Geneva: Techniques for mapping DNA bound proteins

Licensing opportunity

Ulrich Laemmli at the University of Geneva, in Switzerland, is looking to license his proprietary assay system, which maps transcription factors found along highly condensed DNA strands in chromosomes. The technique relies on using micrococcal nucleases that cleave the DNA double strands at specific sites, which can subsequently be mapped.

The chromatin endogenous cleavage (ChEC) and chromatin immunocleavage (ChIC) mapping techniques developed by Laemmli yield low-background and high-resolution protein mapping, in contrast to conventional chromosomal protein mapping techniques such as chromatin immunoprecipitation (ChIP). Researchers say the techniques are highly specific and can be applied to structural or soluble proteins found in fixed or native cells.

ChEC is an in vivo technique, which relies on the tethering of an inactivated micrococcal nuclease to the gene of interest using a fusion protein. The ChIC technique consists in binding the microsomal nuclease to target genes in vitro using specific antibodies. In both cases calcium ions induce the micrococcal nucleases to cleave the DNA double strands at specific sites, which are subsequently mapped with high precision of up to base pair resolution.