A novel photoreaction mechanism for the circadian blue light photoreceptor Drosophila cryptochrome

Alex Berndt, Tilman Kottke, Helena Breitkreuz, Radovan Dvorsky, Sven Hennig, Michael Alexander, Eva Wolf

Research output: Contribution to JournalArticleAcademicpeer-review

Abstract

Cryptochromes are flavoproteins that are evolutionary related to the DNA photolyases but lack DNA repair activity. Drosophila cryptochrome (dCRY) is a blue light photoreceptor that is involved in the synchronization of the circadian clock with the environmental light-dark cycle. Until now, spectroscopic and structural studies on this and other animal cryptochromes have largely been hampered by difficulties in their recombinant expression. We have therefore established an expression and purification scheme that enables us to purify mg amounts of monomeric dCRY from Sf21 insect cell cultures. Using UV-visible spectroscopy, mass spectrometry, and reversed phase high pressure liquid chromatography, we show that insect cell-purified dCRY contains flavin adenine dinucleotide in its oxidized state (FAD(ox)) and residual amounts of methenyltetrahydrofolate. Upon blue light irradiation, dCRY undergoes a reversible absorption change, which is assigned to the conversion of FAD(ox) to the red anionic FAD(.) radical. Our findings lead us to propose a novel photoreaction mechanism for dCRY, in which FAD(ox) corresponds to the ground state, whereas the FAD(.) radical represents the light-activated state that mediates resetting of the Drosophila circadian clock.

Original languageEnglish
Pages (from-to)13011-21
Number of pages11
JournalJournal of Biological Chemistry
Volume282
Issue number17
DOIs
Publication statusPublished - 27 Apr 2007

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Cryptochromes
Flavin-Adenine Dinucleotide
Drosophila
Light
Circadian Clocks
Insects
Clocks
Deoxyribodipyrimidine Photo-Lyase
High pressure liquid chromatography
Sf9 Cells
Flavoproteins
Photoperiod
Reverse-Phase Chromatography
Cell culture
DNA Repair
Ground state
Purification
Mass spectrometry
Mass Spectrometry
Spectrum Analysis

Keywords

  • Animals
  • Cell Line
  • Circadian Rhythm
  • Cryptochromes
  • DNA Repair
  • Deoxyribodipyrimidine Photo-Lyase
  • Drosophila
  • Drosophila Proteins
  • Flavin-Adenine Dinucleotide
  • Flavoproteins
  • Oxidation-Reduction
  • Photochemistry
  • Photoreceptor Cells, Invertebrate
  • Journal Article
  • Research Support, Non-U.S. Gov't

Cite this

Berndt, Alex ; Kottke, Tilman ; Breitkreuz, Helena ; Dvorsky, Radovan ; Hennig, Sven ; Alexander, Michael ; Wolf, Eva. / A novel photoreaction mechanism for the circadian blue light photoreceptor Drosophila cryptochrome. In: Journal of Biological Chemistry. 2007 ; Vol. 282, No. 17. pp. 13011-21.
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abstract = "Cryptochromes are flavoproteins that are evolutionary related to the DNA photolyases but lack DNA repair activity. Drosophila cryptochrome (dCRY) is a blue light photoreceptor that is involved in the synchronization of the circadian clock with the environmental light-dark cycle. Until now, spectroscopic and structural studies on this and other animal cryptochromes have largely been hampered by difficulties in their recombinant expression. We have therefore established an expression and purification scheme that enables us to purify mg amounts of monomeric dCRY from Sf21 insect cell cultures. Using UV-visible spectroscopy, mass spectrometry, and reversed phase high pressure liquid chromatography, we show that insect cell-purified dCRY contains flavin adenine dinucleotide in its oxidized state (FAD(ox)) and residual amounts of methenyltetrahydrofolate. Upon blue light irradiation, dCRY undergoes a reversible absorption change, which is assigned to the conversion of FAD(ox) to the red anionic FAD(.) radical. Our findings lead us to propose a novel photoreaction mechanism for dCRY, in which FAD(ox) corresponds to the ground state, whereas the FAD(.) radical represents the light-activated state that mediates resetting of the Drosophila circadian clock.",
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A novel photoreaction mechanism for the circadian blue light photoreceptor Drosophila cryptochrome. / Berndt, Alex; Kottke, Tilman; Breitkreuz, Helena; Dvorsky, Radovan; Hennig, Sven; Alexander, Michael; Wolf, Eva.

