Aurora Kinase

Aurora kinases are of particular relevance as they play a crucial role in cellular division by controlling chromatids segregation. Mammalian genomes uniquely encode for three Aurora kinases, Aurora A, Aurora B, and Aurora C, while for other metazoans, including the frog, fruitfly and nematode, only Aurora A and B kinases are known. Human Auroras A–C are kinases of a size ranging from 309 to 403 amino acid residues that exhibit a relatively high sequence divergence between species. The maintenance of a functional balance between mitotic checkpoint proteins and Aurora A is essential for the proper progression through mitosis. Moreover, this kinase is a key regulatory component of the p53 pathway as its overexpression leads to increased p53 degradation, which facilitates oncogenic transformation. Aurora B also plays an essential role in chromosome segregation and cytokinesis and its kinase activity is required for bipolar chromosome orientation and condensation. Aurora C is expressed at a moderate level albeit about an order of magnitude lower than Aurora B in diploid human fibroblasts. In contrast, the level of Aurora C is elevated in several human cancer cell types. Auroras C and B protein expression is maximally elevated during the G2/M phase but their expression profiles in synchronized cells reveal differential temporal regulation through the cell cycle.

References

1.Bolanos-Garcia VM. Int J Biochem Cell Biol. 2005 Aug;37(8):1572-7.