Cryptochrome (CRY) gene family encodes photoreceptors mediating developmental responses to blue light throughout the life
of plants. We report here the characterization of
CRY gene family in hexaploid wheat. Degenerate PCR amplification of the regions encoding the conserved flavin-binding domain
of CRY proteins yielded seven bands, resulting from amplification of
CRY1a,
CRY1b and
CRY2 homologous genes. Assignment of individual amplicons to subgenomes was accomplished by comparing their sequence compositions
with those from the ancestor species of wheat. ESTs coding for CRY-DASH like proteins were identified in wheat EST database
in GenBank. Southern blot showed that
TaCRY1a,
TaCRY1b and
TaCRY2 are single copy genes. We mapped
TaCRY1a and
TaCRY2 to chromosomes of homoeologous group 6,
TaCRY1b to group 2, and
TaCRY-DASH to group 7. Phylogenetic analysis showed that
CRY subfamily diversification occurred before the divergence of monocots and dicots. The regulatory and functional changes of
CRY members within subfamily are discussed.
Keywords Cryptochrome - Gene family - Phylogeny - Wheat