Part:BBa_K243028

pMA FOS-Split Linker-Fok_a

Activator protein-1 (AP-1) is a crucial transcription factor implicated in numerous cancers and binds DNA as a dimer. Two classes of core DNA sequences, the sequences TRE (TGACTCA) and CRE (TGACGTCA), can be recognized by the AP-1. Nine homologues of the AP-1 leucine zipper region have been characterized. All of them are able to form heterodimers, some also form homodimers. One of them is the so called c-Fos. Via leucin zipper they interact among each other and with their bipartite domain they bind DNA. (Abate et al., Mol Cell Biol. 1991 July).

Heterodimeric Fos complex (http://www.rcsb.org/pdb/explore/images.do?structureId=1FOS)

Usage and Biology

To avoid the labeling of oligos we tried an alternative way of binding of the heterodimeric Fok to the DNA, by using the DNA binding domain of the protein as adapter between the Fok construct and the DNA. For our needs, we chose the natural bZIP sequence of Fos and Jun as well as the library-selected FosW sequence.

Split Linker-Fok_a can be fused with Fos. The mixture of this construct with an other hybrid protein GST-FosW-His (simultanously expressed) allows the dimerization of Fos and therefore its binding at their target sequence TRE (TGACTCA) or CRE (TGACGTCA)