title: A HaloTag-based small molecule microarray screening methodology with increased sensitivity and multiplex capabilities.
abstract: Small Molecule Microarrays (SMMs) represent a general platform for screening small molecule-protein interactions independent of functional inhibition of target proteins. In an effort to increase the scope and utility of SMMs, we have modified the SMM screening methodology to increase assay sensitivity and facilitate multiplex screening. Fusing target proteins to the HaloTag protein allows us to covalently prelabel fusion proteins with fluorophores, leading to increased assay sensitivity and an ability to conduct multiplex screens. We use the interaction between FKBP12 and two ligands, rapamycin and ARIAD's "bump" ligand, to show that the HaloTag-based SMM screening methodology significantly increases assay sensitivity. Additionally, using wild type FKBP12 and the FKBP12 F36V mutant, we show that prelabeling various protein isoforms with different fluorophores allows us to conduct multiplex screens and identify ligands to a specific isoform. Finally, we show this multiplex screening technique is capable of identifying ligands selective for a specific PTP1B isoform using a 20,000 compound screening deck.
authors.affiliation: Department of Molecular Cellular and Developmental Biology, Yale University, 219 Prospect Street, New Haven, CT 06511, USA.
authors.forename: Devin J
authors.initials: DJ
authors.lastname: Noblin
authors.forename: Charlotte M
authors.initials: CM
authors.lastname: Page
authors.forename: Hyun Seop
authors.initials: HS
authors.lastname: Tae
authors.forename: Peter C
authors.initials: PC
authors.lastname: Gareiss
authors.forename: John S
authors.initials: JS
authors.lastname: Schneekloth
authors.forename: Craig M
authors.initials: CM
authors.lastname: Crews
mesh_terms: D001483:Base Sequence; D017931:DNA Primers; D040081:Protein Array Analysis; D054852:Small Molecule Libraries; D022061:Tacrolimus Binding Protein 1A / Q000737:chemistry*
chemical_list: D017931:DNA Primers; D054852:Small Molecule Libraries; D022061:Tacrolimus Binding Protein 1A