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A Facile Protocol to Generate Site-Specifically Acetylated Proteins in Escherichia Coli
Published on: December 9, 2017
Expanded lysine acetylation specificity of Gcn5 in native complexes
P A Grant1, A Eberharter, S John
1Howard Hughes Medical Institute, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802-4500, USA.
The Journal of Biological Chemistry
|February 20, 1999
Summary
The yeast protein Gcn5, a histone acetyltransferase, gains broader nucleosomal histone modification capabilities when part of the Ada and SAGA complexes. These complexes influence Gcn5
Area of Science:
- Molecular Biology
- Biochemistry
- Yeast Genetics
Background:
- Gcn5 is a histone acetyltransferase crucial for transcriptional regulation in yeast.
- Gcn5's activity on nucleosomal histones is lower than on free histones, primarily targeting H3 lysine 14.
- Multisubunit complexes enhance Gcn5's nucleosomal histone acetyltransferase activity.
Purpose of the Study:
- To investigate how association with protein complexes affects Gcn5's histone acetyltransferase activity and substrate specificity.
- To determine if the Ada and SAGA complexes confer distinct acetylation patterns mediated by Gcn5.
Main Methods:
- Analysis of native yeast complexes (Ada and SAGA).
- Characterization of Gcn5's acetylation activity within these complexes.
- Comparison of histone H3 acetylation patterns in the presence of different complexes.
Main Results:
- Association of Gcn5 with Ada and SAGA complexes enables acetylation of additional lysines on histone H3.
- The Ada and SAGA complexes exhibit both shared and unique patterns of histone H3 acetylation.
- Specific subunits within the complexes dictate Gcn5's site specificity.
Conclusions:
- Gcn5's catalytic activity and substrate specificity are significantly modulated by its assembly into multisubunit complexes like Ada and SAGA.
- The composition of these complexes determines the precise pattern of histone acetylation, highlighting a regulatory mechanism in gene transcription.
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