期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1999
卷号：96
期号：22
页码：12311-12315
DOI：10.1073/pnas.96.22.12311
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Chromatin remodeling complexes such as the SWI/SNF complex make DNA accessible to transcription factors by disrupting nucleosomes. However, it is not known how such complexes are targeted to the promoter. For example, a SWI/SNF1-like chromatin remodeling complex erythroid Kruppel-like factor (EKLF) coactivator-remodeling complex 1 (E-RC1) disrupts the nucleosomes over the human {beta}-globin promoter in an EKLF-dependent manner. However, it is not known whether E-RC1 is targeted specifically to the {beta}-globin promoter or whether E-RC1 is randomly targeted, but its activity is evident only at the {beta}-globin promoter. Because E-RC1 cannot remodel chromatin over the {beta}-globin promoter without EKLF in vitro, it has been proposed that SWI/SNF1-like complexes such as E-RC1 are targeted specifically to the promoter by selectively interacting with promoter-associated transcription factors such as EKLF. In this report, we test this hypothesis in the cellular context by using the ProteIN POsition Identification with Nuclease Tail (PIN*POINT) assay. We find that the Brahma-related gene (BRG) 1 and BRG1-associated factor (BAF) 170 subunits of E-RC1 are both recruited near the transcription initiation site of the {beta}-globin promoter. On transiently transfected templates, both the locus control region and the EKLF-binding site are important for their recruitment to the {beta}-globin promoter in mouse erythroleukemia cells. When the {beta}-globin promoter was linked to the cytomegalovirus enhancer, the E-RC1 complex was not recruited, suggesting that recruitment of the E-RC1 complex is not a general property of enhancers.
