A family of highly conserved protein kinases known as Aurora is important in many aspects of cell division. Mammals contain three Aurora kinases: Aurora A, B, and C, but yeasts only have one. The cytoskeleton and chromosomes, as well as their interactions at the kinetochore, are regulated by Aurora kinases during mitosis. Additionally, they control cytokinesis and the spindle-assembly checkpoint pathways signaling. Cancer may develop if Aurora kinase expression or function are altered.
Important things to note
During cell division, the conserved serine/threonine kinases of the Aurora family play crucial roles. Despite having extremely similar sequences, the three mammalian paralogues have highly different localizations, functions, substrates, and regulatory partners.
During mitosis, Aurora A is mostly found near the spindle poles, where it is necessary for centrosome development and separation. Spindle assembly necessitates that Aurora A be targeted to spindle pole microtubules by the targeting protein for XKLP 2 (TPX2) via a process requiring Ran-GTP. Additionally, Aurora A plays a role in meiosis by assisting with oocyte maturation, polar-body extrusion, spindle orientation, and metaphase I departure.
Through phosphorylation/dephosphorylation and degradation, Aurora A is controlled. Protein phosphatase 1 inhibits Aurora, while TPX2 controls this connection. In late mitosis, Aurora is targeted for destruction by an anaphase-promoting complex/cyclosome (APC/C) that is connected to Cdh1/Fizzy.
Chromosome-passenger protein Aurora B serves a variety of purposes during mitosis. Two other elements of the passenger complex, the inner centromere protein (INCENP) and survivin, serve as the kinase’s regulatory and targeting elements. Condensin targeting, histone 3 phosphorylation, and typical chromosomal compaction all depend on Aurora B. The checkpoint for spindle assembly as well as kinetochore-microtubule contacts and chromosomal biorentation have all recently been demonstrated to depend on it.
For cytokinesis to be completed, Aurora B is necessary. Its cleavage furrow substrates include the myosin II regulatory chain, vimentin, desmin, and glial fibrillary acidic protein. MgcRacGAP is phosphorylated by Aurora B, which causes it to become an activator of RhoA in the contractile ring.
There is not much information available on Aurora-C kinases; they are not covered in length here, save from the fact that they appear to be expressed preferentially in meiotic cells.
The misexpression of Aurora kinases has been associated with cancer, although their potential contribution to carcinogenesis has not yet been fully understood.
In the course of the cell cycle, INCENP, survivin, and TPX2—their binding partner-substrates—help Aurora kinases reach to their subcellular destinations. This adds an extra layer of control that may be necessary for the orchestration of mitotic events.
Helpful Hints: You can peruse the Chemdiv Compound Collection’s collection of possibly selective Aurora A kinase inhibitors here if that is your theory. Around 10,000 distinct compounds may be found in the aurora libraries.