Figure 2.

Circadian changes in binding activity of Chlamy 1 and of Chlamy 2 and 3 (with reduced amplitude in the last two cases). (A) Autoradiograms of mobility-shift assays using the ³²P-labeled BglI transcript in the presence of poly(G). One lane (RNA BglI) always demonstrates the mobility of the transcript alone. Chlamydomonas crude extracts were prepared from cells grown under LD 12/12 and harvested every 4 hr at the indicated times. (B) Cells were grown up under LD 12/12 and then put under constant dim light (LL: stippled) and harvested at the indicated times. Times are given in hours after lights were switched on. Subjective day phase, less-dense stippling; subjective night phase, dense stippling.