Cyclins are first discovered as proteins that varied in abundance during the cell cycle (Hunt 2004). Cyclin A is one of the first members of the cyclin family to be cloned. Classical cyclins are activating subunits for cyclin-dependent kinases (CDKs) and are essential components of the cell cycle engine (Morgan 2007). Some members of the cyclin family are also known to perform functions unrelated to cell cycle control (Lim and Kaldis 2013).
Two cyclin A are present in vertebrates. Cyclin A1 is the “embryonic” form, expressing mainly in early zygotes and testis. Cyclin A2 is the “somatic” form and is widely expressed in most growing cells. In the literature, “cyclin A” generally refers to cyclin A2. Notable exceptions are papers on Xenopus embryonic cells, in which the unspecified “cyclin A” generally refers to cyclin A1.
Cyclin A is expressed periodically during the cell cycle, accumulating from early S phase and...
- Morgan DO. The cell cycle: principles of control. Oxford: Oxford University Press; 2007.Google Scholar