White collar complex

The 54 kDa wc-2 protein (WC-2) contains a nuclear-targeting domain and a PAS domain. Both the mRNA and protein are constitutively expressed, and the polypeptide appears to undergo no circadian phase-dependent modifications, though it is phosphorylated in response to light.The WC-2 PAS domain dimerizes with itself and with WC-1 via its PAS domain, forming hetero- and homodimers in vitro and in vivo. > Together, WC-1 and WC-2 form the white collar complex (WCC) in which both proteins appear in a 1 1 stoichiometry. This differs from the cellular concentrations of the two... 

Talora, C., Franchi, L., Linden, H., Ballario, R, and Macino, G., Role of a white collar-1-white collar-2 complex in blue-light signal transduction, EMBO J., 18, 4961, 1999. 

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