Figure 1.

The expression pattern of MdMYB308L in response to cold stress (4°C treatment). (a) MdMYB308L gene expression detected by qRT‐PCR analysis. The value for 0 h was set to 1. (b) GUS staining and relative GUS activity analysis of the MdMYB308L promoter expression construct Pro_MdMYB308L::GUS in transgenic apple calli. Control: GUS staining and activity analysis at 9 h at 24°C. Cold treatment: GUS staining and activity analysis at 9 h under cold stress. (c) Degradation of the MdMYB308L‐GST fusion protein under cold stress. Total proteins extracted from wild‐type apple calli with or without 4°C treatments and the inclusion of 100 μm MG132 were incubated with the purified MdMYB308L‐GST fusion protein. The samples were collected at the indicated time. Control: 24°C; cold treatment: 4°C. ACTIN was used as internal reference. The relative intensity ratio between the GST and the ACTIN was shown. Each experiment was performed in three replicates. Error bars donate standard deviation. Significant differences were detected by t‐test (**P < 0.01).