Flavin Binding Domain Proteins As Photoreceptors In Photosynthetic Eukaryotes

The phototropins were the pioneer proteins for the class of proteins using LOV domains as light sensors (Christie et al, 1999 see Chapter 12). PHOT-1 and PHOT-2 mediate nontranscriptional effects of blue light and thereby direct diverse aspects of the photobiology of organisms. As we have seen above, the LOV domain of WC-1 is clearly mediates a transcriptional effect by strongly potentiating the transcriptional activating ability of the WCC. The structural means by which the LOV domain in VVD...

Wc1 And Wc2 Positive Elements In The Circadian Feedback Loop

Circadian rhythmicity is inextricably linked with light responses in most organisms even though the clock will by design continue to run in the absence of light cues, it is light and dark transitions that most commonly provide the cues required to correctly phase the internal clock oscillation so that internal subjective day as experienced in the cell corresponds to external day as defined by the earth's rotation. For this reason, although it is only indirectly associated with the photobiology...

The Discovery Of Cryptochrome

Cryptochromes, first identified in Arabidopsis Ahmad and Cashmore, 1993 , have also been found in green algae Small et al., 1995 and are now known to occur throughout the plant kingdom, including ferns Kanegae and Wada, 1998 and mosses Imaizumi et al., 2002 see Chapters 24, 25 . Cryptochromes have also been described for animals, including flies Emery et al., 1998 Stanewsky et al., 1998 and humans Hsu et al., 1996 Todo et al., 1996 where, as in plants, they play a role in circadian behaviour...

Vera Quecini And Emmanuel Liscum

2.1.1 Cryptochrome Signalling and Photomorphogenic Growth Responses Both cryl and cry2 appear to contribute to the regulation of photomorphogenetic development of Arabidopsis under monochromatic B conditions although to different extents cryl being dominant under high-intensity B and cry2 functioning mainly at low B intensities Mockler et al., 1999 Mazzella et al., 2001 . The light-sensing capacity of cryl and cry2 is mediated by the amino N -terminal PHR photolyaserelated domain , while the...