Chromatin Immunoprecipitation (ChIP) is a tool that allowed us to determine the location of DNA binding sites on the genome for a given protein of interest. In some cases, it is usually more of a qualitative than a quantitative approach. ChIP also aims to determine the specific location in the genome that various histone modifications are associated with, indicating the target of the histone modifiers.
Creative Diagnostics can serve both standard ChIP assay and modified ChIP procedure to meet your research demands. Besides, we provide full line of downstream analysis for most methods, including PCR/qPCR-based assays, amplification, cloning, sequencing, library preparation and microarray analysis.
(1) N-ChIP: Native chromatin is used as the substrate, which means that proteins are not cross-linked to the DNA. Fragmentation of the chromatin is achieved by micrococcal nuclease digestion, resulting in a nucleosome based resolution. N-ChIP is restricted to proteins that are very tightly associated with chromatin, typically limiting this type of ChIP to histones and their modifications.
(2) X-ChIP: Cross-linking is typically achieved using formaldehyde and chromatin is fragmented by sonication, creating random fragments. As the proteins are cross-linked to the DNA a broad range of chromatin associated factors can be analyzed using this technique.
(3) Biotinylation-ChIP: This modified ChIP procedure is to solve the problem that the cross-linking is never complete. The system is based on co-expression of the target protein fused to a short biotin acceptor domain together with the biotinylating enzyme BirA from Escherichia coli. The superior strength of the biotin–avidin interaction allows one to employ more stringent washing conditions in the ChIP protocol, resulting in a better signal/noise ratio.
Creative Diagnostics offers its vast expertise in ChIP to many clients in the pharmaceutical, medical device and biotech industries. We are eager to learn of our customers' specific ChIP requirement and to facilitate their research and product development.
Please feel free to contact us if you have any questions regarding our service.