TPX2 was identified in 1997 as a 100 kDa nuclear protein. In cells TPX2, a is a microtubule nucleation factor that translocates from the nucleus - where it resides during interphase - to the mitotic spindle during mitosis.

The mitotic spindle forms when chromosomes are ready to segregate during cell division and not surprisingly this protein is also found in this specific compartment of the cell! TPX2 is required for the correct formation of the kinetochores that is crucial for the attachment of microtubules, enabling the sister chromatids to be pulled apart. Due to its function TPX2 expression is cell-cycle dependent...Read more

It's time for another HPA image of the week! This week we would like to tease an annotation that is not yet publicly available, but is coming soon in the December 4 release of the Cell Atlas.

During the cell cycle, each chromosome containing your DNA replicates. During mitosis, each chromosome lines up with its copy in the middle of the cell. At this point, the copies of each chromosome are pulled apart from each other via a structure called the mitotic spindle. In order for this chromosomal separation to happen correctly, the two copies of each chromosome must be attached to the microtubules via the kinetochore ( DeLuca J.G. et al 2002)...Read more