2/mitotic-specific cyclin essential for the control of the cell cycle at the G2/M (mitosis) transition. G2/M cyclins accumulate steadily during G2 and are abruptly destroyed at mitosis. Degradation is necessary for the cell to exit from mitosis. Plays a role in morphogenesis by negatively regulating polarized growth. Through binding to CDC28 regulates cytokinesis, partly by phosphorylation of the actomyosin ring component IQG1. Also involved in the phosphorylation of CDC6 and CDC54. Expressed from S phase through G2 and M phases and are degraded at the end of mitosis. Expression is down-regulated by the anti-fungal agent plagiochin E (PLE). Impairs macrophage killing during infection. Belongs to the cyclin family. Cyclin AB subfamily.