Structural changes within the bifunctional cryptochrome/photolyase CraCRY upon blue light excitation.
Sci Rep
; 9(1): 9896, 2019 07 09.
Article
em En
| MEDLINE
| ID: mdl-31289290
ABSTRACT
Cryptochromes (CRYs) are an ubiquitously occurring class of photoreceptors, which are important for regulating the circadian rhythm of animals via a time-delayed transcription-translation feedback loop (TTFL). Due to their protein architecture and common FAD chromophore, they belong to the same superfamily as photolyases (PHLs), an enzyme class that repairs UV-induced DNA lesions upon blue light absorption. Apart from their different functions the only prominent structural difference between CRY and PHL is the highly variable C-terminal extension (CTE) of the former. The nature of the CTE is still unclear and highly speculated. In this study, we show by hydrogen/deuterium exchange and subsequent mass-spectrometric analysis that the CTE of the animal-like cryptochrome from the green algae Chlamydomonas reinhardtii (CraCRY) binds to the surface of the photolyase homology region, which flanks the DNA binding site. We also compared the fully oxidized and fully reduced states of the flavoprotein and designed a tool, so called light chamber, for automated HDX-MS measurements of photoreceptors in defined photostates. We could observe some striking differences between the two photostates and propose a model for light-dependent switching of this bifunctional cryptochrome.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Chlamydomonas reinhardtii
/
Criptocromos
/
Luz
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article