Aurora kinases are serine/threonine kinases that are essential for cell proliferation

Cell growth

The term cell growth is used in the contexts of cell development and cell division . When used in the context of cell division, it refers to growth of cell populations, where one cell grows and divides to produce two "daughter cells"...

. The enzyme

Enzyme

Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...

 helps the dividing cell dispense its genetic materials

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

 to its daughter cells. More specifically, Aurora kinases play a crucial role in cellular division by controlling chromatid

Chromatid

A chromatid is one of the two identical copies of DNA making up a duplicated chromosome, which are joined at their centromeres, for the process of cell division . They are called sister chromatids so long as they are joined by the centromeres...

 segregation. Defects in this segregation can cause genetic instability, a condition which is highly associated with tumorigenesis.

Three Aurora kinases have been identified in mammalian cells to date. Besides being implicated as mitotic regulators, these three kinases have generated significant interest in the cancer research field due to their elevated expression profiles in many human cancers. The human Aurora kinases present a similar domain organization, with a N-terminal domain of 39 to 129 residues in length, a protein kinase domain and a short C-terminal domain containing 15 to 20 residues. The N-terminal domain of three proteins share low sequence conservation, which determines selectivity during protein-protein interactions (Bolanos-Garcia, 2005).

Classes

As, mentioned above, there are three classes of aurora kinases:

• Aurora A
  Aurora A kinase
  Aurora A kinase also known as serine/threonine-protein kinase 6 is an enzyme that in humans is encoded by the AURKA gene.Aurora A is a member of a family of mitotic serine/threonine kinases. It is implicated with important processes during mitosis and meiosis whose proper function is integral for...
  
   (aka Aurora 2) functions during prophase
  Prophase
  Prophase, from the ancient Greek πρό and φάσις , is a stage of mitosis in which the chromatin condenses into a highly ordered structure called a chromosome in which the chromatin becomes visible. This process, called chromatin condensation, is mediated by the condensin complex...
  
   of mitosis
  Mitosis
  Mitosis is the process by which a eukaryotic cell separates the chromosomes in its cell nucleus into two identical sets, in two separate nuclei. It is generally followed immediately by cytokinesis, which divides the nuclei, cytoplasm, organelles and cell membrane into two cells containing roughly...
  
   and is required for correct function of the centrosome
  Centrosome
  In cell biology, the centrosome is an organelle that serves as the main microtubule organizing center of the animal cell as well as a regulator of cell-cycle progression. It was discovered by Edouard Van Beneden in 1883...
  
  s (the microtubule organising centres in eukaryotic cells).

• Aurora B
  Aurora B kinase
  Aurora B kinase is a protein that functions in the attachment of the mitotic spindle to the centromere.In cancerous cells, over-expression of these enzymes causes unequal distribution of genetic information, creating aneuploid cells, a hallmark of cancer....
  
   (aka Aurora 1) functions in the attachment of the mitotic spindle to the centromere.

• Aurora C works in germ-line cells and little is known about its function.