CLIP-Cell™ 505 is a green fluorescent substrate that can be used to label CLIP-tag™ fusion proteins inside living cells, on cell surfaces or in vitro. This cell-permeable substrate (BC-505) is based on the Dyomics dye DY-505 and is suitable for standard fluorescein filter sets. It has an excitation maximum at 504 nm and emission maximum at 532 nm. This package includes 50 nmol of CLIP-Cell 505 substrate, sufficient to make 10 ml of a 5 µM CLIP-tag fusion protein labeling solution.
The CLIP-tag protein labeling system enables the specific, covalent attachment of virtually any molecule to a protein of interest. CLIP-tag is a protein tag based on human O6-alkylguanine-DNAalkyltransferase (hAGT). CLIP-tag substrates are derivatives of benzylcytosine (BC). In the labeling reaction, the substituted benzyl group of the substrate is covalently attached to the reactive cysteine of CLIP-tag forming a stable thioether bond. Although CLIP-tag is based on the same protein as SNAP-tag®, the benzylcytosine substrates form a separate class of substrates, different from the benzylguanine substrates recognized by SNAP-tag. CLIP-tag and SNAP-tag can be used for orthogonal and complementary labeling of two proteins simultaneously in the same cells.
There are two steps to using this system: subcloning and expression of the protein of interest as a CLIP-tag fusion with the CLIP-tag fusion proteins is described in the documentation supplied with CLIP-tag plasmids. The labeling of the fusion proteins is described in this document.
Materials Required but not Supplied
• Cells expressing CLIP-tag fusion proteins
• Tissue culture materials and media
• Transfection reagents
• Fluorescence microscope with suitable filter set