 | |||
| 3:14q32.32 | |||
| 4:19q13.32 | |||
| TTLL11 (TTLL11) | polyGlu chain elongation, preferentially at α-tubulin | similar action as TTLL6 (but path. role not yet shown) | 9q33.2 |
| TTLL1 (TTLL1) | polyGlu chain initiation at α- and β- tubulin | required for action of TTLL6 and TTLL11 (but path. role not yet shown) | 22q13.2 |
| CCP1,4,5,6 (AGTPBP1, AGBL1, AGBL5, AGBL4) | remove (poly)glutamate side chains from microtubules | impaired function could result in increased polyglutamylation (but path. role not yet shown) | 1: 9q21.33 |
| 4: 15q25.3 | |||
| 5: 2p23.3 | |||
| 6: 1p33 | |||
| Katanin (KATNA1) | microtubule severing, axon branching | also activated by polyglutamylation of microtubules (but path. role not yet shown) | 6q24.3 |
| Fidgetin (FIGN) | microtubule severing, mitosis regulation | path. role not shown | 2q24.3 |