TPX2
Developmental stage
Exclusively expressed in proliferating cells from the transition G1/S until the end of cytokinesis.
Function
Spindle assembly factor required for normal assembly of mitotic spindles. Required for normal assembly of microtubules during apoptosis. Required for chromatin and/or kinetochore dependent microtubule nucleation. Mediates AURKA localization to spindle microtubules (PubMed:18663142, PubMed:19208764, PubMed:37728657). Activates AURKA by promoting its autophosphorylation at 'Thr-288' and protects this residue against dephosphorylation (PubMed:18663142, PubMed:19208764). TPX2 is inactivated upon binding to importin-alpha (PubMed:26165940). At the onset of mitosis, GOLGA2 interacts with importin-alpha, liberating TPX2 from importin-alpha, allowing TPX2 to activate AURKA kinase and stimulate local microtubule nucleation (PubMed:26165940).
Sequence Similarities
Belongs to the TPX2 family.
Tissue Specificity
Expressed in lung carcinoma cell lines but not in normal lung tissues.
Cellular localization
- Nucleus
- Cytoplasm
- Cytoskeleton
- Spindle
- Cytoplasm
- Cytoskeleton
- Spindle pole
- During mitosis it is strictly associated with the spindle pole and with the mitotic spindle, whereas during S and G2, it is diffusely distributed throughout the nucleus. Is released from the nucleus in apoptotic cells and is detected on apoptotic microtubules.
Alternative names
C20orf1, C20orf2, DIL2, HCA519, TPX2, Targeting protein for Xklp2, Differentially expressed in cancerous and non-cancerous lung cells 2, Hepatocellular carcinoma-associated antigen 519, Hepatocellular carcinoma-associated antigen 90, Protein fls353, Restricted expression proliferation-associated protein 100, DIL-2, p100