Plant Proteins, Peptides and Antigens Protocol Links
A Novel Fluorescent pH Probe for Expression in Plants The pH is an important parameter controlling many metabolic and signalling pathways in living cells. Recombinant fluorescent pH indicators (pHluorins) have come into vogue for monitoring cellular pH. They are derived from the most popular Aequorea victoria GFP (Av-GFP). Here, we present a novel fluorescent pH reporter protein from the orange seapen Ptilosarcus gurneyi (Pt-GFP) and compare its properties with pHluorins for expression and use in plants.
Blue-Native PAGE in Plants: A Tool in Analysis of Protein-Protein Interactions BN-PAGE has become the method of choice for the investigation of the respiratory protein complexes of the electron transfer chains of a range of organisms. It allows the separation in two dimensions of extremely hydrophobic protein sets for analysis and also provides information on their native interactions. In this review we discuss the capabilities of BN-PAGE in proteomics and the wider investigation of protein:protein interactions with a focus on its use and potential in plant science.
Fractionation of Maize Embryo Proteins for 2-D Gel Electrophoresis Using Multicompartment Electrolyz Protocol describes a method for performing isoelectric fractionation of a maize embryo sample using a multicompartment electrolyzer(MCE). This prefractionation of proteins having pIs within a certain pH interval is essential for allowing high loads of protein to be resolved on narrow and ultra-narrow immobilized pH gradients used in 2D electrophoresis. The isoelectric membranes in the MCE act like isoelectric traps capturing all the protein species having pIs encompassing the pI value of each...
Quantitative GUS Activity Assay in Intact Plant Tissue Protocol 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...
Quantitative GUS Activity Assay of Plant Extracts Using excitation at 365 nm and measuring emission at 455 nm, the amount of 4-MU produced can be quantified. Under these conditions, background fluorescence from the substrate is negligible, especially if the appropriate filter is selected.
Subcellular Localization of GUS- and GFP-Tagged Proteins in Onion Epidermal Cells GUS is used as a tag to address nuclear localization whereas GFP is more versatile. GFP is detectable directly in living cells, GUS is only detected indirectly by staining of fixed tissue which may lead to artifacts or may obscure problems with protein solubility. In this protocol, protein localization is routinely assayed after particle-mediated transient transformation of onion epidermal cells. With this method it can be determined rapidly whether a given fusion protein is active and....
