Purification and Characterization of the Danaus Plexippus Cryptochromes
Abstract
Cryptochromes are flavoproteins that function as blue-light photoreceptors to regulate growth in plants and to entrain the circadian clock in animals. The photochemical and signaling mechanisms by which cryptochromes function are still undefined. Two cryptochromes identified in Danaus plexippus have shown distinct in vivo activities where DpCryl is similar to Drosophila melanogaster cryptochrome and DpCry2 is similar to mammalian cryptochromes. I purified and biochemically characterized both D. plexippus cryptochromes. DpCryl is the first animal cryptochrome to contain near-stoichiometric flavin. Photoreduction of FADox to FAD and fluorescence lifetime measurements showing an extremely short lifetime of flavin in DpCryl both suggest a novel photochemical mechanism for DpCryl. DpCry2 contained only trace amounts of flavin and both proteins contained sub-stoichiometric MTHF. Purification of DpCryl as the first animal cryptochrome with near-stoichiometric flavin will enable crucial in vitro biochemical and biophysical experiments that have never been conducted on an animal cryptochrome.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2006
- Accession Number
- ADA462912
Entities
People
- Tracy R. Denaro
Organizations
- University of North Carolina at Chapel Hill