Use of the β-Glucuronidase (GUS) Reporter System to Localize Promoter Activities of the Endogenous Plant Calpain DEFECTIVE KERNEL1 (DEK1)

The DEFECTIVE KERNEL1 (DEK1) gene encodes the unique plant calpain protein, which is fundamental for cell specification, development, and growth of land plants. The β-glucuronidase (GUS) reporter gene system has been used to characterize and localize gene expression over several decades. When cloning a promoter upstream of the uidA/GUS reporter gene, you visualize when the promoter is activating expression by monitoring enzymatic activity of GUS, by detecting β-glucuronidase cleavage products. Here we describe a protocol for monitoring the DEK1 promoter activity in different tissues in Arabidopsis by GUS staining.