Dual roles of p300 in chromatin assembly and transcriptional activation in cooperation with nucleosome assembly protein 1 in vitro.
In a yeast two-hybrid screen to identify proteins that bind to the KIX domain of the coactivator p300, we obtained cDNAs encoding nucleosome assembly protein 1 (NAP-1), a 60-kDa histone H2A-H2B shuttling protein that promotes histone deposition. p300 associates preferentially with the H2A-H2B-bound form of NAP-1 rather than with the unbound form of NAP-1. Formation of NAP-1-p300 complexes was found to increase during S phase, suggesting a potential role for p300 in chromatin assembly. In micrococcal nuclease and supercoiling assays, addition of p300 promoted efficient chromatin assembly in vitro in conjunction with NAP-1 and ATP-utilizing chromatin assembly and remodeling factor; this effect was dependent in part on the intrinsic histone acetyltransferase activity of p300. Surprisingly, NAP-1 potently inhibited acetylation of core histones by p300, suggesting that efficient assembly requires acetylation of either NAP-1 or p300 itself. As p300 acted cooperatively with NAP-1 in stimulating transcription from a chromatin template in vitro, our results suggest a dual role of NAP-1-p300 complexes in promoting chromatin assembly and transcriptional activation.
Asahara
Hiroshi
H
Peptide Biology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037, USA.
Tartare-Deckert
Sophie
S
Nakagawa
Takeya
T
Ikehara
Tsuyoshi
T
Hirose
Fumiko
F
Hunter
Tony
T
Ito
Takashi
T
Montminy
Marc
M
D000818:Animals; D015153:Blotting, Western; D018797:Cell Cycle Proteins; D002467:Cell Nucleus / Q000378:metabolism; D002843:Chromatin / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004247:DNA / Q000378:metabolism; D004330:Drosophila; D029721:Drosophila Proteins; D004591:Electrophoresis, Polyacrylamide Gel; D006367:HeLa Cells; D006801:Humans; D009687:Nuclear Proteins / Q000378:metabolism*; D056490:Nucleosome Assembly Protein 1; D009707:Nucleosomes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D011506:Proteins / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D015534:Trans-Activators / Q000378:metabolism*; D014158:Transcription, Genetic; D015533:Transcriptional Activation; D020798:Two-Hybrid System Techniques; D015003:Yeasts
D018797:Cell Cycle Proteins; D002843:Chromatin; D029721:Drosophila Proteins; C533557:NAP1L1 protein, human; C533554:Nap1 protein, Drosophila; D009687:Nuclear Proteins; D056490:Nucleosome Assembly Protein 1; D009707:Nucleosomes; D011506:Proteins; D011994:Recombinant Proteins; D015534:Trans-Activators; D004247:DNA