1.98 at midnight: 1 at dawn unitless
||African clawed frog Xenopus laevis
||Curran KL, LaRue S, Bronson B, Solis J, Trow A, Sarver N, Zhu H. Circadian genes are expressed during early development in Xenopus laevis. PLoS ONE. 2008 Jul 233(7)PubMed ID18716681
||Total RNA was extracted from eyes obtained from stage 31 and 40 embryos that represented different ZT times (0, 6, 12, and 18) using TRI reagent (Ambion). Eyes were dissected from embryos maintained in a 12L:12D cycle at different stages of development and different circadian times (ZT 0 (dawn), ZT6 (mid-day), ZT12 (dusk),and ZT18 (midnight)). The eyes were analyzed by qRT-PCR.
||This difference was found In stage 40 but not in stage 31 eyes