title: Label free analysis of transcription factors using microcantilever arrays.
abstract: We report the measurement of protein interaction with double-stranded DNA oligonucleotides using cantilever microarray technology. We investigated two different DNA-binding proteins, the transcription factors SP1 and NF-kappaB, using cantilever arrays as they allow label-free measurement of different biomolecular interactions in parallel. Double-stranded DNA oligonucleotides containing a specific binding site for a transcription factor were sensitized on gold-coated cantilevers. The binding of the transcription factor creates a surface stress, resulting in a bending of the cantilevers. Both transcription factors could be detected independently at concentrations of 80-100 nM. A concentration dependence of the bending signal was measured using concentrations from 100 to 400 nM of NF-kappaB. The experiments show that the recognition sequence of one transcription factor can serve as a reference for the other, highlighting the sequence specificity of transcription factor binding.
authors.affiliation: Institute of Physics, University of Basel, Switzerland. Francois.Huber@unibas.ch
authors.forename: François
authors.initials: F
authors.lastname: Huber
authors.forename: Martin
authors.initials: M
authors.lastname: Hegner
authors.forename: Christoph
authors.initials: C
authors.lastname: Gerber
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Güntherodt
authors.forename: Hans Peter
authors.initials: HP
authors.lastname: Lang
mesh_terms: D004247:DNA / Q000032:analysis* / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000032:analysis* / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D040081:Protein Array Analysis / Q000295:instrumentation* / Q000379:methods; D012031:Refractometry / Q000295:instrumentation* / Q000379:methods; D013194:Staining and Labeling; D014157:Transcription Factors / Q000032:analysis* / Q000737:chemistry
chemical_list: D004268:DNA-Binding Proteins; D014157:Transcription Factors; D004247:DNA