title: Localizing transcription factors on chromatin by immunofluorescence.
abstract: This article contains a detailed protocol for localizing transcription factors on Drosophila melanogaster polytene chromosomes by immunofluorescence. The large polytene chromosomes from third-instar larval salivary gland cells allow mapping of chromosome-associated proteins at high resolution. Thus, this method has been used to investigate how broadly transcription factors function and to identify and characterize cis-acting protein domains, trans-acting proteins, and trans-acting DNA elements that are necessary for chromosomal association of transcription factors. The ability to directly visualize transcription factors bound to chromosomes during a transcriptionally active stage of the cell cycle has greatly enhanced our understanding of how transcription factors function in vivo.
authors.affiliation: Cell Biology and Metabolism Branch, National Institute of Child Health and Human Development, National Institutes of Health, Building 18T, Room 101, Bethesda, MD 20892, USA.
authors.forename: Lori A
authors.initials: LA
authors.lastname: Pile
authors.forename: David A
authors.initials: DA
authors.lastname: Wassarman
mesh_terms: D000818:Animals; D002843:Chromatin / Q000378:metabolism*; D002875:Chromosomes; D004331:Drosophila melanogaster / Q000235:genetics*; D005455:Fluorescent Antibody Technique / Q000379:methods*; D008858:Microscopy, Phase-Contrast; D014157:Transcription Factors / Q000378:metabolism*
chemical_list: D002843:Chromatin; D014157:Transcription Factors