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Cleaned up text to make it more readable. Extended references. Deleted reference #1 and #2 after reading them - they review circadian rhythm entrainment via light, but do not reference cryptochrome
Actually not a gene-12-stub. Added external link.
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==External links==
==External links==
* {{MeshName|cryptochrome}}
* {{MeshName|cryptochrome}}
* website of Dr. Steven M. Reppert [http://www.umassmed.edu/neuroscience/faculty/reppert.cfm?start=0]


{{Flavoproteins}}
{{Flavoproteins}}


[[Category:Plant physiology]]
[[Category:Physiology]]
[[Category:Pigments]]
[[Category:Pigments]]
[[Category:Sensory receptors]]
[[Category:Sensory receptors]]


{{gene-12-stub}}
{{botany-stub}}


[[de:Cryptochrom]]
[[de:Cryptochrom]]

Revision as of 20:45, 24 September 2008

cryptochrome 1 (photolyase-like)
Identifiers
SymbolCRY1
Alt. symbolsPHLL1
NCBI gene1407
HGNC2384
OMIM601933
RefSeqNM_004075
UniProtQ16526
Other data
LocusChr. 12 q23-q24.1
Search for
StructuresSwiss-model
DomainsInterPro
cryptochrome 2 (photolyase-like)
Identifiers
SymbolCRY2
NCBI gene1408
HGNC2385
OMIM603732
RefSeqNM_021117
UniProtQ49AN0
Other data
LocusChr. 11 p11.2
Search for
StructuresSwiss-model
DomainsInterPro

Cryptochrome is a name used for the blue light photoreceptors of plants and animals. The word cryptochrome derives from the Greek κρυπτό χρώμα (krupto chroma), meaning hidden colour. It is now used to describe a specific subset of blue light receptors, a family of flavoproteins that regulate germination, elongation, photoperiodism, and other responses in higher plants. Blue light also mediates phototropism, but this response is now known to have its own set of photoreceptors, the phototropins.

Cryptochromes are highly conserved molecules (evolutionary very old) derived from photolyase, a bacterial enzyme activated by light and participating in DNA damage repair. In eukaryotes the chryptochromes lost their enzymatic activity. Cryptochromes possess two chromophores: pterin and flavin (a chemical relative of pterin). Pterin absorbs a photon, which causes it to emit energy; the latter is absorbed by flavin, which probably mediates the phosphorylation of a certain domain in cryptochrome. This triggers a signal transduction chain that affects gene regulation in the cell nucleus.

Studies in animals and plants suggest that Cryptochromes play a pivotal role in the generation and maintenance of circadian rhythms [1]. In corals they are part of the mechanism that triggers coordinated spawning for a few nights after a full moon in the spring [2]. Cytochromes are also involved in magnetic orientation of birds during migration [3] and essential for the ability of fruit flies to sense magnetic fields [4].

The genes coding for two Cryptochromes, CRY1 and CRY2, are found on in many species - including in humans on chromosomes 12 and 11.


References

  1. ^ Klarsfeld, Andre (2004). "Novel features of chryptochrome-mediated photoreception in the brain circadian clock of Drosphila". Journal of Neuroscience. 24 (6): 1468–1477. doi:doi:10.1523/JNEUROSCI.3661-03.2004. Retrieved 2008-09-24. {{cite journal}}: Check |doi= value (help); Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  2. ^ Levy, O. (2007-10-19). "Light-responsive cryptochromes from a simple multicellular animal, the coral acropora millepora" (abstract). Science. 318 (5849): 467–470. doi:10.1126/science.1145432. PMID 17947585. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)CS1 maint: date and year (link)
  3. ^ Heyers, Dominik (2007). "A visual pathway links brain structures active during magnetic compass orientation in migratory birds". PLos ONE. 2 (9): e937. doi:10.1371/journal.pone.0000937. Retrieved 2007-09-27. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)CS1 maint: unflagged free DOI (link)
  4. ^ Gegear, Robert J. (2008). "Cryptochrome mediates light-dependent magnetosensitivity in Drosophila". Nature. 454: 1014–1018. doi:10.1038/nature07183. Retrieved 2008-09-24. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)