[2][3] LOV domains are e.g. encountered in phototropins, which are blue-light-sensitive protein complexes regulating a great diversity of biological processes in higher plants as well as in micro-algae.
[4][5][6][7] [8] Phototropins are composed of two LOV domains, each containing a non-covalently bound flavin mononucleotide (FMN) chromophore in its dark-state form, and a C-terminal Ser-Thr kinase.
[11][12][13] WCC is primarily responsible for the light-induced transcription on the control-gene frequency (FRQ) under day-light conditions, which drives the expression of VVD-LOV and governs the negative feedback loop onto the circadian clock.
[12][15] LOV domains have been found to control gene expression through DNA binding and to be involved in redox-dependent regulation, like e.g. in the bacterium Rhodobacter sphaeroides.
[16][17] Notably, LOV-based optogenetic tools [18] have been gaining wide popularity in recent years to control a myriad of cellular events, including cell motility,[19] subcellular organelle distribution,[20] formation of membrane contact sites,[21] microtubule dynamics,[22] transcription,[23] and protein degradation.