The assay for ß-galactosidase relies on the ability of the enzyme to catalyze the hydrolysis of ONPG (o-nitrophenyl-ß-D- galactopyranoside) to free o-nitrophenol, which absorbs light at 420 nm. In this protocol, extracts of cells transfected with a ß-galactosidase reporter plasmid are incubated with ONPG. - [Read Assay for ß-galactosidase in Extracts of Mammalian Cells]
The activity of ß-glucuronidase (GUS) can be accurately determined in intact plant tissue using 4-methylumbelliferyl ß-D-glucuronide (4-MUG) as a substrate. Upon hydrolysis by GUS, the fluorochrome 4-methyl umbelliferone (4-MU) is produced. This method is based on the permeability of both 4-MUG and 4-MU through plant tissue. It consists of incubation of the tissue with the reagent and quantification of the fluorescence emitted by 4-MU in the solution. GUS activity in each sample can be... - [Read Quantitative GUS Activity Assay in Intact Plant Tissue Protocol]
Run-on transcription monitors the regulation of transcription in isolated nuclei. Protocol includes: Preparation of Nuclei, Run-On Transcription Reaction, Alkaline Hydrolysis of Run-Off Transcripts, Preparation of Filters and Hybridization. Solutions included: DNase Solution, Hybridization Mix, Denhardt Solution (100X) etc. - [Read Run- On Transcription Protocol]