B6.129P2-Cry2^tm1Asn/J

Stock number: 016185
Research areas: Neurobiology Research

Description

These knockout Cry2 (cryptochrome 2 (photolyase-like)) mice demonstrate a circadian period about 1 hour longer than normal.

Detailed description

These targeted mutant Cry2 (cryptochrome 2 (photolyase-like); blue-light photoreceptor) mice have a lower sensitivity to acute light induction of Per1 (period homolog 1 (Drosophila)) in the suprachiasmic nucleus (SCN), but exhibit normal circadian oscillations of Per1 and Cry1 (cryptochrome 1 (photolyase-like)) mRNA in the SCN. The mutant has an intrinsic circadian period about 1 hour longer than normal and exhibits high-amplitude phase shifts in response to light pulses administered at circadian time 17. Homozygotes are viable and born at predicted Mendelian ratios. Analysis of homozygotes by Northern and in situ hybridization revealed a complete lack of mRNA.

Development

A 1.1 kb segment that encodes the flavine adenine dinucleotide (FAD) binding domain was replaced by a neomycin resistance cassette. 129P2/OlaHsd-derived E14TG2a embryonic stem (ES) cells were used to create the mutation. This strain was backcrossed to C57BL/6J for more than 13 generations by the donating laboratory.

Allele

Symbol: Cry2^tm1Asn
Name: targeted mutation 1, Aziz Sancar
MGI accession ID: MGI:2181212
Generation method: Targeted
Attributes: Null/Knockout
Marker symbol: Cry2
Marker name: cryptochrome 2 (photolyase-like)
Chromosome: 2
Strain of origin: 129P2/OlaHsd
Molecular note: A neomycin selection cassette replaced a 1.1-kb region encoding the FAD-binding domain. Northern blot analysis and in situ hybridization showed a lack of transcript and protein in homozygous mutant mice.