Construction of Plasmids

The full-length BBX30, BBX30^D46A, BBX31, or BBX31^D45A open reading frame were cloned into the pDONR-223 vector (Invitrogen) and introduced into the plant binary vector pEarley Gateway 104 (Earley et al., 2006) under the 35S promoter using Gateway LR Clonase enzyme mix (Invitrogen). pEarley Gateway-YFP-BBX30, pEarley Gateway-YFP-BBX30^D46A, pEarley Gateway-YFP-BBX31, and Gateway-YFP- BBX31^D45A constructs were generated.

One-thousand-seven-hundred-eighty-nine-base-pair BBX30 and 1869-bp BBX31 promoters upstream of ATG were amplified by PCR with the respective pairs of primers and then cloned into the KpnI/XhoI sites of the pLacZ-2u vector (Lin et al., 2007). pET28a-HY5-His (Xu et al., 2016) and pB42AD-HY5 (Lin et al., 2018) constructs were described previously. The primers used for plasmids construction were listed in Supplemental Table S1.