title: The WSTF-ISWI chromatin remodeling complex transiently associates with the human inactive X chromosome during late S-phase prior to BRCA1 and γ-H2AX.
abstract: Replicating the genome prior to each somatic cell division not only requires precise duplication of the genetic information, but also accurately reestablishing the epigenetic signatures that instruct how the genetic material is to be interpreted in the daughter cells. The mammalian inactive X chromosome (Xi), which is faithfully inherited in a silent state in each daughter cell, provides an excellent model of epigenetic regulation. While much is known about the early stages of X chromosome inactivation, much less is understood with regards to retaining the Xi chromatin through somatic cell division. Here we report that the WSTF-ISWI chromatin remodeling complex (WICH) associates with the Xi during late S-phase as the Xi DNA is replicated. Elevated levels of WICH at the Xi is restricted to late S-phase and appears before BRCA1 and γ-H2A.X. The sequential appearance of WICH and BRCA1/γ-H2A.X implicate each as performing important but distinct roles in the maturation and maintenance of heterochromatin at the Xi.
authors.affiliation: Department of Biological Science, Florida State University, Tallahassee, Florida, United States of America.
authors.forename: Ashley E
authors.initials: AE
authors.lastname: Culver-Cochran
authors.forename: Brian P
authors.initials: BP
authors.lastname: Chadwick
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D019313:BRCA1 Protein / Q000378:metabolism; D001973:Bromodeoxyuridine; D042002:Chromatin Assembly and Disassembly / Q000235:genetics / Q000502:physiology*; D041321:Chromosomes, Human, X / Q000235:genetics / Q000378:metabolism*; D004261:DNA Replication / Q000502:physiology*; D044127:Epigenesis, Genetic / Q000235:genetics / Q000502:physiology*; D005260:Female; D005455:Fluorescent Antibody Technique; D006657:Histones / Q000378:metabolism; D006801:Humans; D007091:Image Processing, Computer-Assisted; D017404:In Situ Hybridization, Fluorescence; D016196:S Phase / Q000502:physiology*; D014157:Transcription Factors / Q000378:metabolism; D049951:X Chromosome Inactivation / Q000235:genetics*; D000092468:Bromodomain Containing Proteins
chemical_list: D000251:Adenosine Triphosphatases; D019313:BRCA1 Protein; D001973:Bromodeoxyuridine; D006657:Histones; D014157:Transcription Factors; C116750:BAZ1B protein, human; D000092468:Bromodomain Containing Proteins; C468783:H2AX protein, human; C086468:ISWI protein