title: Mechanism of hsp70i gene bookmarking.
abstract: In contrast to most genomic DNA in mitotic cells, the promoter regions of some genes, such as the stress-inducible hsp70i gene that codes for a heat shock protein, remain uncompacted, a phenomenon called bookmarking. Here we show that hsp70i bookmarking is mediated by a transcription factor called HSF2, which binds this promoter in mitotic cells, recruits protein phosphatase 2A, and interacts with the CAP-G subunit of the condensin enzyme to promote efficient dephosphorylation and inactivation of condensin complexes in the vicinity, thereby preventing compaction at this site. Blocking HSF2-mediated bookmarking by HSF2 RNA interference decreases hsp70i induction and survival of stressed cells in the G1 phase, which demonstrates the biological importance of gene bookmarking.
authors.affiliation: Department of Molecular and Cellular Biochemistry, Chandler Medical Center, University of Kentucky, Lexington, KY 40536, USA.
authors.forename: Hongyan
authors.initials: H
authors.lastname: Xing
authors.forename: Donald C
authors.initials: DC
authors.lastname: Wilkerson
authors.forename: Christopher N
authors.initials: CN
authors.lastname: Mayhew
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Lubert
authors.forename: Hollie S
authors.initials: HS
authors.lastname: Skaggs
authors.forename: Michael L
authors.initials: ML
authors.lastname: Goodson
authors.forename: Yiling
authors.initials: Y
authors.lastname: Hong
authors.forename: Ok-Kyong
authors.initials: OK
authors.lastname: Park-Sarge
authors.forename: Kevin D
authors.initials: KD
authors.lastname: Sarge
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D045744:Cell Line, Tumor; D047369:Chromatin Immunoprecipitation; D004268:DNA-Binding Proteins / Q000378:metabolism; D005786:Gene Expression Regulation; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics*; D006367:HeLa Cells; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006358:Hot Temperature; D006801:Humans; D047468:Immunoprecipitation; D007399:Interphase; D008938:Mitosis; D046912:Multiprotein Complexes; D010749:Phosphoprotein Phosphatases / Q000378:metabolism; D010766:Phosphorylation; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D054648:Protein Phosphatase 2; D021122:Protein Subunits / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000494:pharmacology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D020798:Two-Hybrid System Techniques
chemical_list: D004268:DNA-Binding Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D046912:Multiprotein Complexes; D021122:Protein Subunits; D034741:RNA, Small Interfering; D014157:Transcription Factors; C108312:condensin complexes; C070389:HSF2 protein, human; D010749:Phosphoprotein Phosphatases; D054648:Protein Phosphatase 2; D000251:Adenosine Triphosphatases