Premium
Flavin Adenine Dinucleotide and N 5 ,N 10 ‐Methenyltetrahydrofolate are the in planta Cofactors of Arabidopsis thaliana Cryptochrome 3
Author(s) -
Göbel Tanja,
Reisbacher Stefan,
Batschauer Alfred,
Pokorny Richard
Publication year - 2016
Publication title -
photochemistry and photobiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.818
H-Index - 131
eISSN - 1751-1097
pISSN - 0031-8655
DOI - 10.1111/php.12622
Subject(s) - cofactor , arabidopsis thaliana , flavin adenine dinucleotide , cryptochrome , photolyase , chemistry , flavin group , flavoprotein , arabidopsis , physics , enzyme , biochemistry , dna , gene , circadian clock , mutant , dna repair
Abstract Members of the cryptochrome/photolyase family ( CPF ) of proteins utilize noncovalently bound light‐absorbing cofactors for their biological function. Usually, the identity of these cofactors is determined after expression in heterologous systems leaving the question unanswered whether these cofactors are identical to the indigenous ones. Here, cryptochrome 3 from Arabidopsis thaliana was expressed as a fusion with the green fluorescent protein in Arabidopsis plants. Besides the confirmation of the earlier report of its localization in chloroplasts, our data indicate that fractions of the fusion protein are present in the stroma and associated with thylakoids, respectively. Furthermore, it is shown that the fusion protein expressed in planta contains the same cofactors as the His 6 ‐tagged protein expressed in Escherichia coli , that is , flavin adenine dinucleotide and N 5 ,N 10 ‐methenyltetrahydrofolate. This demonstrates that the heterologously expressed cryptochrome 3, characterized in a number of previous studies, is a valid surrogate of the corresponding protein expressed in plants. To our knowledge, this is also a first conclusive analysis of cofactors bound to an Arabidopsis protein belonging to the CPF and purified from plant tissue.