It is almost 70 years since Mikhail Chailakhyan put forward his hormonal theory of flowering induction, which envisaged the leaves producing and exporting to the shoot apex a specific floral hormone which he called „florigen”. The search for isolation of mythical florigen ended unsuccessfully. However, the investigations have shown that fundamental for flower induction is cooperation between family of flowering gens which express high activity in cells of vascular bundles. The mobile flowering signal could be a product of one of them in the form of transcript mRNA or protein.

COP9 Sygnalosome ( CONSTITUTIVE PHOTOMORPHOGENIC 9) referred more often abbreviated as CSN ( COP9 signalosome called ) is a multiprotein complex nuclear commonly occurring Eucariotes . The results of many diverse studies have shown CSN participate in a wide range of vital processes , such as photomorhogenesis , regulation of cell cycle or cell differentiation . Increasingly complex COP9 signalosome is associated with the control of the ubiquitin mediated protein degradation .