Key points are not available for this paper at this time.
Yongmin Hou, Albrecht G. von Arnim, Xing-Wang Deng, A New Class of Arabidopsis Constitutive Photomorphogenic Genes Involved in Regulating Cotyledon Development, The Plant Cell, Vol. 5, No. 3 (Mar., 1993), pp. 329-339
Hou et al. (1993) studied this question.