Novel ATP‐binding and autophosphorylation activity associated with <i>Arabidopsis</i> and human cryptochrome‐1

Bouly, Jean Pierre; Giovani, Baldissera; Djamei, Armin; Mueller, M.P.; Zeugner, Anke; Dudkin, Elizabeth A.; Batschauer, Alfred; Ahmad, Margaret

doi:10.1046/j.1432-1033.2003.03691.x

Cited by 92 publications

(148 citation statements)

References 38 publications

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“…The results obtained with AtCry1 and AtCry2 are shown in Figure 2. From the data we calculated that AtCry1 binds ATP with a Kd = 4.2 μM and stoichiometry of 0.9 ATP to 1.0 AtCry1 enzyme, values which are in reasonable agreement with those published previously (17,18). For AtCry2, we obtained Kd = 0.9 μM and stoichiometry of 0.6 ATP to 1.0 AtCry2.…”

Section: Atp Binding Of Cryptochromessupporting

confidence: 90%

“…A previous study found that preillumination of the protein, which reduces the flavin cofactor (19), increases the subsequent light-stimulated kinase activity of the pigment (18). Conversely, it was reported that the presence of I 2 that quenches the excited state and of H 2 O 2 that oxidizes the flavin, abolished the light stimulation of the kinase activity (18).…”

Section: Effect Of Light and The Redox Status Of Fad On The Kinase Acmentioning

confidence: 98%

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Analysis of Autophosphorylating Kinase Activities of Arabidopsis and Human Cryptochromes

Özgür

Sancar

2006

Biochemistry

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Cryptochromes are FAD-based blue-light photoreceptors that regulate growth and development in plants and the circadian clock in animals. Arabidopsis thaliana and humans possess two cryptochromes. Recently, it was found that Arabidopsis cryptochrome 1 (AtCry1) binds ATP and exhibits autokinase activity that is simulated by blue light. Similarly, it was reported that human cryptochrome 1 (HsCry1) exhibited autophosphorylation activity under blue light. To test the generality of light stimulated kinase function of cryptochromes, we purified AtCry1, AtCry2, HsCry1 and HsCry2 and probed them for kinase activity under a variety of conditions. We find that AtCry1, which contains near stoichiometric amount of FAD and human HsCry1 and HsCry2, which contain only trace amounts of FAD have autokinase activity but AtCry2, which also contains stoichiometric amounts of FAD does not. Finally, we find that the kinase activity of AtCry1 is not significantly affected by light or the redox status of the flavin cofactor.

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Section: Atp Binding Of Cryptochromessupporting

confidence: 90%

Section: Effect Of Light and The Redox Status Of Fad On The Kinase Acmentioning

confidence: 98%

Analysis of Autophosphorylating Kinase Activities of Arabidopsis and Human Cryptochromes

Özgür

Sancar

2006

Biochemistry

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“…With respect to flavin content, CRYs fall into two groups. The first group, which includes Arabidopsis CRYs and Insect CRY1s can be purified from bacterial and insect expression systems with essentially stoichiometric amounts of FAD (Lin et al 1995;Malhotra et al 1995;Bouly et al 2003;Özgür and Sancar 2006;). In contrast, the second group, which includes vertebrate CRYs and Insect CRY2s, contains 1-2% FAD and trace amounts of MTHF when purified from bacterial (Hsu et al 1996), insect (Özgür and Sancar 2006;), or mammalian (Özgür and Sancar 2003) expression systems.…”

Section: Physical Propertiesmentioning

confidence: 99%

“…It was found that both AtCRY1 and AtCRY2 are phosphorylated in vivo upon blue light exposure (Shalitin et al 2002;. Later, it was shown that purified AtCRY1 bound ATP stoichiometrically and that both AtCRY1 (Bouly et al 2003;Shalitin et al 2003) and human CRY1 (Bouly et al 2003) were autophosphorylated in a FAD-and blue-light-dependent manner. In line with these biochemical findings, the crystal structure of the AtCRY1 PHR domain contained an ATP analog in the cavity leading to FAD where the pyrimidine dimer binds in photolyase (Brautigam et al 2004).…”

Section: Protein-protein Interactionsmentioning

confidence: 99%

“…Conversely, dark incubation of CRY(FADH -) resulted in reoxidization back to the photoactive FAD ox form. Second, it was reported that blue light activated the AtCRY1 kinase (Bouly et al 2003) and that this activation was dependent on photoinduced electron transfer through the so-called "Trp triad." Mutations of one of the three tryptophans to phenylalanine blocked photoreduction and abolished light-induced kinase activity (Zeugner et al 2005).…”

