The cell biology of a novel chromosomal RNA: chromosome painting by XIST/Xist RNA initiates a remodeling cascade.
X chromosome inactivation begins when a novel chromosomal RNA (cRNA) from the imprinted mouse Xist or human XIST locus coats or "paints" one X chromosome in cis and initiates a cascade of chromosome remodeling events. Molecular cytological studies have proven invaluable for understanding the distinctive cellular behavior of this singular RNA involved in chromosome structure and regulation. While the detailed mechanism of XIST/Xist (X-inactivation Specific Transcript) RNA function remains largely unknown, recent advances provide new insights into the complex cellular factors which impact the RNA's localization to the chromosome, as well as the early events of chromosome remodeling that follow painting by Xist RNA. Because chromatin changes can be directly visualized on a silenced chromosome, X chromosome inactivation provides an advantageous model to investigate genome-wide heterochromatin formation and maintenance, with wide-ranging implications for normal cells and disease.
Hall
Lisa L
LL
Department of Cell Biology, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, MA 01655, USA. lisa.hall@umassmed.edu
Lawrence
Jeanne B
JB
D000818:Animals; D019313:BRCA1 Protein / Q000235:genetics / Q000378:metabolism; D042002:Chromatin Assembly and Disassembly; D020223:Chromosome Painting; D004303:Dosage Compensation, Genetic; D018392:Genomic Imprinting; D006801:Humans; D051379:Mice; D062085:RNA, Long Noncoding; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D015138:RNA, Nuclear / Q000235:genetics* / Q000378:metabolism; D022661:RNA, Untranslated / Q000235:genetics* / Q000378:metabolism; D014960:X Chromosome / Q000235:genetics* / Q000378:metabolism
D019313:BRCA1 Protein; D062085:RNA, Long Noncoding; D012333:RNA, Messenger; D015138:RNA, Nuclear; D022661:RNA, Untranslated; C077885:XIST non-coding RNA