In: Journal of Biological Chemistry, Vol. 282, No. 17, 27.04.2007, p. 13011-21.

Research output: Contribution to JournalArticleAcademicpeer-review

TY - JOUR

T1 - A novel photoreaction mechanism for the circadian blue light photoreceptor Drosophila cryptochrome

AU - Berndt, Alex

AU - Kottke, Tilman

AU - Breitkreuz, Helena

AU - Dvorsky, Radovan

AU - Hennig, Sven

AU - Alexander, Michael

AU - Wolf, Eva

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N2 - Cryptochromes are flavoproteins that are evolutionary related to the DNA photolyases but lack DNA repair activity. Drosophila cryptochrome (dCRY) is a blue light photoreceptor that is involved in the synchronization of the circadian clock with the environmental light-dark cycle. Until now, spectroscopic and structural studies on this and other animal cryptochromes have largely been hampered by difficulties in their recombinant expression. We have therefore established an expression and purification scheme that enables us to purify mg amounts of monomeric dCRY from Sf21 insect cell cultures. Using UV-visible spectroscopy, mass spectrometry, and reversed phase high pressure liquid chromatography, we show that insect cell-purified dCRY contains flavin adenine dinucleotide in its oxidized state (FAD(ox)) and residual amounts of methenyltetrahydrofolate. Upon blue light irradiation, dCRY undergoes a reversible absorption change, which is assigned to the conversion of FAD(ox) to the red anionic FAD(.) radical. Our findings lead us to propose a novel photoreaction mechanism for dCRY, in which FAD(ox) corresponds to the ground state, whereas the FAD(.) radical represents the light-activated state that mediates resetting of the Drosophila circadian clock.

AB - Cryptochromes are flavoproteins that are evolutionary related to the DNA photolyases but lack DNA repair activity. Drosophila cryptochrome (dCRY) is a blue light photoreceptor that is involved in the synchronization of the circadian clock with the environmental light-dark cycle. Until now, spectroscopic and structural studies on this and other animal cryptochromes have largely been hampered by difficulties in their recombinant expression. We have therefore established an expression and purification scheme that enables us to purify mg amounts of monomeric dCRY from Sf21 insect cell cultures. Using UV-visible spectroscopy, mass spectrometry, and reversed phase high pressure liquid chromatography, we show that insect cell-purified dCRY contains flavin adenine dinucleotide in its oxidized state (FAD(ox)) and residual amounts of methenyltetrahydrofolate. Upon blue light irradiation, dCRY undergoes a reversible absorption change, which is assigned to the conversion of FAD(ox) to the red anionic FAD(.) radical. Our findings lead us to propose a novel photoreaction mechanism for dCRY, in which FAD(ox) corresponds to the ground state, whereas the FAD(.) radical represents the light-activated state that mediates resetting of the Drosophila circadian clock.

KW - Animals

KW - Cell Line

KW - Circadian Rhythm

KW - Cryptochromes

KW - DNA Repair

KW - Deoxyribodipyrimidine Photo-Lyase

KW - Drosophila

KW - Drosophila Proteins

KW - Flavin-Adenine Dinucleotide

KW - Flavoproteins

KW - Oxidation-Reduction

KW - Photochemistry

KW - Photoreceptor Cells, Invertebrate

KW - Journal Article

KW - Research Support, Non-U.S. Gov't

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DO - 10.1074/jbc.M608872200

M3 - Article

VL - 282

SP - 13011

EP - 13021

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

SN - 0021-9258

IS - 17

ER -