Section: Functional Properties Of Animal Cryptochrome Cryptochrome Phmentioning

confidence: 99%

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Structure and Function of Animal Cryptochromes

Öztürk

Song²,

Özgür³

et al. 2007

Cold Spring Harbor Symposia on Quantitative Biology

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Cryptochrome (CRY) is a photolyase-like flavoprotein with no DNA-repair activity but with known or presumed blue-light receptor function. Animal CRYs have DNA-binding and autokinase activities, and their flavin cofactor is reduced by photoinduced electron transfer. In Drosophila, CRY is a major circadian photoreceptor, and in mammals, the two CRY proteins are core components of the molecular clock and potential circadian photoreceptors. In mammals, CRYs participate in cell cycle regulation and the cellular response to DNA damage by controlling the expression of some cell cycle genes and by directly interacting with checkpoint proteins. in response to blue light (Koornneef et al. 1980), was isolated and sequenced, it revealed high sequence homology with Escherichia coli photolyase, and hence, it was in retrospect, correctly speculated that HY4 encoded a blue light photoreceptor and not a signal transducer involved in blue light response (Ahmad and Cashmore 1993). Later, this protein was named cryptochrome 1 (Lin et al. 1995, and a second Arabidopsis protein that has high homology with CRY1 identified by genomics was named CRY2 . The role of CRY in Arabidopsis growth (CRY1) and differentiation (CRY2) was well established by 1995 (see Guo et al. 1998). However, as late as 1997, it was thought that CRY had no role in circadian photoreception in plants (Millar and Kay 1997).The first report implicating CRY in the circadian clock of any organism, plant or animal, came about from the study of DNA repair, in particular, the repair of UV damage in humans by photolyase. This issue had been controversial for nearly 25 years when Li et al. (1993) conducted an exhaustive study with a highly specific and sensitive assay, concluding that humans, like all placental mammals, lacked photolyase (Li et al. 1993). However, a 1995 release of a human expressed sequence tag (EST) list contained a "photolyase ortholog" entry (Adams et al. 1995). In light of this finding and the discovery of a photolyase in Drosophila and rattlesnake (Todo et al. 1993Kim et al. 1996) that repairs the minor UV-induced lesion, the (6-4) photoproduct, in contrast to the classic photolyase that repairs cyclobutane pyrimidine dimers (CPDs), the earlier conclusion regarding the lack of photolyase in humans needed reevaluation. This was done by Hsu et al. (1996) who, in addition to the "photolyase ortholog" in public databases, discovered a second human photolyase gene. Human cells expressing both genes and recombinant proteins encoded by both genes were tested for CPD and (6-4) photolyase activities and were found to lack both. Moreover, the proteins encoded by these genes, like most photolyases (Johnson et al. 1988) and Arabidopsis CRY (Lin et al. 1995; Malhorta et al. 1995), contained FAD (flavin-adenine dinucleotide) and a pterin cofactor. Therefore, it was concluded that these proteins were not repair enzymes but that, like Arabidopsis CRYs, they performed non-repair-related blue light functions and were named human CRY1 and 2 (Hsu et al. 1996). In humans ...

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Plant Cryptochromes: Their Genes, Biochemistry, and Physiological Roles

Batschauer¹

2005

Handbook of Photosensory Receptors

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Cryptochromes (cry) are sensory photoreceptors operating in the UV-A and bluelight region of the electromagnetic spectrum. They were first discovered in the plants Arabidopsis thaliana and Sinapis alba one decade ago, and afterwards identified not only in many other plant species but also in animals, humans, and bacteria. Therefore, cryptochromes are ubiquitous UV-A/blue light receptors of prokaryotes and eukaryotes. Cryptochromes are related in their sequence to DNA repair enzymes, the DNA photolyases, and share with them the same cofactor chromophores. In addition, cryptochromes seem to have conserved the ability of photolyases to bind DNA, although light absorption is used for different purposes, namely for catalysis (DNA repair) in the case of photolyase and for signaling in the case of cryptochromes. Since their discovery, a large quantity of data on the biological functions, the signaling mechanisms, and the biochemistry of cryptochromes has been accumulated and the reader is referred to several recent reviews on these topics (Ahmad, 1999; Cashmore et al.

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Novel ATP‐binding and autophosphorylation activity associated with Arabidopsis and human cryptochrome‐1

Cited by 92 publications

References 38 publications

Analysis of Autophosphorylating Kinase Activities of Arabidopsis and Human Cryptochromes

Analysis of Autophosphorylating Kinase Activities of Arabidopsis and Human Cryptochromes

Structure and Function of Animal Cryptochromes

Plant Cryptochromes: Their Genes, Biochemistry, and Physiological Roles

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