TY  - JOUR
A1  - Vieira, Jacqueline
A1  - Jones, Alex R.
A1  - Danon, Antoine
A1  - Sakuma, Michiyo
A1  - Hoang, Nathalie
A1  - Robles, David
A1  - Tait, Shirley
A1  - Heyes, Derren J.
A1  - Picot, Marie
A1  - Yoshii, Taishi
A1  - Helfrich-Förster, Charlotte
A1  - Soubigou, Guillaume
A1  - Coppee, Jean-Yves
A1  - Klarsfeld, André
A1  - Rouyer, Francois
A1  - Scrutton, Nigel S.
A1  - Ahmad, Margaret
T1  - Human Cryptochrome-1 Confers Light Independent Biological Activity in Transgenic Drosophila Correlated with Flavin Radical Stability
JF  - PLoS One
N2  - Cryptochromes are conserved flavoprotein receptors found throughout the biological kingdom with diversified roles in plant development and entrainment of the circadian clock in animals. Light perception is proposed to occur through flavin radical formation that correlates with biological activity in vivo in both plants and Drosophila. By contrast, mammalian (Type II) cryptochromes regulate the circadian clock independently of light, raising the fundamental question of whether mammalian cryptochromes have evolved entirely distinct signaling mechanisms. Here we show by developmental and transcriptome analysis that Homo sapiens cryptochrome - 1 (HsCRY1) confers biological activity in transgenic expressing Drosophila in darkness, that can in some cases be further stimulated by light. In contrast to all other cryptochromes, purified recombinant HsCRY1 protein was stably isolated in the anionic radical flavin state, containing only a small proportion of oxidized flavin which could be reduced by illumination. We conclude that animal Type I and Type II cryptochromes may both have signaling mechanisms involving formation of a flavin radical signaling state, and that light independent activity of Type II cryptochromes is a consequence of dark accumulation of this redox form in vivo rather than of a fundamental difference in signaling mechanism.
KW  - arabidopsi
KW  - dependent magnetosensitvity
KW  - protein
KW  - clock
KW  - gene
KW  - mechanism
KW  - rhythm
KW  - oscillator
KW  - circadian photoreception
KW  - mammalian CRY1
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-134513
VL  - 7
IS  - 3
ER  - 
TY  - JOUR
A1  - Schlichting, Matthias
A1  - Rieger, Dirk
A1  - Cusumano, Paola
A1  - Grebler, Rudi
A1  - Costa, Rodolfo
A1  - Mazzotta, Gabriella M.
A1  - Helfrich-Förster, Charlotte
T1  - Cryptochrome interacts with actin and enhances eye-mediated light sensitivity of the circadian clock in Drosophila melanogaster
JF  - Frontiers in Molecular Neuroscience
N2  - Cryptochromes (CRYs) are a class of flavoproteins that sense blue light. In animals, CRYs are expressed in the eyes and in the clock neurons that control sleep/wake cycles and are implied in the generation and/or entrainment of circadian rhythmicity. Moreover, CRYs are sensing magnetic fields in insects as well as in humans. Here, we show that in the fruit fly Drosophila melanogaster CRY plays a light-independent role as “assembling” protein in the rhabdomeres of the compound eyes. CRY interacts with actin and appears to increase light sensitivity of the eyes by keeping the “signalplex” of the phototransduction cascade close to the membrane. By this way, CRY also enhances light-responses of the circadian clock.
KW  - Drosophila melanogaster
KW  - cryptochrome
KW  - F-actin
KW  - phototransduction
KW  - activity rhythms
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-177086
VL  - 11
IS  - 238
ER  -